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General Category => Amstrad CPC hardware => Topic started by: MacDeath on 13:52, 23 October 09

Title: ACID chip inside
Post by: MacDeath on 13:52, 23 October 09
Salut à tous....

Well, there are some discussion on many Forums about the ACID chip.

As you know, this is the chip no Amstrad Plus work whithout...
and the most unknown too.

Spanish Amstraders are actually trying to analyse it properly.

French are talking about it, mostly trying to decipher the spanish talks....as we speack spanish like British Cows too. ;)

It would be great to assemble all the stuff from all over the CPC world community, links, etc...on the matter.



Also, It seems there's an Urban Legend about a company with 500 ACID chips to sell.

(http://img291.imageshack.us/img291/5103/500acid.jpg)
link to said list :
http://www.n-tronics.com/english/stock/available_stock.php

I sent a mail to them to get more information (price, is it really ACID chip...)

Is it true ? or a CPC mythos ? (seems to be true, lol...merci Fano.)


As you also know, GX/Plus cartridges can be quite expensive on internet !
A  "professionnal" MultiEEprom cartridge production would be great.

But we must check all those information first.


Wiki Links :

http://cpcwiki.eu/index.php/CPC_GX4000-Multi_EPROM_Cartridge
http://cpcwiki.eu/index.php/Amstrad_Cartridge_Identification_Device

Other links :

Spanish :
http://amstradcpc.mforos.com/305097/7723493-que-hace-exactamente-el-chip-acid-de-los-cartuchos/

French :
http://www.vieuzordiland.fr/index.php?option=com_content&task=view&id=23&Itemid=34
http://www.vieuzordiland.fr/index.php?option=com_content&task=view&id=60&Itemid=34

http://cpcrulez.fr/forum/viewtopic.php?f=5&t=3904
(our pathetic try to understand spanish, lol)



Please, if you have linkto discusssion on the ACID, tell what langage it is too.
I will edit this first post to add them all.then let's Babelfish do the job.

Also, this thread is open to discussion on the ACID interaction with ASIC.


As some crackers say : no protection hasn't been cracked yet...

Well, the ACID is no soft protection (but hardware one...) yet it is still uncracked !


Title: Re: ACID chip inside
Post by: fano on 16:13, 23 October 09
Quote from: MacDeath on 13:52, 23 October 09
Also, It seems there's an Urban Legend about a company with 500 ACID chips to sell.

Is it true ? or a CPC mythos ?
As i replied @cpcrulez , there is a site that pretends to own 500 ACID in stock :http://www.n-tronics.com/english/stock/available_stock.php (http://www.n-tronics.com/english/stock/available_stock.php) (stock list 4)
No clues about pricing, i remember TFM/FS posted something about this, maybe he contacted them.
Title: Re: ACID chip inside
Post by: Gryzor on 11:39, 26 October 09
Did the company actually write back anyway? That'd be a great boon...
Title: Re: ACID chip inside
Post by: fano on 12:18, 26 October 09
(http://img199.imageshack.us/img199/7497/asicprice.jpg)

If someone if interested , there is the reply when i asked for minimal order :

Thank you.

Please order what you need.

We would be grateful for an early reply.

Kind regards
Title: Re: ACID chip inside
Post by: Gryzor on 17:19, 08 November 09
Um.... ok, so do we order?
Title: Re: ACID chip inside
Post by: fano on 07:22, 09 November 09
waiting to success in prototyping a 512K cartrige  ;)
Title: Re: ACID chip inside
Post by: MacDeath on 18:40, 09 November 09
And if so, a 512Ko Multi E(E)PROM serie would be so fine...
Title: Re: ACID chip inside
Post by: khisanth on 20:17, 22 November 09
This kind of project would be great to use Google Wave. Big collaboration, sharing documents, video, audio, emails, chat etc
Title: Re: ACID chip inside
Post by: MacDeath on 07:26, 23 November 09
Too bad those spanish amstradist don't come here so often an don't allways speack english well (like french cows ?)...

Please spanish friends...
Share a bit more !
Title: Re: ACID chip inside
Post by: arnoldemu on 17:10, 23 November 09
Quote from: MacDeath on 07:26, 23 November 09
Too bad those spanish amstradist don't come here so often an don't allways speack english well (like french cows ?)...

Please spanish friends...
Share a bit more !
I am talking with Steve at this time.
Don't forget that both of us are busy.
Title: Re: ACID chip inside
Post by: fano on 18:39, 23 November 09
Quote from: arnoldemu on 17:10, 23 November 09
I am talking with Steve at this time.
Don't forget that both of us are busy.
Take your time , we are waiting since 20 years so we'll wait a bit more ;)
Title: Re: ACID chip inside
Post by: pepax on 17:59, 27 November 09
Quote from: fano on 07:22, 09 November 09
waiting to success in prototyping a 512K cartrige  ;)
How about buying just a few and testing them in an original cartridge? :)
Title: Re: ACID chip inside
Post by: fano on 18:21, 27 November 09
I am waiting to own an EPROM burner to make tests.
Just a bit of code that testes all ROM pages to see how act LKs.

Problem is postage fee are high so this a is a bit expensive to purchave a little quantity :s
Title: Re: ACID chip inside
Post by: Gryzor on 08:04, 28 November 09
How much is it? Maybe we could chip in...
Title: Re: ACID chip inside
Post by: fano on 12:41, 29 November 09
That would be interesting, they send them via UPS and as i saw , the minimal cost is around 100Euros.
Title: Re: ACID chip inside
Post by: pepax on 21:08, 30 November 09
Quote from: fano on 12:41, 29 November 09
That would be interesting, they send them via UPS and as i saw , the minimal cost is around 100Euros.
So someone has to buy at least 25pcs? Too bad...
I'd take 2.  :)
Title: Re: ACID chip inside
Post by: pepax on 16:23, 02 December 09
You can also buy the chips from Gustronic for Euro 6,20 apiece, minimum order 50 pieces. Happy shopping!  ;D
Title: Re: ACID chip inside
Post by: Gryzor on 18:57, 02 December 09
I'd get two or three myself... let's get it to 50, shall we? :)
Title: Re: ACID chip inside
Post by: pepax on 23:15, 02 December 09
I'd vote for the cheaper ones......  :D
Title: Re: ACID chip inside
Post by: redbox on 22:24, 06 December 09
I'd vote for anything that lets me play Pang on my 6128 Plus.

That's the game that makes the Crummadore kids go very quiet  8)
Title: Re: ACID chip inside
Post by: TFM on 19:53, 14 December 09
Hola y Buenos dias,

Today I send a mail to that company (n-tronics) to tell me the price for 25, 50 or 100 pieces of the IL03P1003 Amstard IC.

Depending on the price I will take between 25-100 for FutureSoft projects.

However it shouldn't be a problem to send some of them to interrested people in europe.

Another question is ... is there anybody who can create the boards for the Plus-Cartridges? The 512 KB version in particular.

Au revoir,
TFM de la FutureSoft
Title: Re: ACID chip inside
Post by: MacDeath on 01:28, 16 December 09

QuoteI'd vote for anything that lets me play Pang on my 6128 Plus.

That's the game that makes the Crummadore kids go very quiet  8)
Well, now it will be rick dangerous 128+...

any way, this would be so kool if we could produce multi-eeprom cartridges...
As the number of ACID chip seems quite limited...this would be the best method so we could all get one and fuck deeply speculators on Ebay...

Has any one tested to put a 512Ko or 256Ko Rom on a cartridge ?

What kind of software should we put inside this Rom to test it ?
I mean, if we want to test those cartridge, doing measurments is good, this alows to understand...

But a special testing programm would be nice indeed and maybe easier ?

So what kind of software would do it ?
Title: Re: ACID chip inside
Post by: redbox on 13:20, 16 December 09
Quote from: MacDeath
any way, this would be so kool if we could produce multi-eeprom cartridges...

This is what I would like to do, kind of like a ROMbox but as a cartridge (maybe with a switch to select the ROM in use?).

Quote from: MacDeath
Has any one tested to put a 512Ko or 256Ko Rom on a cartridge ?

The Pang ROM is 512kb amongst others and people have successfully burnt this to a ROM and used it (here (http://cpcrulez.free.fr/hardware_montage_DIP32_GX4000.htm) and here (http://www.vieuzordiland.fr/index.php?option=com_content&task=view&id=23&Itemid=34)).

I would like to make one of these (http://www.cpcwiki.eu/index.php/CPC_GX4000-Multi_EPROM_Cartridge) if I could buy a ASIC chip. The PCB is very simple and it would mean not destroying my 6128+ system cartridge.

Quote from: MacDeath
What kind of software should we put inside this Rom to test it ?
I mean, if we want to test those cartridge, doing measurments is good, this alows to understand...

The Arnold V Diagnostic Cartridge on the WinApe website (http://www.winape.net/downloads.jsp) could be a good place to start to see if the ASIC is working....?
Title: Re: ACID chip inside
Post by: fano on 13:44, 16 December 09
Quote from: redbox on 13:20, 16 December 09The Pang ROM is 512kb amongst others and people have successfully burnt this to a ROM and used it
Not really , you can check data redudancy of CPR file  to see it is in fact a 128K ROM.The LK switches seem to be used to invalidate the higher bits in ROM and to roll adressing.
Someone who owns Pang can confirm this fact when looking eprom type used for this game.

N-Tronic replied 4 Euros per chip without fee cost.
Title: Re: ACID chip inside
Post by: redbox on 16:11, 16 December 09
Quote from: fano on 13:44, 16 December 09
Not really , you can check data redudancy of CPR file  to see it is in fact a 128K ROM.

Does this mean it would be possible to put in onto a disk?

Quote from: fano on 13:44, 16 December 09
N-Tronic replied 4 Euros per chip without fee cost.

What is the 'fee cost' and how much is it?
Title: Re: ACID chip inside
Post by: fano on 18:36, 16 December 09
Quote from: redbox on 16:11, 16 December 09Does this mean it would be possible to put in onto a disk?
About CPR files, i was speaking about ROM dumps.You can put a 128K rom dump on a CPC disk but that will not be very usefull.


Quote from: redbox on 16:11, 16 December 09
What is the 'fee cost' and how much is it?
Sorry , i meant postage fee or delivery cost  :-[  i saw Ntronics uses UPS and the minimal cost to send something is about 100Euros.
Title: Re: ACID chip inside
Post by: redbox on 12:13, 17 December 09
Quote from: fano on 18:36, 16 December 09
Sorry , i meant postage fee or delivery cost  :-[  i saw Ntronics uses UPS and the minimal cost to send something is about 100Euros.

UPS Standard to deliver a 1kg package from Germany (Treuchtlingen, N-Tronics) to the UK is 30 Euros.

They also let you use Fedex, DHL, TNT etc which may be even cheaper and say if you prefer an other company, please email us your accountnumber, and the service you wish to use (http://www.n-tronics.com/english/contact/shipment.php).
Title: Re: ACID chip inside
Post by: fano on 11:49, 19 December 09
 :o

That's weird , i made a simulation for France (150 kms from Paris) and i got 100Euros !
I am going to look at this more.
Title: Re: ACID chip inside
Post by: MacDeath on 06:56, 05 January 10
Are there any news about the ACID deciphering project ?
Title: Re: ACID chip inside
Post by: nocash on 23:51, 09 January 10
> Spanish Amstraders are actually trying to analyse it properly.
> French are talking about it, mostly trying to decipher the spanish talks....
> Are there any news about the ACID deciphering project ?

Oh-oh, and english speaking people discuss about eventually buying a real ACID chip ;-) aren't that chips mass-produced and included in all game and system cartridges anyways?

If somebody should happen to want to donate a cartridge, and maybe even a gx4000, I am sure I could figure out how it works in 2-3 days - you can make jokes on me for the rest of my life if I can't :-)
Title: Re: ACID chip inside
Post by: fano on 00:22, 10 January 10
lol nice analyse  ;D

Why not ? where do you live ?

ACID is a question , LKs configuration is another.

I would like to know how LK0-6 alter memory addressing but i do not own needed stuff actually to do that (mainly eprom burner/eraser).So i have hypothesis about LKs but i can not check it for now.
Title: Re: ACID chip inside
Post by: MacDeath on 02:19, 10 January 10
Haha, nice try "nocash"...

But We all know that GX4000 are gettting high priced on Ebay thx to those stupid retro-game collectionners.
So are Plus cartridges...

You just don't want to pay the 50-75€uros to get those to complete your collection. :o
Title: Re: ACID chip inside
Post by: nocash on 02:36, 10 January 10
> Why not ? where do you live ?
Germany/Hamburg. Is that okay?

> I would like to know how LK0-6 alter memory addressing
That's more or less described / shown on photos, here:
  http://cpcwiki.eu/index.php/GX4000_cartridge
the only info that is missing there is a table or schematic that shows which signals connect to which jumpers, no big problem. Most or all of them don't seem to alter addressing at all, just deal with slightly different pin-outs.

For example, LK3 apparently connects 5V supply to Pin28 of 64K chips (with 28pins), on bigger chips (with 32pins), supply is on Pin32, and the above pin is instead used as address line (and must be connected with one of the other LK's).

And the ACID, meanwhile, I've began wondering how complex it could be. Is there already something more known than listed here,
  http://cpcwiki.eu/index.php/ACID
judging from that info, it could be everything... some simple shift/xor logic... but it might also contain kilobytes of encryption data... or even serially transfer program code :-) anyways, it'd be nice to have a look at it, and I won't give up after 3 days if it turns out to be more difficult.
Title: Re: ACID chip inside
Post by: nocash on 02:48, 10 January 10
> For example, LK3 apparently connects 5V supply to Pin28
Correcting myself. LK4 or LK6 seems to be closer to the supply pin. No idea why the table lists LK3 to be shortened for 28pin 64K chips... seems to be a bug in the description (?) especially as it says that LK3 is to be shortened for 32pin 256K chips, too. Which doesn't make too much sense.
Title: Re: ACID chip inside
Post by: fano on 08:01, 10 January 10
Quote from: nocash on 02:36, 10 January 10
That's more or less described / shown on photos, here:
  http://cpcwiki.eu/index.php/GX4000_cartridge

This is a bit short and i am not sure this information is correct.AFAIK there were only 128K commercial productions, some dumps are more than 128K because of the LKs.

Quote from: nocash on 02:36, 10 January 10it'd be nice to have a look at it, and I won't give up after 3 days if it turns out to be more difficult.
I can send you the awfull noexit but i own the pcb without plastic part.Send me a PM with your address.

PS:i found the ultimate book to hack spanish (http://eu.dummies.com/WileyCDA/store/product/Spanish-For-Dummies.productCd-0764551949.html)
Title: Re: ACID chip inside
Post by: nocash on 16:32, 10 January 10
> the awfull noexit but i own the pcb without plastic part.
Perfect. I am living here,
  Martin Korth
  Ernst-August-Deich 59
  21107 Hamburg
  Germany
Title: Re: ACID chip inside
Post by: MacDeath on 17:16, 10 January 10
You're a Hamburger ?

Big Mac ?

(keep on trolling...)
Title: Re: ACID chip inside
Post by: arnoldemu on 10:48, 11 January 10
Quote from: MacDeath on 06:56, 05 January 10
Are there any news about the ACID deciphering project ?
Steve Gane doesn't answer my e-mails.
Title: Re: ACID chip inside
Post by: fano on 12:57, 11 January 10
This is a very bad news  :'(
We were expecting a lot of him  :-\
Title: Re: ACID chip inside
Post by: TFM on 23:40, 11 January 10
Up to now I didn't get an answer from the company which sells the ACID chips.

Has anybody here ordered or is willing to order.

I would take a bigger amount, should shrink the price.

cu. TFM / FutureSoft
Title: Re: ACID chip inside
Post by: dragon on 20:00, 12 January 10
IF they not respond to email,maybe you found they in the  chat :) (you need skype)


skype:ntronics.semiconductor?chat

View the web page,I think  when the icon of chat is in  green colour they are connected.

http://www.n-tronics.com/english/contact/testimonials.php
Title: Re: ACID chip inside
Post by: fano on 20:56, 12 January 10
Interesting.
Give us some news if you success TFM/FS  ;)
Title: Re: ACID chip inside
Post by: OCT on 19:43, 31 January 10
If all else fails, see http://www.heise.de/kiosk/archiv/ct/2008/8/80_kiosk (not free but affordable even if you don't have the paper copy on shelf) and http://sar.informatik.hu-berlin.de/research/publications/SAR-PR-2008-21/SAR-PR-2008-21_.pdf pages 47-48 for an explanation how as a last resort planing and acid could also be used on an ACID (there are also a number of YouTube videos demonstrating the approach).

But we're not even dealing with a present-day crypto processor that would require that level of scrutiny, rather a custom IC that "celebrates" its 20th anniversary while most likely having no idea of time (e.g. for delaying replies to slow down access attempts) - at worst, it should shut down until reset when accessed improperly, but probably not even that.

Clock speeds have increased by 1000 approx. (and memory even more) since the era it was designed in, while the cost and complexity of analyzers (once the domain of advanced electronics manufacturers) has come down from the equivalent of a car in both respects, to rather simple USB dongles no more expensive than the computers they plug into.
Given the hardware developped by people on this forum alone, I'd be surprised if nobody had that kind of equipment available, or worked at places that do.
As a matter of fact, it is already happening, albeit in Spanish (which I can barely decipher let alone translate):
http://amstradcpc.mforos.com/305097/7723493-que-hace-exactamente-el-chip-acid-de-los-cartuchos/?pag=5#80103417
http://amstradcpc.mforos.com/305097/7723493-que-hace-exactamente-el-chip-acid-de-los-cartuchos/?pag=6#80195374
There is speculation in that thread (partly in English) about the ACID being a pseudo random number generator (presumably comes down to some kind of hardware hash), but at any rate this being done by in-house engineers experienced with PALs and GALs of the era (and knowing the 8-bit world's fate, i.e. having to withstand attacks only for limited times), one wouldn't expect something utterly innovative and completely different from what they used in the rest of their designs.
They even called it the Cartridge Gate Array (suggesting a logic chip) in their own Service Manual, for crying out loud: ;)
http://amstradcpc.mforos.com/305097/7723493-que-hace-exactamente-el-chip-acid-de-los-cartuchos/?pag=6#80246125
Title: Re: ACID chip inside
Post by: nocash on 22:33, 31 January 10
Yeah, photos of the ACID chips interiors in (microscopic) super-hi-resolution could be useful. I am a bit surprised that nobody with access to labs has taken such pictures yet, some people do such things for popular console hardware, like NES or gameboy, but probably the ACID is too rare.

I can't translate the spanish forum, too. All I can see, is that they have some nice pictures, at first glance that is. At second glance, the pics look totally off-topic :-) seeing the pretty RAS and CAS waveforms - which have absolutely nothing to do with the ACID chip - I wonder if that guys have at least -begun- to do any ACID rev-engineering.

Send me, send me, somebody a cpc+/gx4000 cartridge! And I'd love to examine how the acid chip works! Btw. Fano, did you found your out-sorted cartridge somewhere?
Title: Re: ACID chip inside
Post by: robcfg on 23:47, 31 January 10
Hi guys,

as far as I remember, the ACID chip (or its absence) prevents acces to RAM or something like that.

I can translate the pages for you, send me a pm with the lin k to the page and I'll try to do it as soon as possible.
Title: Re: ACID chip inside
Post by: redbox on 05:39, 01 February 10
Quote from: nocash on 22:33, 31 January 10
Send me, send me, somebody a cpc+/gx4000 cartridge! And I'd love to examine how the acid chip works!

This website (http://www.tradeinpost.com/gx4000.txt) has some for £7.99 each.

If you're really desperate, then I can buy one and send it to you if it means you can have a go at cracking the ACID  8)
Title: Re: ACID chip inside
Post by: Bryce on 10:28, 01 February 10
Hi nocash,
        a photo of the chips silicon?????? What would you do with it?????? You don't seriously believe you could read this???? For a start, I doubt any 8-Bit hobby hardware person has the equipment to do this and even if they did, do you know how difficult it is to "read" silicon??? I do this stuff for a living and believe me, even with expensive microscopes, multi-angle cameras and fancy template recognition algorythms (assuming you know the structure used in this particular chip) it's still a complete hit and miss exercise and you'd have to destroy quite a few real ACID chips to get any meaningful result.

Bryce.
Title: Re: ACID chip inside
Post by: fano on 13:13, 01 February 10
Quote from: nocash on 22:33, 31 January 10Btw. Fano, did you found your out-sorted cartridge somewhere?
Yes, normaly it will be sent this afternoon  ;)
Title: Re: ACID chip inside
Post by: arnoldemu on 18:22, 01 February 10
Quote from: nocash on 22:33, 31 January 10
I can't translate the spanish forum, too.
http://groups.google.com/group/comp.sys.amstrad.8bit/browse_thread/thread/00621273fbd0f8f4#
Title: Re: ACID chip inside
Post by: dragon on 21:00, 01 February 10
I think the gate array of acid chip contains a maximum of 700 to 1000
logic gates.

Based on the datasheets of gate arrays from the 1990  in different manufacturers.

But the technology that had at that time in the manufacture of gate arrays.It implies that normally could not use 100% of gates.So manufacturers of that time, bought gate arrays with more capacity than they needed.


On the other side.Maybe someone with an oscilloscope could try a Simple power analysis (SPA).That is completely safe for the acid.

http://en.wikipedia.org/wiki/Power_analysis

Maybe not worth much, but to try something different.
Title: Re: ACID chip inside
Post by: nocash on 22:08, 01 February 10
> as far as I remember, the ACID chip (or its absence) prevents
> acces to RAM or something like that.
Yes, its absence. But that's only the "what happens if it isn't there" part. Which is at best mildly interesting. It doesn't matter if the ASIC in the CPC+ scatters RAM or implodes the monitor or whatever.

The important part about the ACID is only the ACID. Which has really nothing to do with RAM. The ACID has only a few pins: A0-A7, CLK, NC, CCLR, SIN, /CE - that's all what counts, and should be trivial to reverse engineer how it works.

> I can translate the pages for you, send me a pm with the
> link to the page and I'll try to do it as soon as possible.
Which link? The link to the spanish forum? See above.
Title: Re: ACID chip inside
Post by: TFM on 22:46, 01 February 10
Since Amstrad was always trying to save some money, I don't consider the acid to be too complex. Maybe a good logical anayzer would do the job. However I don't have one.
Title: Re: ACID chip inside
Post by: dragon on 23:11, 01 February 10
The logic analyzer will attempt in the Spanish forum.

The signal SIN does not seem to follow any pattern.

If you run the same program many times.The SIN  signal is different every time.

http://amstradcpc.mforos.com/305097/7723493-que-hace-exactamente-el-chip-acid-de-los-cartuchos/?pag=5
Title: Re: ACID chip inside
Post by: Grim on 23:23, 01 February 10
I think the ACID is basically an LFSR with the peculiarity that it also takes external inputs (A0-A7 and /CE) into account to generate a new bit to feed it's internal shift register. The SIN signal is the output of the shift register. All the fun is to find out how the internal register (16bit wide I think) and the inputs are ANDed/XORed together to produce this one bit. A logic analyzer might help, but mine, located between my two ears, is very busy and slow :)

Also, I don't think cracking the ACID is necessary to produce new home-brew cartridge. A genuine ACID can be soldered to the back of the cartridge connector inside the Plus. This way, a cartridge would be a simple PCB with an EPROM on it and nothing else (I like KISS compliant solution). It obviously requires to modify the hardware tho, not mentioning it can't be done so easily on a GX-4000 too.
Title: Re: ACID chip inside
Post by: dragon on 20:50, 03 February 10
Interesting theory.The lfsr It has a forbidden state(all 0).

Then if it contains one, can not be initialized in this estate.If the lfsr enter in this state,It wolud remain here indefinitely.

I suppose that the acid will be designed internally to avoid this state.But if this depending on external inputs.Who knows, maybe it is possible to manually cause this condition.And check if it is a sflr.

Indeed, it is possible to construct a logical analyzer, with a simple parallel cable:

http://www.xs4all.nl/~jwasys/old/diy2.html
http://technologyinterface.nmsu.edu/winter97/computers/logic/logic.html
Title: Re: ACID chip inside
Post by: MacDeath on 18:22, 13 February 10
Can we know which company actually built those ACID for amstrad ?

It may still exist ?


Also, do we have a proper schematic of the cartridge ?
I mean, cpcWiki's pages include pictures of cartridge, yet no reall schematics/diagramms...

Title: Re: ACID chip inside
Post by: dragon on 19:00, 13 February 10
Nobody knows who the manufacturer is.But I have a theory.

In the book of the history of Alan Sugar.It is said that the original gate array.He was commissioned to Ferranti.

But they had problems with them.And in the end the gate array was fabricated by SGS.

If the relationship between enterprises continuous throughout the years.(the z80 is a sgs in plus).

It is possible that the acid and asic is a sgs gate array.I think the datasheet from SGS of the year 90 gate array are in the internet.

On the other hand I have seen that there are at least three different versions of the motherboard of the cartridges.

Although the basic design is the same.Change the silkscreen.For example I have one that does not put anything.

But if you see this other cartrige.This fully screenprinted.

http://www.cpcmania.com/Docs/GX4000/GX4000_02.jpg

And this is the other version:

http://www.vieuzordiland.fr/images/stories/gx4000/gx_02.jpg
Title: Re: ACID chip inside
Post by: MacDeath on 19:52, 13 February 10
ASIC and ACID being made by the same manufacturer would make sense of course, as both seem to have to run with each other...

Like a Key and a Lock.

Also as the only custom chips, those would apparently be done by the same.


Yet Do we have a proper schematic of the cartridges ?

Or even is this cartridge schematic added on the Mother board schematic ?
I mean, if connected, it's actually part of the motherboard then.


I'll take a look at that.


Title: Re: ACID chip inside
Post by: Grim on 23:29, 13 February 10
QuoteDo we have a proper schematic of the cartridges ?
The attachment below is the schematic of the system cartridge (BASIC & Burnin Rubber in a 128K-27C1001 EPROM).
Title: Re: ACID chip inside
Post by: MacDeath on 06:46, 14 February 10
http://events.ccc.de/congress/2008/Fahrplan/attachments/1218_081227.25C3.HardwareReversing.pdf

Just a link on the matter of reverse engineering hardwares.

Perhaps we should simply "sand" an acid chip ???
A friend of mine work as a "metrologue".
His worrk is to measure mechanical pieces with greatest precision to tell producers if their pieces respect the specs.

But so he has access to a nice set of modern precision video system, with ability to do extra zoomed clear pictures...
Yet the "sanding a chip" is delicate and would awfully kill the list beast.
:'(


I'll be searching for other articles on the matter of reverse engineering microchips and integrated circuits.

Yet we also must remind that dating from 1990, the ACID chip is not the miniaturised bastard of the modern era such as a square128x128pined  BGA surface mounted component.
(totaling in 16384 pins...)

Let's say it must have a few copper layers with a few semiconductor spots between hard silicon...
Perhaps a small memory like stuff ?

Also there :
http://www.tmplab.org/wiki/index.php/Chip_Reverse_Engineering

There is a mention of Karsten Nohl (who did the document of my first link).
Perhaps we should contact this person ?
http://www.cs.virginia.edu/~kn5f/index.html
But he must have no time for us, he may see not point nor time in our Amstrad fanboyoism... ;D

another article from the man.
http://www.flylogic.net/blog/?p=32

He 's actually German, graduated in USA... Yet seems to live/work in Berlin.

Can some german fellows here get in touch with him ?
Yet he seems to be a busy man and ACID and retrojunk may not be his cup of tea (of barrel of beer...mmmh...).

If someone has access to a sweet digital microscope, and is willing to sacrifacie an ACID chip (a GX4000 burnin'Rubber may be the cheapest solution, can buy it for 5 €uros...)
just unsolder the chip, glue it on a support/base.
Then find a proper way to sand if slightly and gently, take pictures often with the microscope of the different layers.


I don't think ACID to be a really complicated security Hardware.
just a few simple logic fonctions and a ROM like data key perhaps.

Of course doing the same with an ASIC would be great too, yet a bit more complicated and delicate of course.
Bigger chip, and a shitton of fonctions, also memories spaces (Ram for the sprites, perhaps for the sound processor too ?)

There are companies who do that professionally.
Just have to see how much would it cost, as we may not need a complete analysis, just getting the basic schematics as many of you are great electronicians with a deep knowledge of the Amstrad logic, enough to understand the schematic by ourselves...

Because they have the right machines to do that, just sanding and photograph the chip is a trivial job for them.
This would be a much fiable solution as amateurishly sanding a chip may not be that easy.

Would need a trainning on a useless microchip first just to get the hand on the proper force to put in the sanding and the right "sand-paper" grain (or a proper file tool...).


http://www.selfworld.net/room_medias/8#
"GSM Rainbow tables & microchip reverse engineering "


Of course the "black box" anaysis started by our español fellows are usefull too, perhaps, yet the "HardCore" way seems the...most able to produce actual results.

Also, perhaps helpfull videos :

http://vimeo.com/3081101


oh, out of topic, yet fun, I I found this new video host site with computer related videos :
http://vimeo.com/3082459
commodore64 history.
Would be great and neat to have a video like this on Amstrad CPC... ;)

http://vimeo.com/2622333
A türk demoparty/retrocomparty with some of the peoples there having... Amstrad's computers.

http://vimeo.com/5270825
amstradcpc.com.
yet tis video seems more Amiga related, but the site exists, it is a türkish retrocomp site with an obvious name.
Strange this guy don't seems to come visit us but he may have good knowledge perhaps, yet my Türk sucks deeply.
(Hey Gryzor, you don't live fare from Türky, as they are your direct neighbours...)


Also, back to topic...
http://www.ccc.de/de/
German fellows Amstradists may look at this association perhaps, some poeple there would be willing to halp.
http://en.wikipedia.org/wiki/Chaos_Computer_Club

Pledging our cause may work for the sake of it, as Amstrad's PLUS' ACID and ASIC may even be trivial for them...and is some kind of symbolic as it would actually "save" the Amstrad Plus range.
Title: Re: ACID chip inside
Post by: OCT on 09:03, 14 February 10
Quote from: nocash on 23:51, 09 January 10
> Spanish Amstraders are actually trying to analyse it properly.
If somebody should happen to want to donate a cartridge, and maybe even a gx4000, I am sure I could figure out how it works in 2-3 days - you can make jokes on me for the rest of my life if I can't :-)
Quote from: Grim on 23:29, 13 February 10
The attachment below is the schematic of the system cartridge (BASIC & Burnin Rubber in a 128K-27C1001 EPROM).
So what goes in besides the clock and power lines is just CCLR plus the lower byte of the address bus, all combined somehow into one single SIN bit of output at a time.
If CCLR is a reset line, that might indicate a shift register. Otherwise the chip might just be performing logic operations, one byte at a time, or even await Yet Another Magic Sequence, but that would probably have been too easy to overcome even for its age.
Taking it apart physically would probably use a few dozen of these chips though (and yet we do know who's got hundreds in stock at 4 Euros apiece).
Either way, I'd find it hard to believe that given the limited amount of input and output involved, one couldn't figure things out with the memory and analyzers available today.
Can't help wondering what signals the Spanish forum has been looking at, though... (but anyone going to Spain next month, by all means do source the mold&maker of these marvelous ZIF-socket cartridges (http://cpcwiki.eu/index.php/CPC_GX4000-Multi_EPROM_Cartridge))
Title: Re: ACID chip inside
Post by: MacDeath on 09:40, 14 February 10
I shall spill the blood of a thouzand spanish amstradist to find it !!!
;)

Yet this sweet and well done multieeprom cart seems to miss the LKs...
Has anyone tested the LKs ?
Would it blown up the Amstrad to do the wrong LK config ?

Also I think a proper testing Software is needed to actually test the cartridges, with for exemple 256Ko or 512Ko Roms, to find where Datas are stored and how to access them, with the different LK settings ..


I don't think so many ACID need to be sacrified to perform a Hardware retroengineering.
Professionnal would actually find it quite trivial as they may have the equipment to perform such task on modern highly miniaturized chips.
Yet it would be great to check such company to know the price of this.

And we must also check if the so called "ACiD stock" is a fact or a fiction...Buy some perhaps or even go directly too the company pretending to be selling some to verify if those are really what we expect.
(thus reducing the shipment fee perhaps)
Title: Re: ACID chip inside
Post by: dragon on 12:53, 14 February 10
QuoteAnd we must also check if the so called "ACUD stock" is a fact or a fiction...Buy some perhaps or even go directly too the company pretending to be selling some to verify if those are really what we expect.
(thus reducing the shipment fee perhaps)

The true vendor of acid is in netherland(ntronics is an intermediate):
http://www.brokerforum.com/electronic-components-search-en.jsa?originalFullPartNumber=IL03P1003&x=0&y=0&hasNoSearchCriteria=false&searchPartNoLabelValue=Search+Part+Number

Brokerforums support trival versión.If anyone is encouraged to register, it's easy to find out who really sells the chips.

What they do(ntronics) is see this page.

On the other hand, the ASIC contains 18,000 gates. (Puts it in the service manual).

Ah another new intermediate shop:

http://www.powercomponents.nl/webshop/index.aspx?a=3&artcode=IL03P1003

QuoteSo what goes in besides the clock and power lines is just CCLR plus the lower byte of the address bus, all combined somehow into one single SIN bit of output at a time.

The cclr signal is a strange signal.It behaves differently if the acid is or not.

If the acid is present. the signal cclr is continuous.But if its not present.The signal produces periodic pulses.
Title: Re: ACID chip inside
Post by: OCT on 13:37, 14 February 10
Quote from: dragon on 12:53, 14 February 10
On the other hand, the ASIC contains 18,000 gates. (Puts it in the service manual).
[...]
The cclr signal is a strange signal.It behaves differently if the acid is or not.

If the acid is present. the signal cclr is continuous.But if its not present.The signal produces periodic pulses.
Sounds to me like it is periodically trying to trigger a sequence of communications with the ACID, probably by resetting it. I'd venture a guess that even with the ACID present, CCLR will probably show at least one (series of) pulse(s) on startup, while putting a number of addresses on the bus and monitoring for SIN to say what a good ACID should.
The fact that CCLR keeps "blinking" periodically when no cartridge has been detected is a good sign, for it suggests the ACID won't lock itself down until the next power cycle/"hard reboot" for the whole system when a sequence fails (otherwise there'd be no point in retrying).
Does SIN keep changing even after the pulses on CCLR have ceased?
Whatever SIN is (logically rather than theologically ;)), it must be simple enough for the CPC+'s ASIC to pre-compute as well from the address (+maybe CCLR) bits and compare to that bit - so on an analyzer, running a few gigabytes (not actually if we're just talking 2^(8 or)9*length_of_register bits) through the circuitry with the clock and blips of CCLR applied might already do the trick.
But first of all, one should capture the address byte on every "blink" of CCLR while there is no ACID - maybe things are even easier than we think and the ASIC does actually try a magic sequence that always starts with the same address.
With the ACID connected again, counting the pulses per series (assuming there is at least one of these even then, and that CCLR is not a chip reset, in which case one would have to count the clock cycles until SIN stops changing) should indicate the length of the PRNG shift register (or whatever it is), i.e. the number of addresses evaluated as input.
At any rate, from the circuit diagram I doubt the RAM that the Spanish have focused on is involved in what goes on between ASIC and ACID - unlocking the hardware to the cartridge seems to be what the ASIC does after successfully verifying the ACID.
Title: Re: ACID chip inside
Post by: nocash on 03:03, 16 February 10
Hi! Got the cartridge from fano (thanks!) and started to work on it saturday. First day I've wasted on unimportant stuff, desoldering the chip, verifying the pin-outs, nothing really required, but it's a nice way to get familar with the hardware :-)

The cartridge pin-outs are the same as the known A1-A18 and B1-B18 pin-numbers. Though counted differently (odd pins: CartPpin1..35 = CpcPinB18..B1, and even ones: CartPin2..36 = CpcPinA18..A1.

The six LKs are for A15,A17,A18 (address lines, of course, not the "A1-A18" pins).
  VCC ---LK1--- EPROM.A18---LK2---CPC.A18
  VCC ---LK3--- EPROM.A17---LK4---CPC.A17
  VCC ---LK5--- EPROM.A15---LK6---CPC.A15
My cartridge PCB doesn't have any LKs installed, instead, the etched circuit has hardwired connections between some of them. One could scratch them off, and then use the LK soldering points to reconfigure the board for eproms of other size.

----

Okay, now to the ACID. The pin-outs listed on cpcwiki are correct, not much new new there. The two GND pins are really both GND (they are interconnected with each other inside of the chip). The NC pin seems to be always high.

For testing I've simply wired the chip to the parallel printer port on my PC. A0-A7=Data0-7, OE=SELECT, CLK=STB, CCLR=INIT, SIN=BUSY.
Of course, the PC's I/O waitstates are making the transfer a bit slower than on the CPC, instead of 4MHz, I can't get CLK faster than 200kHz or so. Been a bit worried that it could cause problems (in case there'd by any stuff like dynamic refresh going on). Fortunately, it works 100% stable, I can even run a mp3 player in background.

SIN outputs the serial data stream to the CPC. CCLR is an input, setting it to LOW does reset the chip, which is (on a CPC) probably done only once at power-up to sync ACID and ASIC, or in case of errors (which would explain why people reported it to toggle on/off when cartridge is connected).

Aside from synchronizing, CCLR is (sometimes) also needed to get the ACID to output anything at all. I had a funny situation where SIN did output data all fine, then switched off the computer for a while - and when I wanted to continue SIN didn't output anything but zeros :-) took me quite a while to figure out why it didn't work anymore (needed to drag CCLR=LOW for a moment, then it started to send data).

----

Now to the data stream - after reset via CCLR, it outputs 16 high levels on SIN (one per CLK), and then starts to output "random" bits. So it's quite obvious even at first glance that the ACID is some simple shift-xor stuff, ie. as used in noise generators in sound chips.

Only problem is that one sees only one bit at a time (not the whole value in the shift register). Which made it a bit difficult to find out how it works: The shift register is 17bits wide, one bit is output on SIN, four bits are XORed with each other, shift occurs once per CLK cycle, and the XORed bits are shifted in at the top (or bottom, whatever you turn it around).

My test proggy can calculate the data stream by software, and it matches up perfectly with the data coming from the ACID chip. So that part is solved.

----

The other part - that I've more or less ignored for now - is the 9bit data bus, fed by the A0-A7 and /OE signals. The interesting part here is that the hardware is more or less ignoring it, too.

After CCLR=LOW, the first some thousands bits on SIN are usually always the same, no matter what is injected on the 9bit data bus. In many cases its even the complete data stream (not just only the first thousands bits) unaffected by the data.

Checking what is going on there will be my next step. My current bet is that the hardware does something like
"IF ValueOnDataBus = ValueInShiftRegister THEN toggle some bits"
which would explain why it reacts to incoming data only once every some thound cycles. If it that simple, then I am about half done with reverse engineering :-)

Cu, Martin
Title: Re: ACID chip inside
Post by: redbox on 04:32, 16 February 10
Quote from: nocash on 03:03, 16 February 10
Hi! Got the cartridge from fano (thanks!) and started to work on it saturday.

Even with my very limited electronics knowledge, this is really interesting to read.

Keep us updated as you try and crack it.  :)
Title: Re: ACID chip inside
Post by: Grim on 08:44, 16 February 10
Could you confirm that the feedback fonction is :
feedback=b0 XOR b4 XOR b7 XOR b16

with b16 being the SIN value and feedback being the bit shifted in the register (in b0). Please?

Thank you! :)
Title: Re: ACID chip inside
Post by: MacDeath on 13:47, 16 February 10
(http://maddok.files.wordpress.com/2009/09/proceed1.jpg)
Title: Re: ACID chip inside
Post by: nocash on 15:56, 16 February 10
> Could you confirm that the feedback fonction is :
> feedback=b0 XOR b4 XOR b7 XOR b16
> with b16 being the SIN value and feedback being
> the bit shifted in the register (in b0). Please?

I am shifting right (other way around), so, in that way, your values would be:
  newbit16 = oldbit16 xor oldbit12 xor oldbit9 xor oldbit0
yup, that are the same bits as the ones I am using.
I am using oldbit1 (aka newbit0) for SIN,  though that just matters on whether you do the calculation before or after the CLK pulse.

How did you find the bits? Did you connect the ACID chip to a PC, too? Thought I'd have been the first one having that idea, then on the other hand it's so obvious to do it, that other people probably had the idea too :-)

Apropos, anybody seen this one?
  http://v3.espacenet.com/publicationDetails/biblio?CC=GB&NR=2243701A&KC=A&FT=D&date=19911106&DB=&locale=
  link to a patent rumoured to be ACID's patent.
Guess (hope) everybody who ever made a CPC+ program will say:
"Errrr, no, that's something well known, and it's really not ACID." :-)

About the data inputs, /OE is simple. If it's high, then the data stream advances in normal way. If it's low, then the A0-A7 are somehow compared with the shiftregister, and if the values do match, then some bits are modified.

How the comparision & modification works exactly is still unclear to me. I can reproduce the effect for a dozen of values, and hoped I could calculated the remaining values from them. Ie. hoped that, if I know the effects on address=01h and on address=08h, for example, then address 09h should have the two ones XORed together - but that theory didn't worked, or I did something wrong :-)
Title: Re: ACID chip inside
Post by: MacDeath on 17:34, 16 February 10
This patent talks a lot about the locking and unlocking of Extra Plus features.
it talks about a new computer having to be compatible with ancient computer but having also additionnal features, yet those additionnal features should be locked in order to run old computer's programms...


Do you think the ACID has a role in this ?
We know it is possible to unlock the Extra PLUS features, but Amstrad said at the release of Plus range that only cartridges/cartridges games enabled Plus features.

Yet we know it isn't true, yet after all, running a PLUS still needs an ACID...
So running PLUS features may too.
Title: Re: ACID chip inside
Post by: Grim on 17:54, 16 February 10
QuoteHow did you find the bits? Did you connect the ACID chip to a PC, too? Thought I'd have been the first one having that idea, then on the other hand it's so obvious to do it, that other people probably had the idea too :-)
I've put the ACID on a breadboard and connected it to the printer port of my CPC (taking the +5V from the expansion port). I wrote a small MC program to simulate the CLK, perform the CCLR initialization and then read/transmit the SIN pattern to the PC with a CPCBooster (RS232). It takes about 5 minutes to record 2-MByte of data.

The first 3 bits of the feedback function were easy to find by just looking at the first bits of the SIN pattern. But it took me a while to figure out the 4th bit because for some reason I assumed a 16bit wide shift register... missing one bit :)

Now I'm also trying to find out how the 9bit inputs affect the shift register. Right now I'm focusing on two SIN recordings; one that I can exactly reproduce with the feedback function, and another one which was recorded with some input bits set so the pattern differs at some point.

I intend to perform an almost-smart-brute-force attack to find out the relation between the inputs and the bits of the shift register. Dunno if it will work and how much time it will take to compute (It's written in PHP :).

QuoteThis patent talks a lot about the locking and unlocking of Extra Plus features.
This patent describes the locking mechanism of the RMR2 register (allowing to page in/out the ASIC registers and ROM stuff). It has nothing to do with the ACID.
Title: Re: ACID chip inside
Post by: nocash on 20:04, 16 February 10
Got it! Fixed some mistakes in my proggy, found out that one of the 17 bits is ignored in the comparisions. And now the compare/adjust stuff is working fine :-)

   @@xlat macro nn,cmp_val,xor_val
     test byte ptr ds:[lpt_data],1 shl nn
     jz   short @@skip_&nn
     xor  dword ptr ds:[@@cmp_val],cmp_val
     xor  dword ptr ds:[@@xor_val],xor_val
    @@skip_&nn:
   endm
   ;---   bit,compare,xor
   mov  dword ptr ds:[@@cmp_val],13596h
   mov  dword ptr ds:[@@xor_val],0c820h
   @@xlat 0  ,0000ch ,00004h
   @@xlat 1  ,06000h ,06000h
   @@xlat 2  ,000c0h ,00080h
   @@xlat 3  ,00030h ,00020h
   @@xlat 4  ,18000h ,08000h
   @@xlat 5  ,00003h ,00000h
   @@xlat 6  ,00600h ,00000h
   @@xlat 7  ,01800h ,00800h
   test word ptr ds:[@@dat],100h ;OE=High
   jnz  short @@not_here
   mov  eax,dword ptr ds:[@@cmp_val]
   xor  eax,dword ptr ds:[@@shift_reg]
   and eax,not 100h
   jnz  short @@not_here
   mov  eax,dword ptr ds:[@@xor_val]
   xor  dword ptr ds:[@@shift_reg],eax
  @@not_here:
;---now advance shift reg
@@mod macro nn
  mov  ebx,dword ptr ds:[@@shift_reg]
  shr  ebx,nn
  xor  eax,ebx
endm
xor  eax,eax
@@mod 0
@@mod 9
@@mod 12
@@mod 16
and  eax,0001h
shl  eax,17
xor  dword ptr ds:[@@shift_reg],eax
shr  dword ptr ds:[@@shift_reg],1
;---isolate SIN
mov  eax,dword ptr ds:[@@shift_reg]
and  eax,0001h

That should be all about the ACID chip. I think everything is reverse engineered now, there should be no further secrets.

Let's see, 13th-16th February, 4 days altogether. Hmmmm, I claimed I could do it in 2 days, damn :-) but it's been a funny action-research time. Didn't do that kind of stuff for a while. Maybe I should go on with the NES, it has a similar chip - does somebody know if it's still unknown how the lockout chip in NES works?
Title: Re: ACID chip inside
Post by: OCT on 20:24, 16 February 10
Quote from: nocash on 20:04, 16 February 10
Got it! Fixed some mistakes in my proggy, found out that one of the 17 bits is ignored in the comparisions. And now the compare/adjust stuff is working fine :-)
Congrats! :) This looks a lot like it wants to become a PAL/PIC/AVR/whatever... ;)
Title: Re: ACID chip inside
Post by: dragon on 21:04, 16 February 10
nocash I only can say.You are a monter. :o

Title: Re: ACID chip inside
Post by: Octoate on 21:05, 16 February 10
Congrats! Great to see the secrets of the last chip seems to be determined :).

nocash: is it possible that you can write how it works in a kind of pseudocode or do a small diagram of it (if you have time to do that)? Not all users (especially me ;)) are able to read x86-ASM.
Title: Re: ACID chip inside
Post by: dragon on 21:11, 16 February 10
Or best,you can write a circuit with logical gates using xilinx maybe?.And put the picture.?
Title: Re: ACID chip inside
Post by: redbox on 21:59, 16 February 10
Quote from: nocash on 20:04, 16 February 10
Got it! Fixed some mistakes in my proggy, found out that one of the 17 bits is ignored in the comparisions. And now the compare/adjust stuff is working fine :-)

Does this mean we now can bypass the ACID chip and use something else instead to make our own cartridges?
Title: Re: ACID chip inside
Post by: OCT on 22:18, 16 February 10
Quote from: redbox on 21:59, 16 February 10
Does this mean we now can bypass the ACID chip and use something else instead to make our own cartridges?
Yup. :D
Implementing nocash's algorithm (http://cpcwiki.eu/forum/index.php/topic,410.60.html#msg5529) in a microcontroller, we could even use its outputs to toggle the chip-enables (and/or an extra address line) of one of several EPROMs (SMD if need be) crammed into one "monster" cartridge with a menu that triggers the final ROM selection, recreating the demonstrator (http://cpcwiki.eu/index.php/GX4000_cartridge#Demonstration_System) in a much smaller form factor. Or even a "remote reprogrammer" with some kind of Zigbee/Bluetooth or similar (of which there are implementations aplenty for various microcontrollers) in the cartridge, which would use an EEPROM like the SYMBiFACE II and be fed the appropriate ROM image via wireless RF from a PC.
Wish I had some dev gear (and a Plus!) around here to join in the fray...
Won't be long before we get the likes of SymbOS and FutureOS on "homebrew" cartridge either I guess.
Title: Re: ACID chip inside
Post by: dragon on 22:18, 16 February 10
QuoteLet's see, 13th-16th February, 4 days altogether. Hmmmm, I claimed I could do it in 2 days, damn :-) but it's been a funny action-research time. Didn't do that kind of stuff for a while. Maybe I should go on with the NES, it has a similar chip - does somebody know if it's still unknown how the lockout chip in NES works?

You can see the know about nes chip here:

http://hackmii.com/2010/01/the-weird-and-wonderful-cic/
Title: Re: ACID chip inside
Post by: redbox on 23:24, 16 February 10
Quote from: OCT on 22:18, 16 February 10
Yup. :D
Implementing nocash's algorithm (http://cpcwiki.eu/forum/index.php/topic,410.60.html#msg5529) in a microcontroller, we could even use its outputs to toggle the chip-enables (and/or an extra address line) of one of several EPROMs (SMD if need be) crammed into one "monster" cartridge with a menu that triggers the final ROM selection, recreating the demonstrator (http://cpcwiki.eu/index.php/GX4000_cartridge#Demonstration_System) in a much smaller form factor.

Wow, this sounds truly awesome!!!  I salute you nocash  :)

I'm going to have to get into this and start brushing up on some electronics. 
Title: Re: ACID chip inside
Post by: MacDeath on 05:08, 17 February 10
Ok, so now we have to figure clearly how to use 256ko and 512ko Roms on thoses cartridges, and also how to do GX4000 compatible programms/games, with "easy" howtos.


Concerning the GX4000 incompatibility of the existing bootlegs carts, it must come from the fact those are often CPC games simply put into carts, so the keyboard may still be needed... rendering the GX4000 unfit.

Yet I've read that the GX4000 has really some differences from 6128Plus/464Plus.
What are they ?

A Symbos "lite" version runing from a cart yould be great.
Or any OS...

An advanced Cartridge with the good old Basic, an advanced "Plus" basic, C/PM-Dos like OS, and perhaps a GUI...

Or else a complete PLUS Development applications kit put on ROM is clearly a great possibility.
Music and sounds Programs too.

And we know 512Ko is really more than enough to do awesome stuff on the Amstrad.
512Ko + a disc Drive is perhaps at last "a dream comes true", to unleash the beast.

Would reduce the need to get Ram/Rom boxes a bit...

To design a proper modern MultiEprom Cartridge will really be a turning point, a milestone, and getting GX4000 compatible new productions the start of a new retro-life for all those covered in dust in the many consoles collections.

When this is verified, tested and approuved with this implemented in a programable Chip/Microcontroller or whatever, we must find the cheapest componnents able to do it, design a proper board, find the good and cheap components...

And manage a "production".

No need to get a Manufacturer to solder or assemble thoise.
Just gathering componnents as "solder/assemble it yourself" kits.
So only the Printed circuit is to be produced, the rest just bought in good quantity to enable cheaper price.
Yet ideally, a plastic Body/box would be sweet too...

Getting all those programable chip programed...would be the longer part perhaps.

And here we are.
We all got our longly awaited Multi eprom Carts...Soon ?


Thx to Fano for the sacrifice of one of his Cartridge.

Thx to Nocash for the sacrifice of 4 days.
:-*


It took 20 years and 4 days.


then THE question :
Who will release the first 512Ko cartridge Amstrad Plus' MegaDemo and win all 8 bit Demo competitions with it ???
Title: Re: ACID chip inside
Post by: fano on 07:31, 17 February 10
OMG :o he did it ! congratulation Martin !
Title: Re: ACID chip inside
Post by: nocash on 09:07, 17 February 10
Many thanks for the cartridge, fano. Been fun to play with it!
I mean, play with the chip, not with the game.

Here's the pseudo code. Basically it repeats every CLK cycle.

if PinCCLR=0 then ShiftReg=1FFFFh
CmpVal=13596h, XorVal=0c820h
if PinA0=1 then CmpVal=CmpVal XOR 0000ch, XorVal=XorVal XOR 00004h
if PinA1=1 then CmpVal=CmpVal XOR 06000h, XorVal=XorVal XOR 06000h
if PinA2=1 then CmpVal=CmpVal XOR 000c0h, XorVal=XorVal XOR 00080h
if PinA3=1 then CmpVal=CmpVal XOR 00030h, XorVal=XorVal XOR 00020h
if PinA4=1 then CmpVal=CmpVal XOR 18000h, XorVal=XorVal XOR 08000h
if PinA5=1 then CmpVal=CmpVal XOR 00003h, XorVal=XorVal XOR 00000h
if PinA6=1 then CmpVal=CmpVal XOR 00600h, XorVal=XorVal XOR 00000h
if PinA7=1 then CmpVal=CmpVal XOR 01800h, XorVal=XorVal XOR 00800h
if PinOE=0 AND (ShiftReg OR 100h)=CmpVal then ShiftReg=ShiftReg XOR XorVal
NewBit=ShiftRegBit0 XOR ShiftRegBit9 XOR ShiftRegBit12 XOR ShiftRegBit16
ShiftReg=(ShiftReg SHR 1) + (NewBit SHL 16)
PinSIN=ShiftRegBit0

Guess I should do some extra tests on the timings. At the moment, I couldn't say if /OE is processed on raising or falling edge of CLK, or independently of CLK, on raising or falling edge of /OE itself.

Hmmmmm, just noticed, the smileys are now animated :-/ is that new? Something wrong with this century, they have no nose, but they are in color and do twinkle. Only wonder how long it takes until somebody invents smileys with audio layer.

> http://hackmii.com/2010/01/the-weird-and-wonderful-cic/
Wow. Cool. If the date is correct, it seems to be only a month ago that the NES chip was rev engineered. With the 4bit cpu it's a good bit more complex than the acid, must have been a damn interesting project to decipher the instruction set.
Title: Re: ACID chip inside
Post by: Octoate on 09:37, 17 February 10
Quote from: nocash on 09:07, 17 February 10
Here's the pseudo code. Basically it repeats every CLK cycle.
...
Thanks a lot. That's more understandable for me :). I hope that I have the time to play a bit with it during the weekend.

Quote from: nocash on 09:07, 17 February 10
Only wonder how long it takes until somebody invents smileys with audio layer.
Oh no... please not :)!
Title: Re: ACID chip inside
Post by: Bryce on 09:41, 17 February 10
Impressive work nocash, well done. Are you going to put together the hardware solution for the crack cartridge too now? It looks like it could be done either with regular TTL chips or (probably a neater solution) emulated in a low-cost PIC.

It also looks like the chip reacts very similar to the patent you mentioned earlier (using a PRBS Generator or similar), have you checked whether the ACID is reacting in a similar way? Or maybe the ACID is an adaptation or progression of the patent?

I had been looking for a CPC+ and cartridge to crack the ACID myself, but now I want one even more, just to try out the crack :)

Bryce.
Title: Re: ACID chip inside
Post by: arnoldemu on 10:58, 17 February 10
Quote from: nocash on 09:07, 17 February 10
Many thanks for the cartridge, fano. Been fun to play with it!
Great work nocash!
I am really impressed by how quickly it took you to do this.
I too would love to eventually see a cartridge PCB with PIC on it emulating the ACID.

Ok, now it's time to start converting and enhancing lots of games for cartridge ;)

And now, maybe you have now either opened the flood gates for the Polish to mass produce cartridges at crazy prices, or you have now forced them to lower their prices  ;D



Title: Re: ACID chip inside
Post by: MacDeath on 11:07, 17 February 10
And it cost us no ca$h...
:D
Title: Re: ACID chip inside
Post by: deepfb on 11:22, 17 February 10
Congratulations, nocash!!
...And some hurrahs for you from spain:

http://www.zonadepruebas.com/modules/newbb/viewtopic.php?topic_id=7991&forum=2&post_id=66723#forumpost66723

http://amstradcpc.mforos.com/305097/7723493-que-hace-exactamente-el-chip-acid-de-los-cartuchos/
Title: Re: ACID chip inside
Post by: dragon on 12:17, 17 February 10
Hey nocash if you emulated the acid in pic,you need search a name for the new chip.

UCID maybe?(users cartridge identification device) :).
Title: Re: ACID chip inside
Post by: MacDeath on 12:37, 17 February 10
ACID is a drug...
Crack is a drug too...

CRAK chip ?
Or HEMP ?
WEED chip ? ;D

Or Amstrad Cracked Identification device ? simply...

BTW, I modified the ACID cpcwiki page for the occasion.


Also, you spanish Amstraders...you have some experience in Cartridges, would you help and share with the rest of europa ?

I hope those would be available in Madrid, next month....
Title: Re: ACID chip inside
Post by: Bryce on 12:50, 17 February 10
How about "Base" or "Alkaline" ie: Neutralises Acid.

Bryce.
Title: Re: ACID chip inside
Post by: Octoate on 14:19, 17 February 10
Quote from: MacDeath on 12:37, 17 February 10
BTW, I modified the ACID cpcwiki page for the occasion.
I saw that, but TBH, I don't like the way, the page currently looks. Now the ACID article doesn't show the technical data of this chip but your little story about "The End of the Darkness". If you want to keep that, you should either move that story to be the last chapter of this article or to the talk page. This is just my opinion, maybe others like it...
Title: Re: ACID chip inside
Post by: Ygdrazil on 15:13, 17 February 10
I think Octoate is correct  ;D

Maybe the story could be moved to be the last chapter of the arcticle, factual information first... !

/Ygdrazil

Quote from: Octoate on 14:19, 17 February 10
I saw that, but TBH, I don't like the way, the page currently looks. Now the ACID article doesn't show the technical data of this chip but your little story about "The End of the Darkness". If you want to keep that, you should either move that story to be the last chapter of this article or to the talk page. This is just my opinion, maybe others like it...
Title: Re: ACID chip inside
Post by: MacDeath on 15:32, 17 February 10
Fixed.

Concenring my text :

of course it bring no technical stuff, yet it was a humorous way to mark the event.

It may be removed or put Elsewhere then (a page in Amstrad History perhaps ?), once the technical stuff are added.

That's the good thing with a Wiki : such thing are not definitive.


I let to better technicians than me the job to add the technical and serious stuff.

Then I'll put my "writefaggotry" elsewhere, perhap at the NoCash page ?

QuoteHalf of spain probably already has a soldering iron in their hand
Or even notorious Polish Bootlegers...

Also I just found this :
http://poubelles.be/forum/viewtopic.php?id=2999&p=3

It was about time ACID to get cracked.

This website is about people recycling electronic component to extract valuable metals.
And one of the guy sems happy that the Amstrad Cartridge is full of valuable stuff to recycle.

OMG, he aim to destroy it ? how many has he already destroyed ?
It's even a Basic Cartridge, the one needed to run the computer.

I'm sure such guy found and destroyed the entire Chase HQ unreleased stock, and even GAZZA II 's cartridges...
Title: Re: ACID chip inside
Post by: Bryce on 15:46, 17 February 10
"The end of darkness" is well written and humourous, but I find it takes away from the technical achievement, results and data a little. I'm sure nocash will have enough content to fill the ACID page with tonnes of technical information within the next few days/weeks and maybe (hopefully) even a picture of the setup he used. Did you (nocash) document (ie: take loads of pictures of) the project as it progressed? I'm also looking forward to the first implementations of this information. Half of spain probably already has a soldering iron in their hand :D

Bryce.
Title: Re: ACID chip inside
Post by: robcfg on 18:19, 17 February 10
I'm already warming the soldering iron...  ;D
Title: Re: ACID chip inside
Post by: OCT on 21:01, 17 February 10
Quote from: MacDeath on 12:37, 17 February 10
ACID is a drug...
Crack is a drug too...
[...]
WEED chip ? ;D
As in:
Wireless EPROM Emulation Device ? ;)
Would be most appropriate if you actually get the microcontroller to talk Bluetooth for EEPROM downloads over the air (http://cpcwiki.eu/forum/index.php/topic,410.75.html#msg5537) (so no cable will ever be literally a "terminal" one anymore, zapping one of the computers involved due to the difference in potential).

QuoteAlso, you spanish Amstraders...you have some experience in Cartridges, would you help and share with the rest of europa ?
I hope those would be available in Madrid, next month....
So to flatteringly win their favours it's gotta be named El Cid, then. :D
For we know The Force is strong in these ones (http://cpcrulez.free.fr/hardware_GX4000-Multi_EPROM_Cartridge.htm)...
Well, since we're not the Illuminati it can't be too close to Heute Hanf, morgen Hanf, immer Hanf all the time anyway. ;)
Title: Re: ACID chip inside
Post by: Trebmint on 23:26, 17 February 10
Does this mean we should all start writing 512Kb Plus games then? Liking that idea
Title: Re: ACID chip inside
Post by: OCT on 23:42, 17 February 10
Trebmint: Exactly. And with even the last bit of protection pried wide open now, got to release them for free (well, there hadn't been a commercially viable market for CPC games for a decade and a half anyway) as there'll forever be nocash (congrats again, pun intended ;)).

Quote from: Bryce on 12:50, 17 February 10
How about "Base" [...]: Neutralises Acid
With the added advantage of being a very fitting retro reminder of the immortally memed Zero Wing (http://en.wikipedia.org/wiki/All_your_base_are_belong_to_us):
(http://upload.wikimedia.org/wikipedia/en/0/03/Aybabtu.png)
(As recycled in: PH34R R L33T SK1LLZ :D)
Title: Re: ACID chip inside
Post by: Grim on 02:10, 18 February 10
Just verified Nocash's algorithm against real ACID SIN output, it works great! :)

Congratz dude! If you're looking for other chips to crack, there's the 3 PALs of the Multiface Two waiting for you (I bet on 3 days :)
Title: Re: ACID chip inside
Post by: nocash on 02:33, 18 February 10
Hi, updated the ACID page (with the description I had already posted here). And moved the patent info to
http://cpcwiki.eu/index.php/Programming:Unlocking_ASIC that's the stuff you sent to the CRTC index register (it has nothing to do with the ACID, the only relation is that somebody at Amstrad liked to use shift registers).

Oh, and I have no plans to implement an ACID-clone in hardware, I've never used PALs, so I'll leave that part to somebody else.

Doing it with 74xx logic chips would work, too. And, as a prototype, it'd be nice, as one could "see" how it works (unlike a PAL where you don't see what is inside it). Anyways, that'd require a fairly huge circuit with about 10 chips. If anybody wants to make more than one cartridge, a single chip PAL solution would be better.

Using  PICs... aren't that software controlled microprocessors? Not too sure if that could work. The stuff must be processed at 4MHz, to implement that in software, the CPU would need to run at 100MHz or so. Dunno if modern PICs are that fast.

---

So, and cheating around fully implementing the ACID...

I guess one cannot get around implementing the shift-register - but, one could omit the compare/adjust part. The comparision matches are occuring only once every some ten-thousand CLK cycles.

If the CPU and ACID are reset at the same time (no idea if it's like so) then the software could take care not to access EPROM addresses at times that are known to cause matches. The timings would be difficult to implement.

An easier way to cheat would be this: After CCLR, matches occur only on about 131 addresses (eg. addr=00h), so the remaining 125 addresses (eg. addr=01h) can be safely accessed. Hardware would need to implement only the shift register. And software would need to relocate code & data from the "safe" EPROM addresses to RAM. Downside would be that one could use only half of the EPROMs capacity.

Anyways, fully implemented hardware would be more software-friendly.

---

Hmm, no, didn't document anything with photos. It's only an IC with some wires anyways. Though, the wires do actually look a bit funny, maybe it's worth taking a photo... I was visiting my parents when making the circuit, couldn't find a normal 36pin centronics socket, and all I could get my fingers on was an old RS232 cable with 25pin dsub plug, so I had to use that one.
Title: Re: ACID chip inside
Post by: OCT on 08:20, 18 February 10
Quote from: nocash on 02:33, 18 February 10
I have no plans to implement an ACID-clone in hardware, I've never used PALs, so I'll leave that part to somebody else.
[...]
Using  PICs... aren't that software controlled microprocessors? Not too sure if that could work. The stuff must be processed at 4MHz, to implement that in software, the CPU would need to run at 100MHz or so. Dunno if modern PICs are that fast.
As Xilinx has been mentioned above (http://cpcwiki.eu/forum/index.php/topic,410.75.html#msg5533), the route to go is probably programmable logic like CPLDs or Flash-FPGAs (the approach self-taught "über-geek girl" Jeri Ellsworth used years ago already to emulate the entire C64 in a joystick that retailed for 29 dollars IIRC, a project also at the core of the C-One) which can be turned into anything from simple gate arrays to microprocessors with network interfaces (since even low-end models are much more powerful than what we need, we could give the "bored" chip real estate other things to do, e.g. so one of several EPROMs could be toggled for the next reboot as inspired by Amstrad's Cartridge Software Demonstrator (http://cpcwiki.eu/index.php/Cartridge#Demonstration_System), or the EEPROM image could even be remote-flashed via bluetooth much like a .DSK file is loaded onto an HxC floppy emulator), with much of it from libraries of code available online.
Since this particular development kit was asked for to describe your discovery, there are folks around here who seem to have much experience with it and find that more intelligible even than x86 assembly. ;)
Title: Re: ACID chip inside
Post by: spybro on 08:22, 18 February 10
great news!
really glad to hear that now we can unleash the power of our cpc+
just wanted to thank all the guys involved in this project
keep up the great work ;D ;D ;D
Title: Re: ACID chip inside
Post by: Nilquader on 10:10, 18 February 10
À microcontroller is probably too Slow to simulate the ACID, but these few Shift and XOR operations should easily fit into a xilinx 9572xl cpld (or similar). Anyone here able to weite some Lines of vhdl Code?
Title: Re: ACID chip inside
Post by: arnoldemu on 10:29, 18 February 10
Quote from: Bryce on 12:50, 17 February 10
How about "Base" or "Alkaline" ie: Neutralises Acid.

Bryce.
Simple lets call it "no$acid".
;)
Title: Re: ACID chip inside
Post by: arnoldemu on 10:34, 18 February 10
Quote from: nocash on 02:33, 18 February 10
So, and cheating around fully implementing the ACID...
I don't really want to code around having an incomplete ACID implementation so my vote goes for the full version and because you found this info, we don't need a stripped down version?

Ok, my thoughts on enhancement for cartridges now comes to a few ideas:
1. flash ram for part or alll of the rom to make it easy to reprogram. But more specifically for making game saves. If the cart works similar to the existing cpc roms, then reading a memory address could activate part of the flash ram for writing and then writing to the rom area then writes to the ram. Reading is easy of course.
Real saving on cpc+ cart? Yes please.

2. implement a bank switching method so we can go furthur than 512K, maybe by reading specific memory address ranges to switch the banks in and out? e.g. read c000 of bank 31, read c001 of bank 32 to switch in blocks of 512k ram? or if the data is sent with a write, we can perform a write at a specific memory address. it gets my vote for sure.

All depends on if the data lines are active on a write access or not.
Title: Re: ACID chip inside
Post by: arnoldemu on 10:38, 18 February 10
Quote from: nocash on 02:33, 18 February 10
Hi, updated the ACID page (with the description I had already posted here). And moved the patent info to
http://cpcwiki.eu/index.php/Programming:Unlocking_ASIC that's the stuff you sent to the CRTC index register (it has nothing to do with the ACID, the only relation is that somebody at Amstrad liked to use shift registers).
Great info. I think it is also important to add the information found on the Spanish forum, because this goes into more details of why the ACID is needed (ram access etc by ASIC).
The current info mentions how it works and a short sentence on why it is needed, but the chronograms etc from the Spanish forum are also important to see.
Title: Re: ACID chip inside
Post by: Octoate on 10:39, 18 February 10
Quote from: Nilquader on 10:10, 18 February 10
À microcontroller is probably too Slow to simulate the ACID, but these few Shift and XOR operations should easily fit into a xilinx 9572xl cpld (or similar).
Hmm, maybe the smaller version - the 9536 - is enough, too. At least it has enough pins, but I am not sure if has enough PLD cells. At Reichelt you pay 1.85 EUR (VQFP package) for such a chip, which is quite cheap (and smaller, of course ;)).

Quote from: Nilquader on 10:10, 18 February 10
Anyone here able to weite some Lines of vhdl Code?
Well, I only know the basics and so it is better if somebody who does that all day can convert it to VHDL. It's not that hard, but different from software development (e.g. timings of pin and register assignments). Anyone here :)?
Title: Re: ACID chip inside
Post by: Devilmarkus on 11:07, 18 February 10
Just a good idea to sell new t-shirts...
Title: Re: ACID chip inside
Post by: redbox on 11:47, 18 February 10
Quote from: nocash on 02:33, 18 February 10
Using  PICs... aren't that software controlled microprocessors? Not too sure if that could work. The stuff must be processed at 4MHz, to implement that in software, the CPU would need to run at 100MHz or so. Dunno if modern PICs are that fast.

The 18-pin PICs (http://www.microchip.com/ParamChartSearch/chart.aspx?branchID=1034&mid=10&lang=en&pageId=74) seem to be 32Mhz at best (but they are only is $0.97).

There is also the Ametel AVR (http://en.wikipedia.org/wiki/Atmel_AVR) type chips which I know about because the homebrew Uzebox console (http://belogic.com/uzebox/) is designed using one.
Title: Re: ACID chip inside
Post by: MacDeath on 12:00, 18 February 10
QuoteJust a good idea to sell new t-shirts...
Well, the face of Sir Sugar on an ACID cardboard perhaps ???
With a smoking pipe aside and a text like "Cracked !"... ;D


I see one of you telling there is no way to make money on Amstrad CPC scene...
Well of course, but the numerous Consoles collectionner possessing a GX4000 just because they are collectionner.

Those guys do play their console sometimes, and would perhaps buy newly made cartridges.

As a result, the "fully multi eprom" solution should be reserved to us, the scener, and finding a cheap mundane "hardwared games" cartridges solutions for all those suckers who made the GX4000/Plus range hard as hell for us to find at a decent price nowadays. >:(
(but of course, no millionnaire will emerge from this...)

Yet when you just see what Fano managed to achieve with only PLUS extra feature and the additionnal +64Ko Ram from a 6128+... using an old time well know game engine unfit for the Plus range to begin with.

Well, having the 256Ko or 512ko ROM unleashed may really give impressive results, even with no additional RAM..

I believe to that RPG games using a 6128+ and Big 512ko Cartridge and Disk drive would be awesomly sweet.


Also Demos...Music...Applications...

Of course those could be achieved with a Rom Box, but the cartridge port is a way to get easy, miniaturised and perhaps cheap Rom boxes with no extra features that nobody cares about.


The only thing : we must establish standards specifications.
Soo this may be used by everyone.


ACID : Amstrad Created Infamous Device.
Title: Re: ACID chip inside
Post by: Devilmarkus on 12:25, 18 February 10
Like this? :D
Title: Re: ACID chip inside
Post by: dragon on 12:31, 18 February 10
Yes,good idea is to build and redesign the cartridge.Adding new functions such as record items.Or others.

But that is a standard for all.

Another advantage is now that the cpcfirmware is upgradeable.

Though I suppose nobody would dare to change the roms, to put rumble feature in games.

:)
Title: Re: ACID chip inside
Post by: Devilmarkus on 12:34, 18 February 10
Because we use CPC:
(http://cpc-live.com/acidtest.png)
Title: Re: ACID chip inside
Post by: Trebmint on 12:37, 18 February 10
I know nowt about chips n stuff, and was wondering how somebody like a me a simple coder might write for cart.

Would it not be an idea to keep this almost like a publisher based thing, so anybody that wishes to publish a game has the cart produced and sold through a single place.
Title: Re: ACID chip inside
Post by: Bryce on 12:57, 18 February 10
Although I haven't seen the realtime timing of the signals yet, I can't imagine that it's not possible to implement this on a low-cost PIC running at possibly even 20Mhz. The PIC doesn't actually have to be shifting and XORing at all or doing any fancy maths, it can simply sample the input and then use a lookup table to set the outputs, this should be easily possible to do in the time required. I'll wait for all the data, before I commit to this, but if I manage to buy a CPC+ and cartridge in the mean time, I'll certainly try it.

Bryce.
Title: Re: ACID chip inside
Post by: Nilquader on 18:45, 18 February 10
Quote from: Bryce on 12:57, 18 February 10
Although I haven't seen the realtime timing of the signals yet, I can't imagine that it's not possible to implement this on a low-cost PIC running at possibly even 20Mhz.

If you look at the signal timings, you'll see that the SIN signal is updated shortly after the falling edge of CLOCK, so it's probably sampled by the ASIC at rising edge. So at 4 Mhz you only have 125ns (half clock cycle) to calculate this signal. The PIC16F84A needs 200ns to execute only one instruction (at 20Mhz) and you really need more than one instruction for a dozen of XOR and Shift operations. So a PIC is too slow, even at 40 or 50 Mhz :(

A cheap CPLD is possibly the best solution - at least it's fast enough (the small Xilinx CPLDs usually have a 15ns pin-to-pin delay).
Title: Re: ACID chip inside
Post by: Nilquader on 22:35, 18 February 10
Quote from: Octoate on 10:39, 18 February 10
Hmm, maybe the smaller version - the 9536 - is enough, too. At least it has enough pins, but I am not sure if has enough PLD cells. At Reichelt you pay 1.85 EUR (VQFP package) for such a chip, which is quite cheap (and smaller, of course ;)).
Yes, the smaller CPLD is sufficient. Just using 21 of 36 avaliable PLD cells right now....

We just need a 5V version of the XC9536, Reichelt only offers the 3.3V models.
Title: Re: ACID chip inside
Post by: Octoate on 23:26, 18 February 10
Quote from: Nilquader on 22:35, 18 February 10
Yes, the smaller CPLD is sufficient. Just using 21 of 36 avaliable PLD cells right now....
Are you already working on a VHDL implementation? If so, I will stop working on that. I just wrote the "entity" after I tried to remember what I learned years ago :).

Quote from: Nilquader on 22:35, 18 February 10
We just need a 5V version of the XC9536, Reichelt only offers the 3.3V models.
They also offer the 5V version in PLCC package ("XC 9536-15 PC44"). The 3.3V model accepts 5V on the I/O pins, so you just need a power level converter for the SIN signal. The other problem is, that the maximum voltage for the power supply of this CPLD is 4 V, but that can be provided easily, too.

P.S.: Just found a 9536 in 5 V in my component box, now I just need to find my JTAG cable... ;D
Title: Re: ACID chip inside
Post by: Nilquader on 00:08, 19 February 10
Quote from: Octoate on 23:26, 18 February 10
Are you already working on a VHDL implementation?

No - Verilog :D  The simulation already looks promising, i just need to do some more tests on the comparison values and the timing.

Quote from: Octoate on 23:26, 18 February 10
If so, I will stop working on that. I just wrote the "entity" after I tried to remember what I learned years ago :).
You don't have to. It's a great project for learning VHDL :)  But i could also send you my half-finished code if you like.

Quote from: Octoate on 23:26, 18 February 10
They also offer the 5V version in PLCC package ("XC 9536-15 PC44"). The 3.3V model accepts 5V on the I/O pins, so you just need a power level converter for the SIN signal. The other problem is, that the maximum voltage for the power supply of this CPLD is 4 V, but that can be provided easily, too.
Before adding a voltage regulator and a level shifter for the SIN signal, better take the 5V version. Almost the same price, but less parts and less space on the cartridge board.

Title: Re: ACID chip inside
Post by: MacDeath on 01:26, 19 February 10
QuoteBecause we use CPC
Then you failed Epicly... As if you passed the ACID test, you would use PLUS instead of CPC...

Your Palette don't match your pretentions. :P
(kidding and trolling, as ever)
Title: Re: ACID chip inside
Post by: Bryce on 09:24, 19 February 10
Yup, had a look at the timing last night, a (low-cost) PIC just wouldn't work  :( Pity.

Using a 3.3V part isn't a major issue if the part can handle 5V i/o. Adding an LM317 and a capacitor (which you'd probably add anyway) doesn't take up very much PCB real-estate and is a minor cost relative to the rest of the board. Of course if the i/o is 3.3v then it's a completely different matter.

Bryce.
Title: Re: ACID chip inside
Post by: nocash on 10:11, 19 February 10
Altogether I'd say that logic is better than pic, too. Anyways, with a pic, you'd of course have a full 4MHz cycle time to (pre-)calculate the next bit, not a half 4MHz cycle. Using table wouldn't be a bad idea. Sorts of like so:

read data_table(index), and increment index
mask index to 17bit range
wait for clk (via polling or interrupt)
output bit
read 9bit (oe and address lines)
compare index with old_index_table(9bit value)
if match then set index = new_index_table(9bit value)

The data_table would be fairly huge, especially if it'd need to be stored in 128Kbytes instead 128Kbits (for timing reasons), and with a 20MHz PIC, you'd have only 5 cycles to implement above stuff, which is probably impossible :-) If the processor has a parity function, you could get around the huge data_table, and would need only the 9bit tables:

parity = shiftreg and mask
do shift, and add parity
wait for clk (via polling or interrupt)
output bit
read 9bit (oe and address lines)
compare shiftreg with old_shiftreg_table(9bit value)
if match then set shiftreg = new_shiftreg_table(9bit value)

Anyways, that'd reduce only the memory needed for tables, not the 5 cycle problem.

---

With logic chips: I guess you noticed that the xor_value and cmp_values are both more a less the same. So you'd need to compute only the cmp_value, and could re-use its bits as xor_value.

And of course you won't need to deal with the calculations in the pseudo code, ie. you can simply assign them like so:
  cmp_value_bitX = pinZ
  cmp_value_bitY = NOT(pinZ)

---

For the timings. The only thing I know 100% for sure is that SIN is updated at falling edge of CLK. I've verified that myself, and it's also shown on the spanish pictures.

The other important timings would be CCLR and /CE. The pics at
  http://amstradcpc.mforos.com/305097/7723493-que-hace-exactamente-el-chip-acid-de-los-cartuchos/?pag=5
are showing only totally irrelevant signals like RAS and CAS :-) but unfortunately not CCLR and /CE.

I don't have a cpc+, so I can't check when the cpc+ does update CCLR and /CE. Could somebody else check that? Please! Like one picture showing CLK and CCLR (that, without a cartridge inserted, of course), and one picture showing CLK and /CE.

At the ACID side, I haven't checked /OE timings yet. But tested CCLR today. If I didn't do something wrong:
It seems that reset occurs only if CCLR=LOW at Falling-Edge of CLK.
That'd imply that CCLR is updated a Rising-Edge of CLK. Anyways, if somebody could confirm that would be great.

The info at
  http://groups.google.com/group/comp.sys.amstrad.8bit/browse_thread/thread/00621273fbd0f8f4
only says that CCLR is low for a "whole" CLK period, but not if that period starts on rising or falling edge :-/
Title: Re: ACID chip inside
Post by: Octoate on 10:14, 19 February 10
Quote from: Octoate
Are you already working on a VHDL implementation?
Quote from: Nilquader
No - Verilog :). The simulation already looks promising, i just need to do some more tests on the comparison values and the timing.
Hey, we are in europe - that means you have to use VHDL, that's more commonly used here ;).

Quote from: Octoate
If so, I will stop working on that. I just wrote the "entity" after I tried to remember what I learned years ago .
Quote from: Nilquader
You don't have to. It's a great project for learning VHDL   But i could also send you my half-finished code if you like.
You are right and that's a good idea, because I will receive my personal FPGA development board in two months (old product from the company where I am working). I will work on my VHDL implementation when I have some time - maybe we will find different ways and can see what timings we need for the implementation. What program do you use for timing simulation? MultiSIM?
Btw, when do you set the SIN pin? After the falling edge of the clock signal? (ok, nocash just wrote it before my posting :))

Quote from: Octoate
They also offer the 5V version in PLCC package ("XC 9536-15 PC44"). The 3.3V model accepts 5V on the I/O pins, so you just need a power level converter for the SIN signal. The other problem is, that the maximum voltage for the power supply of this CPLD is 4 V, but that can be provided easily, too.
Quote from: Nilquader
Before adding a voltage regulator and a level shifter for the SIN signal, better take the 5V version. Almost the same price, but less parts and less space on the cartridge board.
As long as we are able to get 5V types, we should use them, because that will save components on the circuit board and more space equals higher price :) - on the other hand: I don't like PLCC packages (anymore), because you always have to use a socket on the board.

@Bryce: There are a lot of 5V variants of the XC 9536. You can get them e.g. from Segor or Digikey, so that shouldn't be a problem.
Title: Re: ACID chip inside
Post by: Bryce on 10:31, 19 February 10
The PIC frequencies are a little misleading, because commands aren't processed on each clock cycle, but on every fourth clock cycle, so a PIC running at 20Mhz is actually only able to keep up with 5Mhz systems. A downside for PICs, but because I used to get them for free, I still tend to use them quite often.

Obviously a 5V part would be preferable, I just thought (from Nilquaders post) that 5V parts were difficult to source or more expensive. Although I use Reichelt myself quite often, their products are reasonably priced, but their selection is still quite limited (it's slowly getting better though).

Bryce.
Title: Re: ACID chip inside
Post by: nocash on 10:53, 19 February 10
Something else, related to cartridges... some years ago I made a tool called no$cart, that converts DSK images to cartridges (stores the BIOS/BASIC/AMSDOS and DSK image in the cartridge, the AMSDOS is patched to read from ROM instead real disk).

As far as I remember, somebody told me it worked on 6128+, but did not work on GX4000 and/or 464+ (don't remember if he tested both, but at least one didn't work). Most obvious reason would be that I forgot to remove an IN/OUT opcode that accesses the FDC - but I couldn't find any such bug. So, could there be another compatibility problem...?

In the CPC+ schematics (ASIC sheet), there's this text saying "FIT R129 FOR DISC VERS". At first glance it doesn't make too much sense to me, as the ASIC should have nothing to do with the FDC. However, the ASIC does map AMSDOS (ROM bank7, translated to cartridge bank3). So my theory would be that removing R129 does disable that feature. Can somebody test/confirm/deny that idea on real hardware?

If it's that simple, then all I'd have to do would be replace ROM bank 7 by ROM bank 83h in no$cart.
Title: Re: ACID chip inside
Post by: arnoldemu on 11:26, 19 February 10
Quote from: nocash on 10:53, 19 February 10
In the CPC+ schematics (ASIC sheet), there's this text saying "FIT R129 FOR DISC VERS". At first glance it doesn't make too much sense to me, as the ASIC should have nothing to do with the FDC. However, the ASIC does map AMSDOS (ROM bank7, translated to cartridge bank3). So my theory would be that removing R129 does disable that feature. Can somebody test/confirm/deny that idea on real hardware?

If it's that simple, then all I'd have to do would be replace ROM bank 7 by ROM bank 83h in no$cart.
I think this is very possible. I believe the ASIC uses these resistors to detect the computer "configuration", and could use them to alter how it decodes I/O for example.

Looking at the service manual the GX4000 doesn't have any of these resistors fitted, and lots of missing connections.

The 6128+ has all connected.

But I would be very interested to know the result of this too. It's not obviously documented.

Another thing to consider is that the EXP signal is used by the ASIC to decide if disc rom should be decoded as 7 or 0. (same as the option link in the DDi-1 or on the 6128 main board). The option link to control this is connected here to.

In the GX4000 this is missing. I don't know if this will be pulled high or low.

If anyone is willing to make a cart I am willing to write the code to read some of this info and display it on screen so we can at least know what the "default" states are.

Has anyone tested the basic & burning rubber cartridge on a GX4000? Hmmm thinking about it, the disc rom could still be paged as 0 ... hmm.. would the gx4000 then try to boot cpm or still show the menu? hmmm

If it shows the menu then we have not gained anything useful.

I can try this last thing on a real gx4000 and my burning rubber+basic cart.

EDIT: Official spec concerning 464+: "This variant has an integral cassette tape drive, and 64k bytes of dynamic RAM. It is supplied with a ROM cartridge containing the system firmware plus the BASIC language, disk firmware and a game, although it is not possible to select the disk firmware. " ...? but the boot menu is in the disc rom..
Title: Re: ACID chip inside
Post by: dragon on 11:53, 19 February 10
In fact, I think there's a game cartridge.That only works good in the GX4000.The no exit.

That game does not go with the cpc +
Title: Re: ACID chip inside
Post by: arnoldemu on 12:12, 19 February 10
Quote from: dragon on 11:53, 19 February 10
In fact, I think there's a game cartridge.That only works good in the GX4000.The no exit.

That game does not go with the cpc +
It does work, but you have to remove all extra roms from the back of the computer and possibly any extra hardware.

I think the init code in the cartridge is a bit broken.
Title: Re: ACID chip inside
Post by: nocash on 14:20, 19 February 10
> Another thing to consider is that the EXP signal is used by
> the ASIC to decide if disc rom should be decoded as 7 or 0.
Whoops, it goes both to the PPI input, and also affects the disk rombank number? Good to know.

> In the GX4000 this is missing. I don't know if this will be pulled high or low.
Normally there should be the pull-up resistor, or the link to GND. If both are missing, then it's neither low nor high. That could also explain compatibility problems when accessing bank 7... or bank 0... but if the entrypoint is in bank 0, isn't it? So bank 0 must must be stable.

Btw. does somebody have schematics for GX4000, CPC664, CPC6128, etc.? The schematics page,
  http://www.cpcwiki.eu/index.php/Schematics
is still a bit very incomplete.

> No exit
> I think the init code in the cartridge is a bit broken.
Yeah, it doesn't init the stack pointer. It works only if booted with SP=C000h or so - which is probably not the way how a Z80 CPU initializes it, if it does initializes SP at all (?) otherwise, if SP=0000h, then the game tries to execute RET opcodes with stack at FFFxh, with ROM enabled in that region.

I've absolutely no idea how that game can work on real hardware :-) or does the GX4000 include a boot-rom which might init SP (like that in gameboys, that display "Nintendo" before starting the ROM in the cartridge)?
Title: Re: ACID chip inside
Post by: Bryce on 14:42, 19 February 10
I should have those schematics in the same resolution as the others (CPC+), that I uploaded lately. I'll have a look at the weekend, and this time I'll remove the white space first :)

Bryce.

Edit: Hey, you're in luck, I had them here. They're on the page now. I may have more at home, will check at the weekend.
Title: Re: ACID chip inside
Post by: nocash on 15:33, 19 February 10
Thanks for the schematics! Now only GX4000, 464+ are missing. And maybe schematics for cost-reduced CPCs, if they do exist. No need to remove the white space... unless you like spending some hours on necrophile puzzling :-)
Title: Re: ACID chip inside
Post by: dragon on 15:37, 19 February 10
Hey, the service manual original(paper) can buy her:

http://www.digivideo.biz/it/elettronica/schemi/serv_man_amstrad.htm

You only have to speak Italian  :D

The manuals are in English

Anyway, the 464 and the GX4000's were coming in the 6128's that I remember.

Nocash I'm going up that I have.(6128+464+ gx4000)


done:

http://www.megaupload.com/?d=8VMG4EKC
Title: Re: ACID chip inside
Post by: Bryce on 16:21, 19 February 10
Ok, added the GX4000. The CPC464+ and CPC6128+ boards are identical so there was only ever one schematic released  (the resistors between the ASIC and the ADC decide which machine they are in plus the additional RAM (and a few extra bridges on the circuit I think).

I've also added some other monitors and cassette interfaces (everthing I could find in my archive in fact).

I don't think I've ever seen schematics for the Low-cost CPC, but the must exist somewhere?

That should keep you busy for the weekend, enjoy :)

Bryce.
Title: Re: ACID chip inside
Post by: dragon on 16:31, 19 February 10
Quotedon't think I've ever seen schematics for the Low-cost CPC, but the must exist somewhere?

I remember seeing them.But I do not remember where. : (.

Title: Re: ACID chip inside
Post by: Bryce on 16:39, 19 February 10
If the KC compact Schematics are on that page, shouldn't the Aleste schematics be there too?

Bryce.
Title: Re: ACID chip inside
Post by: dragon on 16:40, 19 February 10
Ah,I remeber the 6128 cost down with preasic is in grimware

http://www.grimware.org/lib/exe/fetch.php/documentations/hardware/amstrad.cpc/manuals/amendment.service.manual.cpc464.6128.gt65.ctm644.mp3.ct1.pdf

There are several versions.The low cost is from page 14.
Title: Re: ACID chip inside
Post by: MacDeath on 16:42, 20 February 10
(http://cpcwiki.eu/imgs/thumb/7/72/AcidTestHomeWorkplace.jpg/800px-AcidTestHomeWorkplace.jpg)

Oh wow man, are you serious ???

Computers and tobacco don't fit well, your machines must be full of dust and ashes.
Title: Re: ACID chip inside
Post by: nocash on 16:59, 20 February 10
Hi MacDeath, hmmmm, The End of the Darkness : A New Hope?
Well. Now I am feeling glorified.
Any chance you could move the text to a separate page? Would almost do that myself, but then it'd look as if I wrote/created that text, and everybody would think that I am totally mad. Okay - I am. But I'd feel better if that part is blamed on me, too.

Tried to collect info on all LK's used by Amstrad, http://cpcwiki.eu/index.php/LK_Links
As far as I remember, LK7 was Autoboot CP/M on CPC6128. Though, I couldn't find it on the new schematics. Maybe I am blind - I couldn't even find uPD765 FDC and AMSDOS ROM stuff on the 664 and 6128 schematics :-)
Bryce, did you forget some files when uploading them?

> Ah,I remeber the 6128 cost down with preasic is in grimware
> There are several versions.The low cost is from page 14.
Cost-down with pre-asic? I though the trick about the cost-down cpc is that it uses asic? The 50MB pdf collapsed my computer so I don't know much more about it yet :-)

Oh, and just added some pics/info documentation acid rev-engineering:
http://cpcwiki.eu/index.php/Test_Circuit_used_for_ACID_reverse_engineering
Title: Re: ACID chip inside
Post by: nocash on 17:08, 20 February 10
> Computers and tobacco don't fit well, your machines must be full of dust and ashes.
Hey, computers are made of electronic stuff, they can take tons of dust and ashes. Somewhat different than those EU guys trying to enforce laws against "needing to take a shower after eating in a restaurant".
Title: Re: ACID chip inside
Post by: PulkoMandy on 17:16, 20 February 10
The Pre-ASIC is called like this because it was a test at Amstrad to see if the technology could be used in a CPC-Style computer. It was done before the real ASIC, as a warm up... or at least that's what most people think :)
Title: Re: ACID chip inside
Post by: MacDeath on 20:28, 20 February 10
@Noca$h : have you seen your page ?

user:nocash ???

It's inside.


But we may put this text in discussions also.
Title: Re: ACID chip inside
Post by: PulkoMandy on 20:52, 20 February 10
Hello,
I've gathered some informations on my personal server about the ACID. I recreated the PCB of classic cartridges and the schematic in eagle and I made a small library for it with the cart connector and the ACID chip.
Feel free to use them in your own design.
I'd like if you send me changes and improvements...
http://pulkomandy.tk/projects/ReACID (http://pulkomandy.ath.cx/projects/ReACID)

Feel free to reuse the data for the wiki if you feel so. Note that I may have written wrong things :)
Title: Re: ACID chip inside
Post by: dragon on 11:59, 21 February 10
QuoteCost-down with pre-asic? I though the trick about the cost-down cpc is that it uses asic? The 50MB pdf collapsed my computer so I don't know much more about it yet :-)

Yes, but not the only difference (that I have is a cost down).

The zilog z80 processor changes to sgs z80 processor.As plus(In my cpc c 1989)

Apart from the normal memory type.The motherboard also supports the memory chips of the cpc +(In mine for example is the gap, but memory is old.)


(http://cpcrulez.free.fr/img/1/Kris_CRTC4-1.jpg)

(http://cpcrulez.free.fr/img/1/Kris_CRTC4-2.jpg)

I separate de pages from cost down(jpg).

http://www.megaupload.com/?d=XFGDT04W

QuoteHello,
I've gathered some informations on my personal server about the ACID. I recreated the PCB of classic cartridges and the schematic in eagle and I made a small library for it with the cart connector and the ACID chip.
Feel free to use them in your own design.
I'd like if you send me changes and improvements...
http://pulkomandy.ath.cx/projects/ReACID

Feel free to reuse the data for the wiki if you feel so. Note that I may have written wrong things

wow good work.The pre-soldered acid sounds good.

A a silly question.It would not be possible to use the CPLD to add a little logic.That detects the size of the eeprom.And let configured automatically the cartridge?.

And another question,it's posible add a method to savegames in cartridge?.(as zelda nes,super nes for example.)
Title: Re: ACID chip inside
Post by: MacDeath on 14:20, 21 February 10
@t Dragon :

nice picture, but a few questions :

is it a 6128 motherboard ?

what are the "empty" chip slots as seen in the 2nd picture ?

Are those suposed to house extra memory ?


Concerning the "Save able" cartridges...
Many said that it was that possible in B4 the hack of the ACID, as Cartridge port lacked the OUTput like stuff.

Yet a simple mean is to get a 464+ or 6128+ and use Cassette or Disk to do the Save stuff.

Yet on GX4000 a code systeme mauy exist but this is always shitty, and not easily possible on advanced gameplays.

The main problem is that the GX4000 lacks a proper Extension port.

If it had one, it would be quite easier to upgrade it into a pseudo Computer.

Yet a modded ACID may perhaps include extra functions and allows some kind of Save Game option ?
But such Saving option would be needed for what ?

unlocking extra characters ? a code may be used.
Saving high scores ? well...
Saving games in a complex RPG ? a computer with keyboard would be better for such game anyway.
Title: Re: ACID chip inside
Post by: fano on 14:38, 21 February 10
Quote from: dragon on 11:59, 21 February 10
A a silly question.It would not be possible to use the CPLD to add a little logic.That detects the size of the eeprom.And let configured automatically the cartridge?.
So i have another silly question about them.It is my head since i tried to understand LK usage.What is the real usage of LKs.As i understand they allow to "roll" memory but what is the goal ? avoid to send signal on unused pins on 32/64/128/256K EPROM ? Could we remove them safely and connect directly A0-->A18 eprom pins to bus ?

Quote from: dragon on 11:59, 21 February 10
And another question,it's posible add a method to savegames in cartridge?.(as zelda nes,super nes for example.)
You can use RAM with a lithium batterey but needed signals to write are not presents  :(
Title: Re: ACID chip inside
Post by: dragon on 15:33, 21 February 10
Quoteis it a 6128 motherboard ?

Yes, it is called arnold 4. (The 6128 normal motherboard is arnold  3).

Quotewhat are the "empty" chip slots as seen in the 2nd picture ?

Are those suposed to house extra memory ?

In the "empty" chips  slots you can fit an alternative memory chips for de 128k ram.Yo can remove de "old" 4164 RAM and change for other(I not remember the memory type now).


QuoteYet a modded ACID may perhaps include extra functions and allows some kind of Save Game option ?
But such Saving option would be needed for what ?

unlocking extra characters ? a code may be used.
Saving high scores ? well...
Saving games in a complex RPG ? a computer with keyboard would be better for such game anyway.

Yes,I thinking in gx4000.A high scores,and rpgs :).

The truth is that the problem is that the GX4000 has only 2 buttons.

QuoteYou can use RAM with a lithium batterey but needed signals to write are not presents  :(
.

But,maybe these write signal can be implemented in the cpld?.

I mean, the CPLD could spy on the bus.Waiting for something to tell you who has to save.


Title: Re: ACID chip inside
Post by: MacDeath on 16:38, 21 February 10
QuoteThe truth is that the problem is that the GX4000 has only 2 buttons.
"I'm not sure, TIM..."

in a 1 player game, you can easily use both joypads at the same time.

with the "nunchakus" technique.

Is such way, you off course has only 2 fire buttons (Amstrad screwed up this when putting a pseudo 2 joy with 2 buttons each...thx to superior choice of cheap and shitty components...lol), but also 2x4 direction buttons...(Joy1 and Joy2)
Totaling easily in 10 buttons.

Quite enough to have some kind of advanced gameplay based on menu-selections.
(yet a keyboard is better)

Also a Mouse may actually be achieved with the Anal port (pun!) or additionnal control device (a sort of reduced key pad...like an extra numeric pad on portable computers ...)

This may even be a way to cheat with the lack of Extension Port on GX4000.

Remember the CD loader using Joy port ? of course it was read only, yet...

Perhaps the Lightgun port is able to have a sort of output ? or the analogue ? so a mean may be found to output datas ?

Need to check this but it was just a quick idea, not sure it may be possible of course (probably not).

But on the other hand : using the sound output to produce a sound signal (captain obvious...)... and using a Tape-like recorder, then using the joyport to read it back when needed.

Would need a mundane MP3/digital recorder (any USB walkman ?) and a bit of special connectors, also some software "drivers"...

Some manipulations too.

shut off the sound on you TV by simply switch to the Sound jack-out (GX4000 offers this option if I remember well...).
Put your recording device on.
click the button to start the emiting of Sound signal/Encoded datas.

There you are.

When needing to read Datas, connect your recording/player device on a Joy/analogic port adapter...
Launch the loading phase then Play the sound file.

But definitly possible, despite a bit complicated.



Quote6128 Pre-Asic Board
Ok, so it has extra empty slots for an alternate RAM model...

But was it supposed to be in case Amstrad would get another supplier or is it possible to actually fit a 192Ko or perhaps 256Ko total RAM ?

Are those in alternative config or cumulable config ?
Title: Re: ACID chip inside
Post by: OCT on 18:13, 21 February 10
Quote from: MacDeath on 16:38, 21 February 10
This may even be a way to cheat with the lack of Extension Port on GX4000.
Remember the CD loader using Joy port ? of course it was read only, yet...
Perhaps the Lightgun port is able to have a sort of output ? or the analogue ? so a mean may be found to output datas ?
Need to check this but it was just a quick idea, not sure it may be possible of course (probably not).
But on the other hand : using the sound output to produce a sound signal (captain obvious...)... and using a Tape-like recorder, then using the joyport to read it back when needed.
Would need a mundane MP3/digital recorder (any USB walkman ?) and a bit of special connectors, also some software "drivers"...
Some manipulations too.
shut off the sound on you TV by simply switch to the Sound jack-out (GX4000 offers this option if I remember well...).
Put your recording device on.
click the button to start the emiting of Sound signal/Encoded datas.
There you are.
When needing to read Datas, connect your recording/player device on a Joy/analogic port adapter...
Launch the loading phase then Play the sound file.
But definitly possible, despite a bit complicated.
Once the ACID has found its SINful self and given the ASIC the go-ahead to unlock RAM etc., it should be ready to accept (an)other magic for happily doing whatever the remaining CPLD/FPGA chip estate (unless really used for an over-the-air flash-PROMmer) is capable of - such as writing to an(other part of the) EEPROM.

I.e. the logic being conceived by nocash, nilquader et al. would first emulate the ACID and then (keeping SIN as it is when it's through with the shift-register stuff) branch into waiting for a sequence on the address bus that should have no effect on a normal CPC or Plus but let the custom IC (or WEED chip as you preferred to call it ;)) do all further marvels we could contrive.

As to turning the GX4000 into a full-fledged CPC6128+, there was an article by German hardware hacker The Cranium in one of the last issues of French A100% (and an English or German original thereof could possibly be retrieved if anyone knows the whereabouts of this guy). On power-up it's all back to square one, playing ACID first, then waiting for new magic again...

QuoteOk, so it has extra empty slots for an alternate RAM model...

But was it supposed to be in case Amstrad would get another supplier or is it possible to actually fit a 192Ko or perhaps 256Ko total RAM ?

Are those in alternative config or cumulable config ?
That's my point in recalling the old CPC 6512 (http://cpcwiki.eu/forum/index.php/topic,556.0.html) as well as the more recent CPC4MB which hold some clues to using extra/upgraded memory banks - with the sockets fully wired (if the circuitry can power them in parallel), the extra trick is just some gate logic for the proper bank-select line.
Title: Re: ACID chip inside
Post by: dragon on 19:15, 21 February 10
QuoteOk, so it has extra empty slots for an alternate RAM model...

But was it supposed to be in case Amstrad would get another supplier or is it possible to actually fit a 192Ko or perhaps 256Ko total RAM ?

Are those in alternative config or cumulable config ?

No,I think is alternative config.About the year 88/89 Alan Sugar had many problems to buy memory chips(see the book about Alan Sugar.).They just covered it back.


Title: Re: ACID chip inside
Post by: fano on 19:33, 21 February 10
Quote from: fano on 14:38, 21 February 10What is the real usage of LKs.As i understand they allow to "roll" memory but what is the goal ? avoid to send signal on unused pins on 32/64/128/256K EPROM ? Could we remove them safely and connect directly A0-->A18 eprom pins to bus ?

Found the anwser at pulko project's page, thx :

Quote from: pulkomandyThe same PCB can be fitted with different romsize, and to avoid addressing problems on the smaller ones one have to set the "LK" jumpers properly. If the pin is an address you connect it to the related CA, else you connect it to VCC. This avoids problem as the pins are used for other purposes in smaller roms. Letting the pins connected to the address could either send wrong data to the address bus, or cause short-circuits inside the ROM.
Title: Re: ACID chip inside
Post by: PulkoMandy on 23:01, 21 February 10
As for adding write support : I do not plan to do that in the first version of the cart. However, I believe it may be possible to hack up something. It would not be useable as easily as regular ram (you'd have to write to one address and read from another for the same data). But I can't confirm it is possible until I have a real computer to test.
Title: Re: ACID chip inside
Post by: nocash on 06:52, 22 February 10
Uh, "cause short-circuits inside the ROM"? Not really, one LK pair is for the power supply on 28pin chips, another pair for /PGM (aka OE2) on 32pin chips, and the other LK pair... that one seems to be useless.

Is anybody working on real ACID clones yet? As far as I see, nobody who knows something about hardware does actually own a cpc+/gx4000. So it could take another 20 years until somebody implements it :-)

Saving game positions is probably even more far away. But it'd be nice. I wouldn't like the idea to use FRAM or battery backed SRAM - that's expensive. And, nowadays, FLASH ROMs are cheaper than EPROMs, so the "ROM" is write-able anyways. It'd be stupid to include additonal RAM.

Normal writing to the cartridge should be impossible. First, there seem to be any people here who could test if it works. And second, it's very unlikely that it does work, the address and data might be output to the cartridge, but the /CE isn't (unless the hardware is bugged for some reason). Why no /CE on write? Simply because: On the CPC, writing to RAM is possible even when ROM is enabled.

So only the trick with reading from special address would do it: First reading from a special sequence of address that tells the cartridge to write instead read on next some accesses. And then doing a write like [12345]=XX as two reads from [12345] and [123XX] or so.
Title: Re: ACID chip inside
Post by: MacDeath on 08:35, 22 February 10
You got a point.Most of Existing Amstrad PLUS are in France.
The international Amstrad SCene is scattered in Europe.

Even here in france, many 6128+ are sold at unreasonnable price, and shipping fee may be even worse.

Let's say the average price range from 30€uros to 50€uros.

On the other hand GX4000 are rarely under 50€uro because consoles collectionners are more numerous and perhaps more eager to give more money.

I even saw a guy selling a 6128+ for outrageous and unrealistic 200€uros.

Problem : some poeples ask 40€uro only for one cartridge, while other may sell a complete computer with a box of disk and perhaps a pair of cartridges, or a GX400 with 5 cartridges for the same price.

Also some sell a 6128+ with absolutly no extra stuff (no disl nor extra cartridges but the basic) for unrealistic 70€uro or more.

I managed to get 2 a decent prices because I was lucky : they didn't asked for a lot and were not fare from me so I could get them by car, and i even found on in perfect state at the public garbage...

The question is : how much would you spend for a 6128+ stranger fellows ?

I'm looking if I won't buy extra 6128 near my home (negociate better prices...) so I would bring up some to spain for our friends there.

Yet a 6128+ is not that light in weight and you know the weight is quite limited when travelling by plane.

Also, I'm not rich, yet I wouldn't make profit I'm not even sure this wouldn't cost me indeed.
Title: Re: ACID chip inside
Post by: arnoldemu on 10:56, 22 February 10
Quote from: OCT on 18:13, 21 February 10
Once the ACID has found its SINful self and given the ASIC the go-ahead to unlock RAM etc., it should be ready to accept (an)other magic for happily doing whatever the remaining CPLD/FPGA chip estate (unless really used for an over-the-air flash-PROMmer) is capable of - such as writing to an(other part of the) EEPROM.

I.e. the logic being conceived by nocash, nilquader et al. would first emulate the ACID and then (keeping SIN as it is when it's through with the shift-register stuff) branch into waiting for a sequence on the address bus that should have no effect on a normal CPC or Plus but let the custom IC (or WEED chip as you preferred to call it ;)) do all further marvels we could contrive.

As to turning the GX4000 into a full-fledged CPC6128+, there was an article by German hardware hacker The Cranium in one of the last issues of French A100% (and an English or German original thereof could possibly be retrieved if anyone knows the whereabouts of this guy). On power-up it's all back to square one, playing ACID first, then waiting for new magic again...
That's my point in recalling the old CPC 6512 (http://cpcwiki.eu/forum/index.php/topic,556.0.html) as well as the more recent CPC4MB which hold some clues to using extra/upgraded memory banks - with the sockets fully wired (if the circuitry can power them in parallel), the extra trick is just some gate logic for the proper bank-select line.
The info for converting gx4000 into cpc6128 is on my amstrad webpages.
Title: Re: ACID chip inside
Post by: PulkoMandy on 11:05, 22 February 10
Fixed the text about LKs on my page.
As for manufacturing clones, I plan to write the VHDL (if no one does it before me) and program that inside some CPLD. Of course, having a Plus at home will help testing, but I can go to the next french CPC meeting and borrow one...
Anyway, I'll design the cart even if I cannot test it. Everything will be available so anyine can build it himself then...
Title: Re: ACID chip inside
Post by: Nilquader on 11:29, 22 February 10
Quote from: PulkoMandy on 23:01, 21 February 10
As for adding write support : I do not plan to do that in the first version of the cart. However, I believe it may be possible to hack up something. It would not be useable as easily as regular ram (you'd have to write to one address and read from another for the same data). But I can't confirm it is possible until I have a real computer to test.

I've tried to add write support to cartridges a few years ago. As far as i remember, the data bus is not connected to the cartridge slot during write operations. So you cannot just use one of the address lines for write enable. I might have some logic analyzer data of the cartridge slot during write and read operations lying around somewhere...

You might be able to simulate a write access by two read accesses. First buffer the lower 8 bits of the address bus and then, during the next read access enable writing and put the buffered address on the data bus. But you still need a method to distinguish a write access from a regular read access. A similar method was used on some Atari 2600 cartridges to save games.

Title: Re: ACID chip inside
Post by: Bryce on 11:46, 22 February 10
Would it not make more sense to build a small "ACID cracker" PCB that would be installed inside behind the cartridge socket of the CPC+/GX4000, so that the cartridge only needed a ROM socket and the LKs much like an Atari XL Cartridge? This way you can have many cartridges without having to buy/program many VHDL parts?

Bryce.
Title: Re: ACID chip inside
Post by: PulkoMandy on 11:52, 22 February 10
For saving, you can enter "savemode" by connecting a special cartridge bank. If there is a CPLD in the cart it can be used to create some mapper logic like in NES games...

As for building an "acid breaker", yes, that's a possibility. You can even remove the ACID chip from your system cartridge, solder it inside the Plus and cut the sin pin from the cart port. This way you can plug either official or unofficial carts without bothering (if there is an ACID inside the cart it will be ignored).
Another possibility is to do some kind of Y-connector, plug your system cart to one side and another one without ACID on the other. This way the system cart provides the ACID and the other cart provides the rom data. Using this there is no need to alter the hardware, and no need to scavenge an ACID chip or build a new one.

But I yhkin some people will like having like-new homebrew cartridges that are easy to play without having to mess with all this : just burn a ROM, solder it, and sell your game.
Title: Re: ACID chip inside
Post by: Trebmint on 12:01, 22 February 10
So are we saying that if you want to write a game, you'll also have to be able to solder chip and boards together? I'm eager to write new games/software for the plus like I have before, but I'm no hardware person.

Hmmm unless there is a easy way for us to buy ready made carts and burn them, or something similar I can't see there being much point in doing this at all other than for completism.
Title: Re: ACID chip inside
Post by: PulkoMandy on 12:04, 22 February 10
I'm ok to do the manufacturing of carts. Anyway, if you want to make a cartridge based game, you have to program the cart. I'll start with a simple EPROM one, but I may do a flashcart easy to program with an usb port later... I'll think about it.
Title: Re: ACID chip inside
Post by: Trebmint on 12:21, 22 February 10
Quote from: PulkoMandy on 12:04, 22 February 10
I'm ok to do the manufacturing of carts. Anyway, if you want to make a cartridge based game, you have to program the cart. I'll start with a simple EPROM one, but I may do a flashcart easy to program with an usb port later... I'll think about it.
So it whats wrong with the cart format thats supported by Winape? You can't develop using this? TBH the days of me using DevKits are gone, cos its slow and boring.
Title: Re: ACID chip inside
Post by: Octoate on 12:31, 22 February 10
I just saw that there are differences between the original Pseudocode which nocash published within this thread and the Wiki article:


Wiki:
if PinCE=0 AND (ShiftReg OR 100h)=CmpVal then ShiftReg=ShiftReg XOR XorVal



Original:
if PinOE=0 AND (ShiftReg OR 100h)=CmpVal then ShiftReg=ShiftReg XOR XorVal


I would expect that OE is the correct pin. So which one is correct?
Title: Re: ACID chip inside
Post by: dragon on 12:37, 22 February 10
I think CE is the correct,because CE is the name in service manual.

QuoteI'll start with a simple EPROM one, but I may do a flashcart easy to program with an usb port later... I'll think about it.

That sound very good.More easy that eeprom.But that need suport standard image cartridge .cpr
Title: Re: ACID chip inside
Post by: Octoate on 12:57, 22 February 10
Quote from: dragon on 12:37, 22 February 10
I think CE is the correct,because CE is the name in service manual.
Ah, ok. My mistake :).
Title: Re: ACID chip inside
Post by: arnoldemu on 13:16, 22 February 10
Quote from: Trebmint on 12:21, 22 February 10
So it whats wrong with the cart format thats supported by Winape? You can't develop using this? TBH the days of me using DevKits are gone, cos its slow and boring.
Nothing is wrong and you can develop with it.
In fact I was planning to use it in the future.

The only thing is it is always best to check on real hardware using real cartridges when you're done to fix those "not emulated" issues.

Title: Re: ACID chip inside
Post by: redbox on 14:29, 22 February 10
I understand all of the excitement over cracking the ACID and all the possibilities, but surely the first goal should be simply just to make this (http://www.cpcwiki.eu/index.php/File:Cartridge-2700-023P-1-Installed.jpg) and replace the ACID chip with a different chip (such as a PIC or whatever).

Then all we need to do is get a price from somewhere to print the PCBs (we can even source some cheap plastic moulds) and a kit could be designed really easily so people can burn their own EPROMs (such as using a PC's parallel port) and make cartridges.

Then anyone who wants to make a cartridge could do it quickly and easily using a kit (even I could solder it together using my limited skills)...!  :)
Title: Re: ACID chip inside
Post by: Nilquader on 15:54, 22 February 10
Quote from: dragon on 12:37, 22 February 10
That sound very good.More easy that eeprom.But that need suport standard image cartridge .cpr
An EPROM does not support any type of file format. cpr files are just the contents of a cartridge EPROM (and some header data which is not really necessary). You just need to burn your .cpr file into an EPROM using your eprom burner's software and put it into the cartridge.
Title: Re: ACID chip inside
Post by: Octoate on 17:39, 22 February 10
Quote from: Nilquader on 15:54, 22 February 10
An EPROM does not support any type of file format. cpr files are just the contents of a cartridge EPROM (and some header data which is not really necessary). You just need to burn your .cpr file into an EPROM using your eprom burner's software and put it into the cartridge.
The .cpr files are stored in the RIFF format. TBH, I never liked that, because I had to write a converter which converted the files into RAW data to use it in my Flash-EEPROM cartridge (externally programmed). The format is described here (http://www.kjthacker.f2s.com/docs/cprdef.html). It shouldn't be a problem to develop directly in WinApe and burn it later to check it on real hardware.

Btw, for the beginning we should keep it simple! Just a cartridge which works is enough for the beginning. All those fancy features can be added later.
Title: Re: ACID chip inside
Post by: Trebmint on 20:50, 22 February 10
For injection moulding for the casing is there not a fairly serious outlay to get a mould done of several thousand pounds/euros etc. Unless somebody owns a engineering company or can get these and supply cheaply we're going to have to work as a community surely to fund it. Or is there a cheap way to do the casing?
Title: Re: ACID chip inside
Post by: PulkoMandy on 22:28, 22 February 10
Thermofolding can be used if the shape isn't too complex (taking a sheet of plastic, heating it with a hot wire and fold it when it starts melting). The other alternative is finding a box that already have the right dimensions.

Well anyway we aren't there yet :)
Title: Re: ACID chip inside
Post by: OCT on 07:44, 23 February 10
Quote from: Trebmint on 20:50, 22 February 10
For injection moulding for the casing is there not a fairly serious outlay to get a mould done of several thousand pounds/euros etc. Unless somebody owns a engineering company or can get these and supply cheaply we're going to have to work as a community surely to fund it.
...or rather just to find it, as someone in Spain (certainly a person not unknown to the entire scene there) has gone through all this effort already. Assuming no-one would dedicate as much time to an inexplicably amazing Photoshop job, we've got to consider that in Neo's words "This thing is real" and sure looks like a case of well-made injection molding:
(http://cpcrulez.free.fr/im2/CPC_GX4000-Multi_EPROM_Cartridge-1.jpg)
http://cpcrulez.free.fr/hardware_GX4000-Multi_EPROM_Cartridge.htm (http://cpcrulez.free.fr/hardware_GX4000-Multi_EPROM_Cartridge.htm)
Title: Re: ACID chip inside
Post by: deepfb on 10:02, 23 February 10
..or rather just to find it, as someone in Spain (certainly a person not unknown to the entire scene there) has gone through all this effort already

D-o-S designed and built those cartridges - almost twenty of them. He used modeling epoxy (the kind of resin marketed to craft war-hammer figures) to make the cases and the cast where they were taken from.
Title: Re: ACID chip inside
Post by: MacDeath on 12:15, 23 February 10
Yep, i suggested Epoxy resin to Fano too, being a Warhammer fan...


Advantages : it's a chemical cold reaction, while plastic molding is a heat based reaction, needing many more specialised machines to perform.

Don't know about the price, but perhaps not that much more xpensive than getting injected-plastic proffessionnal work.
The advantage is that it is achievable completely artisanally (is it a correct expression ?)

Off topic :

Warhammer models are not exactly Epoxy made.
Forge World's model are but GW's Citadel minatures are injected plastic or "white metal".

Yet Epoxy is often used by peoples who want to home-mold their own models, and by some less mass producing Miniatures companies.

I've seen a guy molding existing official Warhammer models. He took Wraith miniatures, made molds of them (many solution exist) and did transparent White Epoxy copies, so a Fantomatic effect was achieved.

A cartridge box being not as complicated as a fantasy miniature... molds may be homebrew by someone with access to adequat machines.

Milling machine.

My father actually own a little one... I will check for this.

If it is digital, this would be sweet, just need to do good blueprint of the molds.
But before molding the casing, we must know how will the printed circuit be.

Also would the programmable chip to replace ACID be a lot bigger ?

And we should keep in mind that 2 solution will have to be :

-MultiEeprom cart : for using old games and developp stuff, also Freewares.
-MonoEprom encased cartridges : because if we are to develop new games, there is no way it should be entirely free...

QuoteFor injection moulding for the casing is there not a fairly serious outlay to get a mould done of several thousand pounds/euros etc. Unless somebody owns a engineering company or can get these and supply cheaply we're going to have to work as a community surely to fund it. Or is there a cheap way to do the casing?
Well, if you use injected heated plastic, this is that expensive, but using Epoxy solution, the mold is to be simpler.
Even getting it done by micromechanic/metalworking company would not cost thouzands pounds.

Lots of such companies in my town of Valence. I should check for their prices.

But an even simpler way is to do it by  ourselves.

glue bitz and plastic plates together or midify and existing Amstrad Cartridge (as was done by spanish guy). add some solifying pastes and so on to shape it well if you want.

Then use the same solifying paste (Milliput or whatever) to do the molds.

There you are, you just put Epoxy inside and do it a lot of time until you have your production.


Concerning LK's :
Perhaps using mundane jumpers may be nice and secure ?

http://en.wikipedia.org/wiki/Jumper_%28computing%29

Probably cheaper than switchs... as I don't think peoples would change LK's config that often .
Title: Re: ACID chip inside
Post by: Bryce on 13:15, 23 February 10
These people here - http://www.pixelspast.com/homebrew/ - supply empty cartridge housings for the Atari 2600/7800, I'm not sure of the exact dimensions, but they may fit close enough to be used and if not, maybe the company would be willing to produce a CPC+ cartridge housing if enough interest was there?

Bryce.
Title: Re: ACID chip inside
Post by: redbox on 15:15, 23 February 10
Quote from: Bryce on 13:15, 23 February 10
These people here - http://www.pixelspast.com/homebrew/ - supply empty cartridge housings for the Atari 2600/7800, I'm not sure of the exact dimensions, but they may fit close enough to be used and if not, maybe the company would be willing to produce a CPC+ cartridge housing if enough interest was there?

That's exactly the type of thing we need.  Good to know some scene cousins have been through the same thing before...!  :)
Title: Re: ACID chip inside
Post by: pepax on 23:14, 25 February 10
Quote from: Bryce on 13:15, 23 February 10
These people here - http://www.pixelspast.com/homebrew/ - supply empty cartridge housings for the Atari 2600/7800, I'm not sure of the exact dimensions, but they may fit close enough to be used and if not, maybe the company would be willing to produce a CPC+ cartridge housing if enough interest was there?
Bryce.
Unfortunately, the Atari cartridges are bigger than the CPC ones.
Title: Re: ACID chip inside
Post by: Bryce on 10:20, 26 February 10
But they may still be willing to make a CPC+ cartridge if they can get enough orders?

Bryce.
Title: Re: ACID chip inside
Post by: spybro on 11:26, 26 February 10
Quote from: Bryce on 10:20, 26 February 10
But they may still be willing to make a CPC+ cartridge if they can get enough orders?

Bryce.
i was wondering whether it is possible to make
a poll in order to see what is the general interest
and in time to make an order of many?(preorder prepay)
gryzor can be the receiver of them for greece and everybody who has claimed interest can pick it from him
and in the same way for france spain uk germany(καλα ρε την αφροδιτη της μυλου) with persons from each
country
Title: Re: ACID chip inside
Post by: MacDeath on 14:36, 26 February 10
Before producing anything :

--Get a working chip solution (chip and cheap)...

--Get a design/blue print for the printed circuit.

--Then the casing is to be designed too.

Only after all this, can a production be started.


Also in my opinion, we should/could get 2 designs :

--A cartridge with external Eprom socket (and external jumpers for the LKs) : a simple multi Eprom Cartridge to burn existing abandonware games, OS and so on.

--A 2-part cartridge : part 1 with pseudo-ACID and a socket/port for part 2, with only Eprom and LKs.

a 2-part cartridge would allows to sell New games at a cheaper price, as only the 2nd part is needed then.

But the feasability would depend of the basic cost of the pseudo-Acid and the rest...

Title: Re: ACID chip inside
Post by: spybro on 15:59, 26 February 10
the cost is relevant to the demand
it is totally different to print 1 pcb than making 50
having a poll here in the wiki we can see the rate of interest

i know that you guys just started with the making of a homebrew cartridge and i wish i had
more knowledges in order to speed things up
i believe that every cpc+ user is eager to put his hands on this kind of  hardware
after all
we waited for 20 years
Title: Re: ACID chip inside
Post by: MacDeath on 19:37, 28 February 10
http://www.retrousb.com/index.php?cPath=24

wow...
Title: Re: ACID chip inside
Post by: Nilquader on 14:27, 06 March 10
Have you ever checked the supply voltage on the CPC+ Cartrdges? On my GX 4000 there is only 3.5V and that's not enough to power the (fake-ACID) Xilinx XC9500 CPLD. I could get complicated if the CPC uses 5V, and the GX4000 only 3.5. But if this is the same on the CPC+ we could use cheap 3.3V components. (ie the XC9536xl which is about 1.80 Euro)
Title: Re: ACID chip inside
Post by: nocash on 10:00, 07 March 10
That's unexpected... are you really sure it's 3.5V? I don't have a cpc+ nor gx4000, but according to the schematics, http://cpcwiki.eu/index.php/Schematics, both are clearly connected directly to 5V.

If the schematics aren't totally wrong... did you measure the correct pin? Amstrad is using different pin-numberings, 1..36 back and forth, sometimes straight ordered, and other times zig-zag ordered, and other times A1..18 and B1..18. And are you using the original power supply? No problem if you are using something else, but if it doesn't have enough amperes, then its 5V may drop to 3.5V or so.

Cu, Martin
Title: Re: ACID chip inside
Post by: nocash on 17:57, 07 March 10
Moment...! Did you just said you have a GX4000, and know something about electronics? That'd be a big step in the history of the console :-) now please say you do have an oscilloscope - do you?

The /CE timings are still totally unclear. I could probably test the /CE handling on the ACID side, but it'd be helpful to see what signals are output by the console. A photo of the oscilloscope showing /CE and CLK signals together would be great (or screenshot, if it's a modern digital scope).

Picture showing CLK and CCLR when NO cartridge inserted would be great, too.

Picture showing CLK and SIN with cartridge inserted would be nice - though that already exists, at http://amstradcpc.mforos.com/305097/7723493-que-hace-exactamente-el-chip-acid-de-los-cartuchos/?pag=5

Finally, best thing ever would be CLK and SIN and CCLR with cartridge inserted in one picture, triggered on CCLR. Though you'd sorts of need 3-inputs on the scope, plus CCLR is probably sent only once at power-up, so it may be difficult to trigger it.
Title: Re: ACID chip inside
Post by: spybro on 22:42, 04 May 10
is there anyone outhere working on any kind of prototype?it has been awfuly  quite in here. 
   
   
 
Title: Re: ACID chip inside
Post by: arnoldemu on 09:27, 05 May 10
Quote from: spybro on 22:42, 04 May 10
is there anyone outhere working on any kind of prototype?it has been awfuly  quite in here. 
   
   

nice avatar pic. Got any that say "Asic inside" in the same style?
Title: Re: ACID chip inside
Post by: spybro on 18:04, 05 May 10
the only one i could find for you is this one

(http://img696.imageshack.us/img696/1107/asic.jpg) (http://img696.imageshack.us/i/asic.jpg/)

Title: Re: ACID chip inside
Post by: Nilquader on 15:20, 27 May 10

Quote from: nocash on 17:57, 07 March 10
The /CE timings are still totally unclear. I could probably test the /CE handling on the ACID side, but it'd be helpful to see what signals are output by the console. A photo of the oscilloscope showing /CE and CLK signals together would be great (or screenshot, if it's a modern digital scope).


Picture showing CLK and CCLR when NO cartridge inserted would be great, too.


Do we really need a scope for that job? All the signals should be TTL level, so we could use a logic analyzer to watch all the relevant signals at the same time. I think the spanish people already did a lot of analyzing with and without ACID.


I already tried to write some Verilog code to simulate the ACID, but it doesn't work yet. There are still some timing issues and I had not enough time for this in the last months. I should probalby rewrite it in VHDL so that other europeans are able to read the code ;-)





Title: Re: ACID chip inside
Post by: Octoate on 15:39, 27 May 10
Quote from: Nilquader on 15:20, 27 May 10
I already tried to write some Verilog code to simulate the ACID, but it doesn't work yet. There are still some timing issues and I had not enough time for this in the last months. I should probalby rewrite it in VHDL so that other europeans are able to read the code ;-)
I finished my implementation of the ACID in VHDL some time ago, but have no time to test it and currently no logic analyzer. During implementation I also talked to our hardware department of my company which helped me a lot to prevent the mistakes of a novice :). If you are interested in my implementation of the ACID I can send it to you!
Title: Re: ACID chip inside
Post by: nocash on 19:27, 31 May 10
> Do we really need a scope for that job?
Doesn't matter what tools you are using. The problem is that most CPC+/GX4000 owners don't have any tools ar all.

The pics in the spanish forum are showing a LOT of signals, but unfortunately not the ACID signals (don't ask what they have been doing there, and why they did do it, I've no clue).

Grim mentioned that he measured the ACID signals some weeks ago - and said he'd release the results "soon" - I hope that means soon :-)

---

> If you are interested in my implementation of the ACID
Would like to see what you made of it, too!
Title: Re: ACID chip inside
Post by: MacDeath on 15:31, 03 June 10
Hi, my brother just got a microcontroller programator...
He told me that a microcontroller could most probably be programmed to emulate an ACID chip...

We are to try this, so I would need all stuff we may know on the ACID.

Has one of you done some sort of PDF compilation of all the Datas we have on it ?

From what I saw, a microcontroller runs with +5V but also can run with less, and can get a clock even superrior to 4mhz.

Yet some of them are not that expensive actually...getting the pseudo ACID at even 10€uro could be good enough for a production of MultiEeprom cartridges or even original games as GX4000collectionners may be eagier to buy those for even 50€uros or more...



The aim would be to do a breadboard prototype running an amstrad PLUS...
With the hope I won't burst a nut to one of my beloved computer...lol...


Also I would like to ask anyone :
--What kind of component would you suggest otherwise ?
--Do you have an idea of the cost for printing some cards ? I thing a big sprue with many cards on it, just needing to be cut...Perhaps asking to some universities or schools as they sometimes subcontract small productions too (as it may have a pedagogic value) ? or simply have the equipment needed.

If the Breadboard prototype works, I may need someone to design me the printed circuit.

Concerning the boxing, I will have to craft some sort of mould myself, of find suitable casings but this is the last part too as we first need to have the working complete circuit to design the case on this.

but the first step : getting za proper erzatz.
Title: Re: ACID chip inside
Post by: MacDeath on 13:39, 04 June 10
Ok..I discussed a bit with my brother.


So from now, we have 2 projects.

--Reprogrammable Cartridge.

--Joystick Adapter.


Reprogrammable Cartridge :

Would be an Amstrad PLUS cartridge with an additionnal DB9 port.
It would contain a Micro-controller and a 512K flash memory.
What we aim at :
-You plug the DB9 port on a PC : the Microcontroller is in programmable mode : you can put anything you want in the Flash/ROM...
-You plug the Card-edge on an Amstrad PLUS (GX4000) : the Microcontroller emulates the ACID and the Flash memory acts as a ROM.

Perhaps some jumpers for the LKs... yet specially designed PLUS Softwares or modified existing GX4000 ROMs may be a proper solution to avoid those...

So  our first steps will be to :
--analyse a bit more the ACID to verify stuffs.
--Programm a microcontroller to emulate an ACID properly.
--Try a breadboard prototype...and compare both components so they react the same.

Advantage of such system : No need to have an EPROM/EEPROM burner... No need for an external ROM socket.... Cool tool for would-be GX4000/PLUS ROM based softwares developpers.

A cool improovement may be to connect the DB9 to the extension port of the Amstrad while using it as ACID-ROM, but this would perhaps be an even worse nightmare to implement... Not good to access to ROM as ROM while burning it...


Joystick coverter :
Also using a Microcontroller, in a "box" with adequat plugs in and out...
This would convert mundane modern joysticks into Old fashionned  9pin ATARI standard joysticks.

The aim would be that you may put USB joys, playstations or Xbox joys.
IMO, the Plasystation joy is good as it is easy to find cheaply... and has a lot of buttons.

Of course this can get trickier than expecter, as the 9pin Atari standard was followed by manufacturers only in 1 button mode.
But it would be quite better to implement the various 2or more buttons configs.

We will also try to implement the D+6 1 player joystick for the Amstrad CPC...
This is simply the 2 Amstrad Joys merged as one, enabling 2 fire buttons and 2x4 directions (4 of them used as Fire buttons).

Will also see for Amstrad PLUS Analog joys (may be trickier...)

But the aim would be that this may enable to use modern Joys for AMIGA, Atari ST, SEGA MS or MD...ZX speccy, C64...and whatever.

Perhaps a Mouse too ?

Of course such Box would need a powersupply...



What do you think about it ? I may start a new topic for this...but it can wait.

Is anyone of you used to microcontrollers ? Do you think it may be an adequat technical solution ?

Also has anyone of you facilities for card-printing or cheap components supply ???

Are you aware of technical impractibilities concerning the use or Flash Memory for an Amstrad PLUS Cartridge ?
Experience of Amstrad ROMboards designers welcomed...


From now, we are awaiting deliveries of some components (Flash memory, Microcontroller, Breadboards...) to go further in those developpments.



Needless to say, if those projects get to a successfull end, we may manage a production and expect developpers (You my friends) to feed those with some softwares or applications.

Sweet stuffs ?
Symbos/Future OS special PLUS versions... Soundtrakers special versions... and  256K or more ROM games.

Concerning the Joy adapter, this would be great if Game developpers implement the use of a 6 button joy... or dual direction+2 button (games like Gryzor or forgotten worlds, but even wizball... Commando... may make use of this.
Enabling to move and aim diferently.
Title: Re: ACID chip inside
Post by: spybro on 08:51, 05 June 10
Really great ideas MacDeath!
Just a quick question about the cartridge
is there a way to make some extra ram through the cartridge in the cpc+?


Title: Re: ACID chip inside
Post by: Bryce on 15:10, 05 June 10
The Joystick idea sounds good and should be pretty easy to implement. The mouse adapter already exists http://www.cpcwiki.eu/index.php/PS2Mouse although it's not really true USB, it switches the USB mouse back to PS/2 mode but should be able to handle most USB mice. You should be able to map six buttons to the port in total, the CPC joystick port has fire 1 + 2, plus an undocumented 3rd input for each joystick, so all six could be mapped to a single modern USB joystick. Your biggest problem will be compatibility, because there isn't a strict protocol for USB mice, every manufacturer seems to have done their own thing. No idea about xbox / PS3 joysticks though.

The ACID project will be a little trickier, the ACID does an awful lot within one clock cycle, so the µP will probably need to be running at 100Mhz or more to react fast enough. A PAL would probably be a better solution for this.

As far as microcontrollers are concerned, I do most of my stuff with Microchip PICs, if they are the processor you're using you can send me a PM if you need any help.

Bryce.
Title: Re: ACID chip inside
Post by: fano on 15:17, 05 June 10
Quote from: MacDeath on 13:39, 04 June 10Reprogrammable Cartridge :

Would be an Amstrad PLUS cartridge with an additionnal DB9 port.
It would contain a Micro-controller and a 512K flash memory.
What we aim at :
-You plug the DB9 port on a PC : the Microcontroller is in programmable mode : you can put anything you want in the Flash/ROM...
-You plug the Card-edge on an Amstrad PLUS (GX4000) : the Microcontroller emulates the ACID and the Flash memory acts as a ROM.
I hope you'll success in that because it is a great idea.We could release easily new cartridge software for GX4000/CPC+ with this type of cartridge , this would be a great improvement for devellopers and for users !
Title: Re: ACID chip inside
Post by: MacDeath on 16:34, 05 June 10
From what we understood, the ACID has a 256 (8 bit)pool  of sequences (the codes) ?
So those may be pre-calculated and put in the internal memory of the MicroContr... not ?


100Mhz ? are you sure ? the microcontroler we aimed at was 16MHz...
But this can be not that simple...
A quite modern microcontroler can perhaps fullfill fast enough calculus and functions, and my brother wanted to programm it in assembler (not in Basic) so the beast would work at it's fullest potential.

;ACID reverse-engineered 13-16 February 2010 by nocash (Martin Korth)
;below is repeated on every CLK cycle...
CmpVal=13596h, XorVal=0c820h
if PinA0=1 then CmpVal=CmpVal XOR 0000ch, XorVal=XorVal XOR 00004h
if PinA1=1 then CmpVal=CmpVal XOR 06000h, XorVal=XorVal XOR 06000h
if PinA2=1 then CmpVal=CmpVal XOR 000c0h, XorVal=XorVal XOR 00080h
if PinA3=1 then CmpVal=CmpVal XOR 00030h, XorVal=XorVal XOR 00020h
if PinA4=1 then CmpVal=CmpVal XOR 18000h, XorVal=XorVal XOR 08000h
if PinA5=1 then CmpVal=CmpVal XOR 00003h, XorVal=XorVal XOR 00000h
if PinA6=1 then CmpVal=CmpVal XOR 00600h, XorVal=XorVal XOR 00000h
if PinA7=1 then CmpVal=CmpVal XOR 01800h, XorVal=XorVal XOR 00800h
if PinCE=0 AND (ShiftReg OR 100h)=CmpVal then ShiftReg=ShiftReg XOR XorVal
NewBit=ShiftRegBit0 XOR ShiftRegBit9 XOR ShiftRegBit12 XOR ShiftRegBit16
ShiftReg=(ShiftReg SHR 1) + (NewBit SHL 16)
Wait for falling edge on PinCLK
if PinCCLR=0 then ShiftReg=1FFFFh      ;\done at falling CLK edge
PinSIN=ShiftRegBit0                    ;/

QuoteThe 16pin ACID chip (in the cartridge) is sending a serial data stream   to the 160pin ASIC chip (in the computer). The data stream is generated   by some shift/xor logic, and is also affected by the EPROM   address/enable signals. If the data stream isn't correct, then the ASIC   does scatter access to RAM, making the cartridge unusable. 
What is the actual clocking of the serial Data stream ?

What does it look like ?



Also concerning the MicroControler, we may not take the smaller model... but one with enough functions or internal memory to storage precalculated datas and so on...
If the stuff has to enable writing on the Flash Memory, we may need this.

ATMEL brand was the kind of Microcontroler we were looking at.
The component we ordered is to be a DIL24, about the same pin number as the eeprom used in cartridges.

Needless to say this multifunction-cartridge is to be bigger than the original GX4000 cartridges.
But trying to in-build the writing function seem a good idea to me.
Better than having an Eeprom socket (would need an Eeprom burner...ouch)... this would be PC-User firendly.

Many upgrades can be done perhaps...
Just like : ability to be plugged as Extension on CPC too... like a ROM box with a 'limited) writing function then...

But before trying to handle this, we must verify that ACID can be emulated properly with it, the rest would be more trivial.

The Flash memory is like the Eprom, but with a different Pin setting (yet same PIN number) so a new board is to be designed anyway.


For the Joystick adapter, it seems that some ATMEL microcontroller do have USB ports or Analog ports... sort of.

Anyway, I'll keep you informed once we recieve the componnents...


It's cool I could manage my brother into this.

He was in Engineer school... stopped after completing the 4th year (1 last year to do) because he became a professionnal musician...lol.
In a band called Dionysos...almost famous in France.
http://en.wikipedia.org/wiki/Dionysos_%28French_band%29
http://www.dionyweb.com/site/index.php
But as Computering also remained his hobby... he has a good level of knowledge... (Both electronnic and software)
If I suck at coding, that's because it was him who operated the Amstrad CPC at home...



For the Joystick adapter :

IMO Xbox and Playstations are good choices.
My bros told me he prefered the Xbox but Playstation are also cheap easy to find (thx to the hueg sucess of PS1) and has a lot of buttons.. just hope the plugs are easy to find...
Concerning PC gamecontrollers, it may be a complete nightmare as every manufacturers do as he wishes, to many different stuff...
While consoles are perhaps more/betterly standardised.

So yeah, even if centered on Amstrad, the aim is to do it a bit universal for every common 9pin ATARI joy standard...
Sega 8/16bit, AMiga, Atari ST, Speccy, C64 and Amstrad...
1 button "Atari" is alsmot universal... 2 and more buttons are somewhat more exotic (especially on Amstrad...).

But using a microcontroller is better than what I was thinking about first (re-cabling SEGA controllers) as it opens the field for modern "shitton-buttoned" controllers...

Title: Re: ACID chip inside
Post by: fano on 16:39, 05 June 10
Quote from: spybro on 08:51, 05 June 10
Really great ideas MacDeath!
Just a quick question about the cartridge
is there a way to make some extra ram through the cartridge in the cpc+?
nope , signals needed for writing are not present on cartridge bus :/
Title: Re: ACID chip inside
Post by: MacDeath on 17:32, 05 June 10
Quotenope   , signals needed for writing are not present on cartridge bus :/
Yep, the Cartridge port on GX/PLUS range is Read only... as it was designed to only feature ROMs and the ACID.



But a RAMbox is not that complicated, just need to put it on Extension port (so unfit for a GX4000 only).

Where can I find blueprints for such devices (like a 512k extension) ? Are some of you selling "Assemble-it-yourself-kits" ?


For the first cards, we where considering this :
http://www.expresspcb.com/ExpressPCBHtm/SpecsMiniboard.htm (http://www.expresspcb.com/ExpressPCBHtm/SpecsMiniboard.htm)
"The Standard MiniBoard " would probably allow 6 cartridges printed circuits for 51$+shipping... accoeding to dimensions.

The plug card-border is 1.9 " wide...
3.8 x 2.5 inches.
3.8" = 1.9" x2...
so we can put 2 carts inside this.

A clever design is needed though.  ;)

Advantage : those cards are pre-"Holed" (pre-pierced)...

But do some of you know better suppliers for such stuff ?

  Electronic schools can perform such production, but would they ?
I will perhaps ask the Grenoble's electronic faculty...   


I know it is far too optimistic but... from what we saw approximately and roughly :

Microcontroller : 6 euros...   + shipping   
Flash Memory : 8 €uros... + shipping       
Printed circuit : 51$+shipping = 100$ for 6 cartridges...     well it was somehting like 12-14E per printedcircuit   

+ a bit of componnents (diodes, cristal= : +8 euros...?)

For the LKs, I don't know if it is that necessary ?
  as there are only 25 original GX4000 games, modding them may be better   so we just keep on 512k Lks setting... or a pair of jumpers...then...

We are at 40€uros, perhaps 50€uros...very roughly...

as :
--Shipping cost decreases with more components.
--Component's cost decrease when you buy 10...or even more...
--Some of you may have good suppliers... or circuit printing facilities...

And we still have no casing...

But I don't think it's more expensive than a modern RAMbox or ROM box, and it would not need an Eprom burner... not buying many additional Eeproms...


Concerning "original games productions", of course such re-writable cartridge" bypass every software-commercial concepts.

But perhaps some sort of "write protection" can be implemented... as the microcontroller would manage this with our specifications...
the "Re-writable" and the "Really ROM"...

So a 2-part cartridge one may be needed...
1 Cart with only the ACID and a "compatible" plug.
1 cart with only the memory and a "compatible" plug...

Of course you'ld have to get the "ACID part" first and once, so the "games part" are less expensives because 1 less component and smaller printed-cards...

The plug between ACID and ROM would be a bit more exotic.
It's to be a 28pin connector...
Perhaps a clever code-software...  or whatever so the "original game" rom would work only with the "original game" ACID/Microcontroller and not with the Re-writable one...

So yeah, you fellow CPsCeners would not be bothered (yet it's always kool to have originals and support productions...) but the Money making console collectionners dumbers that put 100+ €uros at €bay to get a "very RARE collector GX4000 burnin' rubber cartridge"...héhéhé...
would pay for us...


But too much dreams kills it.
We must first see if we can manage this ACID emulation... Hope my brother is as good as I believe...




Title: Re: ACID chip inside
Post by: Bryce on 17:53, 05 June 10
16mhz might be a little too slow, most microcontrollers are very flexible, but not very efficient. The Microchip PICs need 4 clock cycles per command, which means that at 16mhz, it's really only running at 4mhz, so a loop to say "check a pin for signal, then jump to correct value in table and send it out" would take at least 16 cycles, ie: it would have a 1mhz reaction time and still be too slow for the CPC. I know Atmel are supposedly faster, but I'm not sure of the exact timing, so you may run into problems with reaction time with them too. I also usually program them in assembler, that's normal for microcontrollers.

Still, when you have the code written, you can always choose a faster µP to get it working at the right speed.
And it sounds like an interesting project, have fun.

Bryce.
Title: Re: ACID chip inside
Post by: OCT on 21:34, 10 June 10
Quote from: MacDeath on 17:32, 05 June 10
Concerning "original games productions", of course such re-writable cartridge" bypass every software-commercial concepts.
Of course you'ld have to get the "ACID part" first and once, so the "games part" are less expensives because 1 less component and smaller printed-cards...
We must first see if we can manage this ACID emulation... Hope my brother is as good as I believe...
Your design ideas would be nicely complemented by my earlier proposal of a wirelessly remote-programmable cartridge and a rebirth of Amstrad's demonstrator (multi-cartridge menu):
http://cpcwiki.eu/forum/index.php/topic,410.msg5537.html#msg5537
http://cpcwiki.eu/forum/index.php/topic,410.msg5586.html#msg5586
Title: Re: ACID chip inside
Post by: MacDeath on 03:25, 11 June 10
Yeah but perhaps too costly...as too much expensives components needed...perhaps

We all have a PC...
Just having a simple PLUS cartridge that could be re-filled in Datas by a PC is quite good enough...
the wireless or the Menu aspect is a bit too much acctually (yet would be ideal).


My Brother admited his use of the microcontroller for this may be a "borderline".
But he thinks this can be done by precalculating stuffs...
You know, the codes the ACID give to the ASIC... those can certainly be precalculated...

So we'll see if this works.
He recieved some more components...soon we'll try to achive this.


The only way this can be well done is to permit GX4000 possessors to have new games...
We, the PLUS  computer geeks (no consolefags.. sort of...)... we can still homebrew some sort of more advanced device... After all, on a computer with Extension port, a ROM board is already doing all this...

So just if We can manage to test a working component emulated ASIC...We can then custom this as will...(we can do it also by simply cannibilising cartridges...)

But to be viable the 2 part cartridges should be supplied with a production of good games...certainly the harder part...

2 part cartridges :
1st game cost more (2 parts) but latter games don't have to feature another ACID...so quite costless... (package, casing, ROM, board and connector...).
Title: Re: ACID chip inside
Post by: fano on 08:05, 12 June 10
Quote from: MacDeath on 03:25, 11 June 10We all have a PC...
Just having a simple PLUS cartridge that could be re-filled in Datas by a PC is quite good enough...
the wireless or the Menu aspect is a bit too much acctually (yet would be ideal).
A simple cartrige able to receive a little SD card to emulate ROM is pretty suffisant.Now you spoke about , i need this  :-*
Title: Re: ACID chip inside
Post by: fano on 14:21, 12 June 10
More this would be usefull not only for pure cartridge game but we could write software to 'mount' cartridges as read-only disc...
Title: Re: ACID chip inside
Post by: MacDeath on 17:28, 13 June 10
QuoteTimings   Although the functionatlity of the ACID chip is known. The timings of   the signals coming from the computer is still unknown   (reverse-engineering was done on a ACID chip, without owning a   CPC+/GX4000). 

       
  • CLK is known to be 4MHz, and SIN is known to be updated on   falling edge of CLK, as seen on this picture (http://cpcwiki.eu/forum/../imgs/c/c2/ACID-SIN.jpg). 
  • Judging from the ACID chip, /CCLR is checked on falling edge   of CLK. However, juding from  this picture (http://cpcwiki.eu/forum/../imgs/b/b6/ACID-CCLR.png), /CCLR is changing on   falling edge of CLK. If this is true (the picture resolution isn't   perfect), then it's unclear how the ACID can interprete /CCLR in a   stable way while it's changing. Possibly, it can't do that at all (ie.   it might act unstable, and the CPC+ might need to retry sending /CCLR   several times). 

            
    • A picture showing CLK and /CCLR without ACID connected (at   better resolution) would help! 
    • A picture showing CLK and /CCLR with ACID connected would be   nice, too (trigerred on the LAST /CCLR coming from the CPC). 
  • The /CE timing is still unknown, too. The ACID might check   A0-A7 on raising or falling edge of /CE. Or, on raising or falling edge   of CLK while /CE being LOW. Or at whatever other time. 

            
    • A picture showing CLK and /CE would help! 
    • Best also showing one or more of the A0-A7 signals. 
OK, got a call from my brother.
He recieved the component (Microcntroller, Flash memories...)

But he had some questions concerning the Clk signal.

Is it the same as for the CPU from the Amstrad ?

His aim would be to synchronise the new emulated ACID with the cPU, and using some additionnal chip, overclock the 4MHz signal to 16MHz...
Then he thinks if this can be done, the rest is mostly software/programm optimisation.

As this sufggests, most of the timing part on real hardware is still not well documented...


If the spanish who did some measure can supply stuff, this may well help, folks.
Title: Re: ACID chip inside
Post by: TFM on 04:49, 18 August 10
Did somebody try to buy ACID chips? Did you get them?

Who wants to buy them? I would like to get them, but n-tronics didn't answer my email.

Any ideas?
Title: Re: ACID chip inside
Post by: dragon on 17:22, 18 August 10
mmm,You can try register there:

http://www.netcomponents.com/es/results.htm?d=1&t=f&r=1&pn1=il03p1003

or ask there
http://www.powercomponents.nl/webshop/index.aspx?a=3&artcode=IL03P1003

I think n-tronics not respond because many people ask for the acid, but nobody buy

them.must think they are kidding.

Or register here:http://www.brokerforum.com/electronic-components-search-en.jsa?originalFullPartNumber=il03p1003&x=49&y=16&hasNoSearchCriteria=false&searchPartNoLabelValue=Search+Part+Number

try register to contact directly with provider without intermidiary such as n tronic.

TFM/FS you are german right?.n- tronics is in germany,telephone  they directly.They speak german.

http://www.n-tronics.com/english/contact/contact_information.php

I can think of nothing else.

Title: Re: ACID chip inside
Post by: TFM on 01:29, 19 August 10
Well, universe is funny every now and in :o  Today I got finally a mail from them!

But... in the post before they wanted 4 Euros - now they want 7,86 Euros!!! I wrote them back that this is more than expected, that it makes no sense to buy it for that prices (final price of hardware) and if they can make me a better offer.
Thay wanted 4 Euros before, I don't pay more now. If they want that much, they can sit on them as long as they want. But for less than 4 Euros I would get a 100 of them an make the cardridges. - Which also means if somebody wants one or two of them, you would get it. However 7,86 is way to much. For 6,66 Euro I can already add a 256 KB ROM box to the CPC (but about this we talk another day).

Look... that's what they wrote...:

Vielen dank für Ihre Anfrage.
Wir freuen uns, Ihnen das nachstehende Angebot unterbreiten zu dürfen.

Artikel: IL03P1003
Gehäuse: DIP16
Date Code: 1992
RoHs Konform: nein
Menge: 100
Stückpreis: 7,86 euro
Liefertermin: 3 Tagen (kein China Waren)
Title: Re: ACID chip inside
Post by: dragon on 09:48, 19 August 10
That is the law of murphy.

Maybe that price is with shipping?
Title: Re: ACID chip inside
Post by: TFM on 19:20, 19 August 10
Quote from: dragon on 09:48, 19 August 10
That is the law of murphy.

Maybe that price is with shipping?

Yes, Murphy law, and not the fist time positive :-)) I got a better price for 100 pieces, it's still 6,85 Euros - a pain in the ass. However nobody will ever produce an ACID for a cheaper price ;-) So I ordered them.
Title: Re: ACID chip inside
Post by: jbaudrand on 12:37, 20 August 10
:_) I'm a bit confused, they still produce it? or they sold all item 'till the stock is out?

Title: Re: ACID chip inside
Post by: steve on 13:36, 20 August 10
It is no longer being made, but one company seems to have a small quantity of old stock, when this stock is gone, we will have to clone the chip which may cost more than the price asked for this old stock.
Title: Re: ACID chip inside
Post by: jbaudrand on 18:05, 20 August 10
:) thanks for explain it. hop you do amazing game with it!
Title: Re: ACID chip inside
Post by: TFM on 20:04, 20 August 10
Quote from: jbaudrand on 18:05, 20 August 10
:) thanks for explain it. hop you do amazing game with it!

I'll use them all for cartridges with FutureOS on it :-)
Title: Re: ACID chip inside
Post by: dragon on 09:53, 21 August 10
You have to take pictures of the package when arrive.For posterity.

They have already updated the database only 400 available.

Title: Re: ACID chip inside
Post by: TFM on 02:35, 23 August 10
Quote from: dragon on 09:53, 21 August 10
You have to take pictures of the package when arrive.For posterity.

They have already updated the database only 400 available.

Can't wait to get message that they have arrived :-)
Title: Re: ACID chip inside
Post by: Gryzor on 08:33, 23 August 10
It's actually amazing they didn't write that stock off ten or fifteen years ago. Can you imagine thise box sitting in a corner for all these years, properly stocked and maintained in their database? :D
Title: Re: ACID chip inside
Post by: andycadley on 10:25, 23 August 10
Quote from: Gryzor on 08:33, 23 August 10
It's actually amazing they didn't write that stock off ten or fifteen years ago. Can you imagine thise box sitting in a corner for all these years, properly stocked and maintained in their database? :D
Judging by their website, they seem to specialise in stocking and supplying out of manufacture parts. So, a box full of ACID chips is probably not the most bizarre thing they have.  :)
Title: Re: ACID chip inside
Post by: Gryzor on 06:21, 24 August 10
You're probably right about that. I'd like to take a tour of their warehouse!
Title: Re: ACID chip inside
Post by: Octoate on 01:03, 05 September 10
I think last but not least we got it...

Greeting from XzentriX 2010: Nilquader and Octoate...
Title: Re: ACID chip inside
Post by: fano on 01:11, 05 September 10
OMG they made it ! Champagne !
Title: Re: ACID chip inside
Post by: TFM on 01:48, 05 September 10
Quote from: Octoate on 01:03, 05 September 10
I think last but not least we got it...

Greeting from XzentriX 2010: Nilquader and Octoate...

Hi Octoate, can you provide some more details? (Whenever you're back from the meeting and have got some rest ;)
Title: Re: ACID chip inside
Post by: nurgle on 10:52, 05 September 10
Quote from: Octoate on 01:03, 05 September 10
I think last but not least we got it...

Greeting from XzentriX 2010: Nilquader and Octoate...

Confirmed. posting made from my Amiga on XzentriX 2010.
Title: Re: ACID chip inside
Post by: Cpcmaniaco on 17:43, 05 September 10
It's very interesting, and the cartridge of the photo is interesting too.

Tell us more, please.
Title: Re: ACID chip inside
Post by: spybro on 18:23, 05 September 10
looking forward to that
please provide some more info
GREAT WORK!
Title: Re: ACID chip inside
Post by: MacDeath on 18:53, 05 September 10
German and Hardware... a great love story isn't it ?


Well done... er... well clone !
Title: Re: ACID chip inside
Post by: norecess on 23:35, 05 September 10
Hi there,


Can you describe more the picture ? What does he really do ?


Phat 2 demo is not a ROM. You are supposed to put kind of roms on cartridge, so please, can you explain? :)


Thank you!


PS. It's awesome to see people turning around the CPC+. I'm a Plus owner (too) and very interested in such extensions!
Title: Re: ACID chip inside
Post by: arnoldemu on 09:42, 06 September 10
Quote from: Octoate on 01:03, 05 September 10
I think last but not least we got it...

Greeting from XzentriX 2010: Nilquader and Octoate...
Excellent!
Title: Re: ACID chip inside
Post by: arnoldemu on 09:42, 06 September 10
Quote from: norecess on 23:35, 05 September 10
Hi there,


Can you describe more the picture ? What does he really do ?
the cpc+ will lock up if the acid doesn't respond. So maybe your demo is being used for a soak test?
Title: Re: ACID chip inside
Post by: nurgle on 13:14, 06 September 10
Quote from: arnoldemu on 09:42, 06 September 10
the cpc+ will lock up if the acid doesn't respond. So maybe your demo is being used for a soak test?


That is exactly the case. They had the demo running for an hour with the emulated ACID IIRC.
Title: Re: ACID chip inside
Post by: Octoate on 13:20, 06 September 10
On the picture you see a standard CPC Plus cartridge and a CPLD development board with a Xilinx XC9572 CPLD. The CPLD is connected instead of an ACID. During the first day we had a closer look with a logic analyzer on the data which is send between the Plus and the ACID. Especially the CCLR pin was interesting because it was always high when we traced into it. We now know why: The Plus uses it for a reset when switching the CPC on to enter a defined state. If the communication get's wrong, the CPC set's the CCLR pin to low and tries to reset it again, but this usually didn't work in our tests.
After we got into it, we worked with my VHDL implementation and after half a day, where we had to trace some problems with the CPLD dev board, we were able to synthesize code, which was able to work for some thousand clocks (I will have to investigate into that even more - I want to get my implementation working, too :)). After all Nilquader tried his own Verilog version again and found out that he had a typo within the "compare" code and it worked. Yay :).
We then wanted to check if it is possible to run it for longer than just for the system screen. And because the ACID protection is running all the time, we used a demo :).

Btw, your pseudo code is correct and SIN has to be set on the falling edge of the clock signal.
Title: Re: ACID chip inside
Post by: nocash on 14:19, 06 September 10
Great that you got it working! Hmmmm, I thought it'd be obvious that CCLR is always high during operation :-) but yes, it's an interesting pin since it tells one when things go wrong. The thing that is confusing me is if CCLR is changed/sensed on falling or raising CLK edge... or elsewhere.

Same for the address line, I've no clue for which duration the CPC does output addresses, and when they are processed by the ACID, and if that's timed via /OE or via a mixup of /OE and CLK. Well, that part doesn't matter too much in practice, as long as it works one could do it this way or that way.
Title: Re: ACID chip inside
Post by: TFM on 18:42, 08 September 10
@Octoate: Thank's a lot for the explanation. You and Nil did an awesome job! Guys, you made history!
Title: Re: ACID chip inside
Post by: norecess on 18:49, 08 September 10
So... basically, can someone sum up all the things ? what it gives to a CPC Plus user ?
And what are your plans for the future ? (sales..?)
Title: Re: ACID chip inside
Post by: TFM on 18:53, 08 September 10
Quote from: norecess on 18:49, 08 September 10
So... basically, can someone sum up all the things ? what it gives to a CPC Plus user ?
And what are your plans for the future ? (sales..?)

Well, they are on the way to replace the ACID by using a CPLD. About sales... I think the ACID from N-tronics is still cheaper, but Octoate can tell more...
Title: Re: ACID chip inside
Post by: norecess on 19:12, 08 September 10
Talk to me as if I was your little brother : I don't know what is ACID, nor CPLD. Just keep the things simple : what does it allow?
From my comprehension, it's like ROM storage sized up to 512Kb. Am I right?
Title: Re: ACID chip inside
Post by: fano on 19:44, 08 September 10
Quote from: norecess on 19:12, 08 September 10Just keep the things simple : what does it allow ? From my comprehension, it's like ROM storage sized up to 512Kb. Am I right?
Simply to replace the original chip (ACID) used in cartrige to run Amstrad + (and maybe to extend it in the future).This chip is very rare and the picture shows a remplacement experiment with a programmable logic chip (CPLD).We (I?) expect new cartrige production from this  ;D

About 512K cartrige , it is just connections on its pcb and there is an article on the wiki that shows it.

Quote from: MacDeath on 18:53, 05 September 10Well done... er... well clone !
n1 m8 :laugh:
Title: Re: ACID chip inside
Post by: arnoldemu on 09:29, 09 September 10
Quote from: norecess on 19:12, 08 September 10
Talk to me as if I was your little brother : I don't know what is ACID, nor CPLD. Just keep the things simple : what does it allow?
From my comprehension, it's like ROM storage sized up to 512Kb. Am I right?

Ok.

ACID is a small 16-pin IC within the cartridge. It is used for a form of protection. It talks to the ASIC inside the CPC+. If the communication is not good or stops, the computer will lock up.
The supply of these is limited so making new cartridges is not so easy.

CPLD: I am not sure. I think it is a programmable IC which can be made to perform any functions you want, provided you program it with the "code" to do them.

The CPC+: It has the ASIC, it's version of the "Gate Array", "CRTC", "8255" and Memory logic PAL, it provides hardware sprites, better vertical and hardware scrolling, programmable raster interrupts, more colours, "dma" sound lists, better interrupts.

The good thing about the CPC+ is that it supports up to 512k in rom.

Why is this good? You can have 512k of rom for code, gfx, sound, and then the whole 64k ram (gx4000,464+) or 128k ram (6128+) is then free for you to use as you want. So really you have more freedom than a pure ram based program....
Title: Re: ACID chip inside
Post by: MacDeath on 10:31, 09 September 10
Also, it is to notice that getting something on PLUS using 512K rom would mean the machine up to its real potential...

One of the main problem with amstrad games : most of them were designed for cpc464 (old, not even Plus)  config actually...
(And a good part of them were even designed for ZX Spectrum 48 actually...)
So the whole game would load once or 48K only at one time... Tape being what it is, this is a serious limitation for a tile and software sprites based game.

Even well using the 6128 config (128K RAM and faster loadings...) it yet enough to achieve quite better stuff...
Just look at Orion Prime to catch my words...


So there, a 6128 PLUS mixing per exemple 512K ROM and perhaps a few more loadings from Disks... or even the normal 64K+512K is far beyound what was achieved...

Cartridge games were using only 64K RAM and 128K ROM... and some managed to be quite decent : Robocop2, Navy Seal, Magic Pinball, Pang, Plotting...
And only a few games actually used a full disk of Data (180Kx2 = 360K...) or more.
Mostly adventure games, RPG and so on...

So an action game with 512K of Data... this means lots of cinematics, musics, sprites or tiles... even sampled sounds and fast access to Datas (ROM) so shitton of additionnal stuff...
And having all the Datas on ROM, fully accessible... this means the RAM may then fully be used for software routines and optimisation, with more room than ever.

Game for 464 specs used to compress unused datas, and often uncompressed them eacxh time needed... loss of CPU ressource...
Also softwared sprites often got something in order to flip graphics (turn from left to right per example...)
Now we may just put both sprites sets (left and right version), gaining CPU time...
Or have a lot more variety in sprites... or whatever...

And a good RPG or tactical game for 6128+ mixing 512k cartridge AND Disks... would be simply Awesome too.

Only problem : would need a lot of work from the scene... ;)
a 512K ROM demo would be potentially...awesome... ::)

But of course, this doesn't mean the Amstrad is now the equal of an Amiga... ;D
We're still limited by the Z80...(64K at the same time...), the video modes (no square but blocky large pixels if "lot" of colours...and only 16 colour mode max.) and the Video display interrupt (50Hz... using 16K on the Z80 RAM)... And Hardwired sprites are not that easy to use as on a C64 or Japanese consoles.
But hey, this can only be better.


And a serie of No-ACID cartridge (a proper ROM box for PLUS using cartridge slot...) is still to be produced... for a reasonnable price too. :'(


Not that all those couldn't be done for a 464+ or 6128+ yet...
Just get a ROM box and the Basic Cartridge with ACID...
But it wasn't possible to get this on a GX4000 unless you cannibalized something...

Now we know we have some sort of unlimited supply of ACID (despite somewhat expensive...).


Also better OS and applications...




Just a question :
Did you tried this on the GX4000 we can see on the pictures ?
Title: Re: ACID chip inside
Post by: Nilquader on 11:32, 09 September 10
Quote from: MacDeath on 10:31, 09 September 10
Just a question :
Did you tried this on the GX4000 we can see on the pictures ?


We tried it on the GX4000 and on a 6128Plus.
Title: Re: ACID chip inside
Post by: ivarf on 14:59, 09 September 10
Quote from: arnoldemu on 09:29, 09 September 10
Why is this good? You can have 512k of rom for code, gfx, sound, and then the whole 64k ram (gx4000,464+) or 128k ram (6128+) is then free for you to use as you want. So really you have more freedom than a pure ram based program....
So in theory we could have one or several 512 KBs of additional firmware with optimized routines, additional routines, RSXs and software in one cartridge. Someone "only" needs to snip the best of the best from the complete CPC-library of games and utilities and adjust them to the RSX-format and document everything. 
Title: Re: ACID chip inside
Post by: TFM on 00:39, 10 September 10
Quote from: MacDeath on 10:31, 09 September 10
But of course, this doesn't mean the Amstrad is now the equal of an Amiga... ;D

No, the CPC is not an Amiga - THNKS GOD!!! The CPC is superior to the Amiga, you just have to take a closer look. For example an Amiga never can be a discless station, while a CPC can be (Apps in ROM, data on buffered RAM disc! Yeah! Good nite Amiga!).
Title: Re: ACID chip inside
Post by: norecess on 01:28, 10 September 10
Mouhahah, you made me laugh  :D


I'm also an Amiga owner and these machines are still the best machines ever. So sad I just discovered them 2 years ago... (I know, took time!).
Title: Re: ACID chip inside
Post by: mahlemiut on 12:40, 10 September 10
The X68000 is much better than the Amiga  :D
Just a damn shame Sharp never saw fit to release it outside of Japan...
Title: Re: ACID chip inside
Post by: MacDeath on 15:07, 10 September 10
Lol, a simple trolling and bwam ! the topic is now an Amiga topic...

Successfull Troll is successfull... 8)

And yeah, the 6128+ is cuter than the Amigha 500 (rounder design is full of win...)
And real men use Atari ST... Amiga is for wanky gamers... :laugh:

Post Edit : oh noes !!! I fed the troll...

Back to topic guys...


Would it be possible to have more information on the proto-card you used ? model, availability, price, specs...
And what equivalent we may find nowadays if it is a bit old ?
Also how much of the card/"Microcontroler" ressource did you actually used ?
Are there free ressources left to add stuffs ? like connecting also it to the extension port and emulate additional stuffs ?
Title: Re: ACID chip inside
Post by: norecess on 15:14, 10 September 10
Atari ST sucks big balls - sorry :)
I have an Amiga 600, which is the cutiest machine I ever had! and also one of the most extensible..
Title: Re: ACID chip inside
Post by: arnoldemu on 15:56, 10 September 10
Quote from: MacDeath on 15:07, 10 September 10
Successfull Troll is successfull... 8)
Feeding trolls hmmm... a game could be made from that...

Title: Re: ACID chip inside
Post by: norecess on 16:30, 10 September 10
But I forget to tell that of course, the CPC remains my favorite machine...  :-*
Title: Re: ACID chip inside
Post by: rexbeng on 16:37, 10 September 10
Quote from: norecess on 15:14, 10 September 10
Atari ST sucks big balls - sorry :)
I have an Amiga 600, which is the cutiest machine I ever had! and also one of the most extensible..


Amiga 600 suxxxxx!!!11


I rember a friend of mine got one and we couldn't properly play Kick Off 2 (you needed the num-pad to change team formation). >:(


So in my book Amiga 600 suxxorrrrr


rexbeng
Title: Re: ACID chip inside
Post by: norecess on 16:43, 10 September 10
Fortunately, things changed in last deceny for the A600 : with the presence of WHDLoad, you don't have any configuration problems, the game just works, loaded from HDD (no disc anymore! pfew! :)). Loading speed are so much faster, because the whole game is in memory. My A600 has 2Mb Chip-2Mb Fast RAM, a 4Gb HDD, Workbench 3.1 and the right Kickstart.. kick asses!!! :)
Title: Re: ACID chip inside
Post by: TFM on 20:20, 10 September 10
Quote from: norecess on 16:43, 10 September 10
Fortunately, things changed in last deceny for the A600 : with the presence of WHDLoad, you don't have any configuration problems, the game just works, loaded from HDD (no disc anymore! pfew! :) ). Loading speed are so much faster, because the whole game is in memory. My A600 has 2Mb Chip-2Mb Fast RAM, a 4Gb HDD, Workbench 3.1 and the right Kickstart.. kick asses!!! :)

Come on... the amiga discs are good for four weeks, then you can fire and forget them (bad format anyway). To have anything on the hard disc, nice, so it's like my labtop, but slower ;-)

And the CPU.... pfui, it doesn't even has I/O instructions. Memory mapped suxx, because it's a cause for crashes. And that 32 bit register thing... if I want to split them into 16 bit registers or 8 bit registers then I can ONLY use the LOWEST one! If I split a 16 bit register of the Z80 I can use both of the resulting 8 bit registers. Z80 is way better. And the CPC (when using it's RAM disc) is more quick than the Amiga :-) Let's test this an the next global CPC meeting!

Now, that's enough food for the trolls (must be good for the whole weekend). And I would by that game about feeding trolls!

Back to ACID, the question is who much you have to pay for the CPLD solution?
Title: Re: ACID chip inside
Post by: norecess on 20:24, 10 September 10
It's crazy you want to compare side-by-side CPC and Amiga.. that said, I won't continue polluting this thread anymore ;D


So... let's get back to ACID :)
Title: Re: ACID chip inside
Post by: TFM on 20:29, 10 September 10
Quote from: norecess on 20:24, 10 September 10
It's crazy you want to compare side-by-side CPC and Amiga.. that said, I won't continue polluting this thread anymore ;D


So... let's get back to ACID :)

Good idea! But... you can compare technical specs and you can compare reality! (That's more ofter quite differen!). In reality I can beat every other system (but the NC100-200) with a CPC (plus ROM board, plus buffered Exp.RAM) in some disciplines. Writing a letter is one example. But you're right, back to LSD.... eh... ACID!
Title: Re: ACID chip inside
Post by: norecess on 20:33, 10 September 10
Word Processing better on CPC ? Come on...
http://4.bp.blogspot.com/_9rv9tNJgLmI/Se2WFuvGsgI/AAAAAAAAABY/JO8nAy6CuwE/s400/Dissertation_in_Final_Writer.gif

(A600 - 68000 required)


ACIIID!
Title: Re: ACID chip inside
Post by: TFM on 20:41, 10 September 10
Quote from: norecess on 20:33, 10 September 10
Word Processing better on CPC ? Come on...
http://4.bp.blogspot.com/_9rv9tNJgLmI/Se2WFuvGsgI/AAAAAAAAABY/JO8nAy6CuwE/s400/Dissertation_in_Final_Writer.gif (http://4.bp.blogspot.com/_9rv9tNJgLmI/Se2WFuvGsgI/AAAAAAAAABY/JO8nAy6CuwE/s400/Dissertation_in_Final_Writer.gif)

(A600 - 68000 required)


ACIIID!

Not better :-) Faster! Switch your CPC on, type !P, type in your lines, print them out, save letter on RAM disc C, switch off the CPC. ... And all other machines are still booting :-)

EDIT: Impressive pic btw!
Title: Re: ACID chip inside
Post by: Octoate on 20:46, 10 September 10
Quote from: TFM/FS on 20:20, 10 September 10
Back to ACID, the question is who much you have to pay for the CPLD solution?
That depends on the distributor, but the price ranges are usually 4,50 EUR to 9 EUR when using a 5V XC9536. If it is possible to use a 3.3V type you can lower that price to 1.60 EUR. The design needs approx. 80% of the XC9536, so there isn't much left.

@nocash: I am not sure when the address lines are set (CCLR and SIN were more interesting), but maybe Nilquader can have a look at his records and tell us more. The CCLR signal is usually set to low between the rising and the falling edge of the CLK signal.

@Administrators: Please split this topic and create a new thread for the Amiga / CPC battle :).
Title: Re: ACID chip inside
Post by: TFM on 22:05, 10 September 10
Quote from: Octoate on 20:46, 10 September 10
@Administrators: Please split this topic and create a new thread for the Amiga / CPC battle :) .

Battle? A CPC can't loose in the CPC forum :-) Oh, yes, let's get offtopic again... well, so the CPLD solution can be a bit cheaper than to buy the original ACID chip. On the other hand. The real ACIDs are nearly constant in their number, some of them will die, but they will be definitely not produced any more. So I see future in the cpld replacement - and I'm lucky to own a bunch of the real ACIDs.

Now back to the topic... The CPC is the greatest system ever been built!
Title: Re: ACID chip inside
Post by: MacDeath on 12:01, 11 September 10
Are those CPLD surface mounted components ? if so this can be a little problematic as they may need a socket for traditionnal soldering, or surface mounted soldering, which may be more expensive.

getting a 5V version is perhaps better because this means we don't have to add components for the tension/Voltage.

80% used ? ok I suppose this let no room for additionnal stuffs... and whatever a cartridge port only cannot really enable real interaction I suppose.


So, a CPLD cartridge would of course need a properly programmed CPLD, perhaps a socket if surface-mounted components...
a pice of ROM (flash, is it good ?) But a way to re-write the ROM is surely needed unless you aim a full production of original games...


All those on a board.so perhaps easily more than 20 €uros per cartridge, those still having no box.

Does any of you have good electronic supplier or can manage a production ?


Also :
QuoteFeeding trolls hmmm... a game could be made from that...
Pehaps porting this from DS to Amstrad PLUS... on "NoAcid" cartridges then..

TFM/FS = Troll For Men / Food Supplier  ;D
Title: Re: ACID chip inside
Post by: TFM on 00:38, 12 September 10
Can't see them starving...

Who is interrested in producing (or buying) cardridge boards. They're small, so they can't be that expensive.

Well, I need 100 of them, so we will get a good price! Who elso wants to order them / or build them by himself?
Title: Re: ACID chip inside
Post by: steve on 02:43, 12 September 10
I would be interested in buying a couple to start with, and more later.
Title: Re: ACID chip inside
Post by: MacDeath on 02:43, 12 September 10
Well, if the whole scene is good... it is far easy to get 30 pieces actually solds... if only those are especially designed for a multi-Rom stuff...

So perhaps an additionnal connector to re-write (if Flash ROM)... or a ROM socket ?

I would be interested but before starting a real production, the card must be well designed... a real ROM box, not simply cartridges, first...
Proper Carteidges... those should be to make money on Console collectors, so new games to run on GX4000... with plastic shell and so on...


But yeah, a pair of ACID would be fine for me just to be sure I woudl be self sufficient with no cannibalizings...
Title: Re: ACID chip inside
Post by: steve on 02:46, 12 September 10
It has to be a cartridge to fit in the cartridge slot, however, a rombox with a writeable cartridge slot and rom programming capability is a good idea.
Title: Re: ACID chip inside
Post by: TFM on 03:32, 12 September 10
Ok, we should clearly seperate this:

1. A circuit board, exactly like in existing cartridges, using up to 512 KB EPROM.

2. A kind of expansion board, descripted by MacDeath.

The latter must first be designed, the former is just a 1:1 copy of a usual cartridge.


Now let me start with the 1:1 copy of a normal cartridge: I will order 100 of them, if you need them also please tell me, so we can order a bigger number, this makes it cheaper.

Title: Re: ACID chip inside
Post by: steve on 05:04, 12 September 10
Whoever is working on the acid replacement, could you tell us if it will be pin compatible with the real acid chip so it will fit on these PCBs that TFM/FS is producing?
Title: Re: ACID chip inside
Post by: Nilquader on 09:46, 12 September 10
Quote from: steve on 05:04, 12 September 10
Whoever is working on the acid replacement, could you tell us if it will be pin compatible with the real acid chip so it will fit on these PCBs that TFM/FS is producing?


No, they will not be pin compatible - the CPLD used to replace the acid is only available in PLCC or VQPF (both are SMD) packages. And they won't fit on the PCB that TFM is producing for the real ACID, unless he adds additional solder pads to assemble either the real ACID or the CPLD.


And we should use a Flash EPROM instead of a traditional UV-eraseable EPROM. Or at least add an additional LK to allow both EPROM variants.
Title: Re: ACID chip inside
Post by: nurgle on 20:59, 12 September 10
Quote from: Nilquader on 09:46, 12 September 10
And we should use a Flash EPROM instead of a traditional UV-eraseable EPROM. Or at least add an additional LK to allow both EPROM variants.


A flash cartridge like the ones available for Gameboy, etc. would be nice. Add a connector and a USB cable so the cartrdige can be reflashed from a PC. The programmer hardware can be in the cable to keep the cost of the cartridges down.


Btw.: I want a plus now.  :'(
Title: Re: ACID chip inside
Post by: redbox on 22:37, 12 September 10
Quote from: nurgle on 20:59, 12 September 10
A flash cartridge like the ones available for Gameboy, etc. would be nice. Add a connector and a USB cable so the cartrdige can be reflashed from a PC. The programmer hardware can be in the cable to keep the cost of the cartridges down.

I would definitely buy one of these...
Title: Re: ACID chip inside
Post by: MacDeath on 00:15, 13 September 10
The main problem have already been discussed...

We need from 2 to 3 different models actually...

--New old fashionned cartridges : the same as old cartridge, perhaps to release "original games" or apllications.
Such one could use existing ACID (a stock seems to be still available) but may also be based on pre-programmed CPLDs...therefore being designed differently.

--Multiple ROM cartridges or 2 pieces cartridges : on part include ACID (or CPLD) the other would be like a socket or a slot for a new cartridge format, including only the Flash/ROM... this would be great to release new games or anything "original" and actually to sell...
I would like this solution, perhaps more development cost, but once you have the ACID the other cartridges (programs) may be less expensive...
Mostly if we plan to really produce stuffs and GX4000 compatible stuffs IMO.

--Reprogrammable Rom box : would need a way to reprogram the memory... a plug to connect to a USB /PC or a plug to connect to the extension port of the Amstrad then...


Concerning the ROM we would use, Flash seems quite nteresting, isn't it ? perhaps easier to "burn", and also easier to find...
Title: Re: ACID chip inside
Post by: nocash on 02:16, 13 September 10
Yes, flash rom is fine, no question. Easier to erase (no UV light), easier to burn (no 12V voltage needed), and nowadays, it's also cheaper than eproms.

USB... would be nice for people who want to program cartridges from PC. But it's overcomplicated hardware-wise; the CPLD is a logic chip, not a microprocessor, so there's no way to implement the USB protocol on it. It'd make more sense to me if the CPC could write to the flash rom - that way one could both store games and game-positions on it.

> Multiple ROM cartridges or 2 pieces cartridges
I would doubt that that 2-pieces solution could be become a standard. Neither if you want to buy/sell games, nor if you want a rewrite-able cartridge. Can't imagine anybody really wants hardware in two pieces. Asides, that solution isn't new, one could have used it back in 1990: Building an adaptor that allows to connect two cartridges (an official cartridge with its ROM disabled, and a nonstandard cartridge with plain ROM in it). I am sure many people did build such hardware at home, but it's rather clumsy and thus never became a standard.

> Reprogrammable Rom box
You mean like the ROM boxes that connect expansion rom to the expansion port?
ROM boxes do already exist (maybe no reprogrammable flash-ones), but anyways, they don't have anything to do with ACID chips.
Title: Re: ACID chip inside
Post by: nocash on 16:22, 13 September 10
PS. just figured out that it'd be a bit problematic to boot a cpc+ with only a blank cartridge inserted, so the cpc+ could program blank carts only if it boots from expansion rom. Anyways, for saving game positions it would be nice to be able to write to the flash memory via the cartridge connector.

To program carts directly from a PC one would probably need a separate programmer (like nurgle suggested). If the carts are write-able through the cartridge connector then somebody could build such a device at later time (and for now, there would be need to recurse additional programming hardware in the cartridge design).
Title: Re: ACID chip inside
Post by: Nilquader on 18:17, 13 September 10
[/size]
Quote--New old fashionned cartridges :

We don't have to make two separate layouts here. There is enough space on the cartridge board to include CPLD and ACID mounting options on the same board layout. At least if we use SMD components whenever possible (which we should use, because they are cheaper, less space-consuming and easier to find).


Quote--Multiple ROM cartridges or 2 pieces cartridges :

I don't like that idea. I remember these SUPER NES/Super Famicon adapter boards to circumvent the region lockout. Instead of having one point of failure (the socket), we will have three. That means much more blowing into connectors. The CPLD acid will probably cost just about 2-3 Euros, so you need to buy lots of ACID-less cartridges before the adaptor board pays off.


Quote from: nocashjust figured out that it'd be a bit problematic to boot a cpc+ with only a blank cartridge inserted, so the cpc+ could program blank carts only if it boots from expansion rom. Anyways, for saving game positions it would be nice to be able to write to the flash memory via the cartridge connector.

That's not the only problem. The logic needed to program a cartridge via cartridge slot is not that trivial, because the Plus only allows read transfers to the slot. So a logic circuit inside the cartridge would need to translate two read transfers into one write transfer. So an external programmer (via CPC printer port and/or USB) is probably the best solution.
Title: Re: ACID chip inside
Post by: nocash on 21:12, 13 September 10
> the Plus only allows read transfers to the slot. So a logic
> circuit inside the cartridge would need to translate two
> read transfers into one write transfer.

Yup, I know. But it'd be the only way to store game positions in the cartridge. Some months ago 1-2 people here mentioned that they'd like that feature. Though, on the other hand, I don't really like the idea to implement it in emulators, it'd pretty much slow down the emulation speed to watch memory reads. So, the REAL problem is that there is no /IORQ on the cartridge bus, what a crap! :-)

Well, if the writes are invoked by reads from the last cartridge bank, emulators could activate the "slower" emulation mode in that situation, and still run at full speed when using normal memory banks. As far as I know, the existing carts use only 16 out of 32 banks. So it'd be nice to define a standard how to use the upper banks; I'd recommend to use only 31 banks for reading, and using the last bank to invoke write operations. Maybe some bits/addresses reserved for other things, like bank switching for bigger carts.

It shouldn't be too difficult to implement. But it would be best to have it defined now - before we end up with a terrible mess with different methods that are incompatible with each other.
Title: Re: ACID chip inside
Post by: Nilquader on 21:37, 13 September 10
Quote from: nocash on 21:12, 13 September 10
It shouldn't be too difficult to implement. But it would be best to have it defined now - before we end up with a terrible mess with different methods that are incompatible with each other.


It's not difficult, but you might need a bigger CPLD to implement such a writing scheme. You need about 33 additional I/O lines on the CPLD (if I counted correctly:
Spoiler: ShowHide
data bus in/out(16)+upper 5 address lines to detect access of last bank+first 8 address lines to transfer a data byte+WE+CE in/out(2)=33
) to implement this one. So a 44 PIN chip wouldn't work anymore. And the 84 pin version of the XC9572 is even more expensive.



Title: Re: ACID chip inside
Post by: MacDeath on 07:35, 14 September 10
There may perhaps be a solution to have some kind of saves on GX4000...
Tapes.


You emit Datas in Audio thx to sound output (ouch,) and put them on any sound recording device...
Then you use a Codemaster-CD like device...  reading your datas thx to Joy port. :P

But can the AY psg generate such signal ?


Yeah, It's a bit messy, lol...
Title: Re: ACID chip inside
Post by: arnoldemu on 09:55, 14 September 10
Quote from: redbox on 22:37, 12 September 10
I would definitely buy one of these...
me too. I would definitely buy one of these.
Title: Re: ACID chip inside
Post by: arnoldemu on 10:05, 14 September 10
Quote from: MacDeath on 07:35, 14 September 10
There may perhaps be a solution to have some kind of saves on GX4000...
Tapes.


You emit Datas in Audio thx to sound output (ouch,) and put them on any sound recording device...
Then you use a Codemaster-CD like device...  reading your datas thx to Joy port. :P

But can the AY psg generate such signal ?


Yeah, It's a bit messy, lol...

An adaptor that sits on the joystick port and can read/write data would be fantastic (like a memory stick), however, this will not work on cpc+ or gx4000 I think.

Yes, the cartridge port not having write or similar is a problem.

on 464+ or 6128+, having extra hardware on the back for load/save is a good idea and keep it seperate to the cartridge hardware.

would it be possible to connect some device that watched the common signals on the joystick port. Send out a pre-programmed stream to trigger some hardware on the port to enable and accept data?

A crazy idea but may be a good idea as an alternative to a modified cart?

Title: Re: ACID chip inside
Post by: nocash on 15:08, 14 September 10
Uh, tapes? The idea would work, so far it's a clever idea, but even if it were a zx81, I wouldn't feel comfortable with using tapes anymore. An external memory stick on joystick could work too, downside is that it requires more hardware, may conflict with joysticks, and if there is write-able flash memory in the cartridge, why not using that?

> You need about 33 additional I/O lines on the CPLD (if I counted correctly:
Good point, it'd require more pins. But not 33, let me try counting.

> data bus in/out(16)
You can't write data to data-in, so you need only data-out (=8)

> first 8 address lines to transfer a data byte
Well that are already used by the CPLD, so no need for more pins (=0)

> upper 5 address lines to detect access of last bank
If you run short of pins, you could have them ANDed externally, so you could get around with 1 pin (=1 or 5)

> +WE+CE in/out(2)=33
CE-in is already there, so you need only /WE-out and /CE-out; or maybe better /OE-out (=2).

That'd be between 11 and 15 additional pins. The normal ACID has 14 unique pins, so it should be possible to "squeeze" the extra pins into a 44pin cpld. You could even spare some pins for jumpers or links, allowing to mark portions of the cartridge as read-only, for write protecting the game-area, and leaving some K bytes write-able for game positions and hiscores.

And an address line for bank switching may be useful:
If upper 6 address bits = 111111 then latch a0-a7 as data, and make treat next access as write-acess
If upper 6 address bits = 111110 then latch a0-a7 as bank number
that'd expand the possible size from 512K to 256*512K. But would require some MORE pins to output the bank number.

Uh, not sure if that are useful ideas, or if they suggestions to create a great mess :-) does any of it make sense?
Title: Re: ACID chip inside
Post by: nurgle on 15:42, 14 September 10
All those ideas of using different CPC ports sound like a big kludge to me. Why would you want to burn cartridges on the CPC anyway, when you have to get the ROM image from the net with a PC? Sure it's geeky to put them on a 3" floppy before burning on the CPC, but I still prefer the idea of a PC programmer as a more practical approach. Its also the only way on a GX4000. It has been done for other systems, i.e.


http://blog.thewombat.org/2009/11/tototek-snes-flash-cart-review.html


It just boils down to the question how the programmer can be made very cheap. As cheap as the simplest DIY PIC programmers would be nice. Is this possible with a flash ROM inside the cartridge?
Title: Re: ACID chip inside
Post by: TFM on 21:28, 14 September 10
Well. I'm thinking of having a CPC Plus that reads the content of it's cartridge and saves it to disc. Then you can reload the content to an Flash EPROM.

The only thing you need to perform this tasks is a ROM expansion, which also provides the Lower ROM. A kind of lower ROM-RAM-Box ;-)

And NOBODY would be forced to use a PC. Well, you must not agree. That's just FutureSoft philosophy - do everything with a real CPC.

Title: Re: ACID chip inside
Post by: steve on 22:01, 14 September 10
I would also like to write to cartridges on a real CPC/+ even if it requires a separate cartridge slot attached to the expansion bus.
Title: Re: ACID chip inside
Post by: MacDeath on 22:22, 14 September 10
Quoteon 464+ or 6128+, having extra hardware on the back for load/save is a good idea and keep it seperate to the cartridge hardware.
On 464+/6128+... you havce an easy way to save/store Datas... this is called Disk Drive or Tape Drive...
You just need to make sure your program (Game or Application) include the "drivers" neded to use such device... of course it won't work on GX4000 but 8bit console guys are known to not play real RPGs... and, well... the scenne prefers Comuters to consoles, or else it can't be real scene because scene imply...computering a bit...not only playing ?


Concerning my pseudo tape solution : it is a pure fantasy and not practical at all, yet it can be a way to achieve this in theory.


But lets put this simplier :

=Complex games needing writing Datas : use a damn computer... Disk can even allows Data Disks (extension of the game, new adventures, additionnal levels, new level fdesign, extra stuff and so on...)

=Simple arcade games : ok, you can use a console, and if you cannot save your Highscore, well... who cares ?

After all, a proper easy way to write cartridge is more a computer stuff, mostly for program designers...

Console guy are only... gamers, final users... they just buy games and play them...they don't need to write their Cartridges...

And if getting a few re-writable cartridge is of wourse very interestiing (better than disks...actually...) just to be sure you get a handfull of self-designed ROMs... the rest is to be properly bought just to support the active scene and to tell "look I have an original and legal copy..."


If ACID can be replaced by quite cheap preprogrammed CPLD components, and be directly soldered on the cartridgeboards, for a reasonnable price... let's go for it...

If you want to reprogram your ROM with your CPC, just get a special Extension (perhaps using print port too...) with all the adequat components and plugs, and an adequat Software too then (on a cartridge too, lol...)
Yet this may need another plug on the cartridge...
Title: Re: ACID chip inside
Post by: pepax on 08:36, 16 September 10
Quote from: arnoldemu on 10:05, 14 September 10
An adaptor that sits on the joystick port and can read/write data would be fantastic (like a memory stick), however, this will not work on cpc+ or gx4000 I think.

Yes, the cartridge port not having write or similar is a problem.

on 464+ or 6128+, having extra hardware on the back for load/save is a good idea and keep it seperate to the cartridge hardware.

would it be possible to connect some device that watched the common signals on the joystick port. Send out a pre-programmed stream to trigger some hardware on the port to enable and accept data?

A crazy idea but may be a good idea as an alternative to a modified cart?
Something like the Atarivox? http://www.richard.hutchinson.dsl.pipex.com/ (http://www.richard.hutchinson.dsl.pipex.com/)
The old Vecvox: http://www.richard.hutchinson.dsl.pipex.com/new_page_2.htm (http://www.richard.hutchinson.dsl.pipex.com/new_page_2.htm)
Title: Re: ACID chip inside
Post by: MacDeath on 09:01, 16 September 10
On PLUS I was told the Joystick port cannot emit stuffs as on CPC old (because the double joiy port include diodes...)...
this can be an issue... if it is true.

The GX4000 seems to have almost no emiting port/plug, except the video and sound plugs...
So the idea to use any audio MP3 device (Ipod and so on) and get a Joy input/jack audio output is the only evident way.

Like the unreleased Codemaster CD-ROM loader as I told.

But this would need a special Jack/Joy kit and implement stuff on the software (ROM) to manage this.

Manipulation :

recording Datas ? connect your record-input Ipod plug on the Sound jack plug of the GX... shut the monitor sound (or else you're gonna get earsbleeding...)...
Put ipod on record, click a key (to start emiting).

Ok, now you have your save.
Name it properly (if your Walkman/pod allows this) and keep track of it.

To re-load it, connect your Ipod sound output on the "Codemaster CD-ROM loader" joystick plug.
click for starting recieving (on GX) then play the "tune"... there you are.

Not simple actually but efficient, yet only usefull for GX4000 users...lol...
Also, the routine to code Datas into sound signal with the AY may be quite... is to be developed...

464+ have a proper Tape, 6128+ have a proper DiskDrive...

And games supporting those would need to actually include "drivers" for Tape (464+), Disk (6128+) and "Codemaster gasfactory" (GX4000)
in addtion GX4000 should get the proper additional equipment :
=Ipod/MP3 walkman (easy...) able to record (using a Mic jack plug)
=minijack cable (to record)
=custom JackJoy stuff, probably needing a few Electronical components actually...

Those additional "drivers" may take a bit of bytes on the ROM... but not that much i suppose.
This is the price to pay to get a fully PLUS range compatibility for a cartridge of a game who need to save/load datas.


Of course (I don't know what Pods models have nowadays) if your pod can get bot microphone plug and sound output plug...you can get both pluged at the same time on your GX... and this also means you have quite a good amount of Data storage as most modern numeric walkman have more than 1Giga of storage.
but hey, this may be quite long to read those...


Ouch.

Well, would be fun but not that practical. :'(


But perhaps the Analog port or Lightgun port can actually emit something ?
This would simplify a lot of stuff perhaps (or not...)
Title: Re: ACID chip inside
Post by: nocash on 15:30, 16 September 10
Okay, here are the BEST possible solutions for game positions on the GX4000.

1. Unplug your joystick, wire some external logic to the joystick port (works, the select line can be used as output), connect a cassette recorder to it, connect batteries or power supply, find the correct cassette, rewind tape, press play or play+rec, and there you go, and thereafter reconnect the joystick to continue playing. That's how one would have done it in 1980. As far as I understood, that's currently favored by most people? Really?

2. Use passwords, like the secret landscape codes used in Sentinel. Nobody really likes that solution. But it has some advantages: No external hardware needed (no external power supply, no batteries, no adaptors, cables, cassettes, drive belts). And passwords could be also used on 464+ and 6128+. So it'd be a bit more realistic than the "use the built-in disc/tape drive" solution; which I don't think that too many programmers would be able to support them, not to mention to test both tape and disc on real hardware, and not to mention to support things like 80-track disc formats.

3. Allow to store data in the cartridge. Would work on all models, no matter if it's a gx4000 or 464+/6128+, no external hardware needed, and it's faster than tapes, discs or passwords. If you look at other ROM cartridge systems (NES, SNES, Gameboy, NDS, etc), you'll see that many cartridges contain battery-backed SRAM, or newer EEPROM/FLASH chips - additionally to the ROM chip. That usually costs quite some money, but if we do have a write-able "ROM" chip, then we could get that feature for free - as long as writing is implemented in the CPLD.

---

> Why would you want to burn cartridges on the CPC anyway, when
> you have to get the ROM image from the net with a PC?
I didn't mean you MUST use the CPC to burn cartridges. But if the cartridge does have the cart-edge connector for reading, then why don't use the same connector for writing? Doesn't matter if you connect it to a PC or CPC or other computer. It'd be just cheaper than using two connectors, one for reading, and one for writing.

NB. I can't picture how any such second connector should look like! I guess serial-data won't work, unless the CPLD can translate the serial data to parallel address/data lines, which would require a couple of pins. The other option would be a parallel connector, using a 40pin IDE-harddisk-style connector or so, is that how it should look like? Or, if there is no write-support at all, one could use a screwdrive to remove the chip from the cartridge, and program it with a normal EPROM burner, would be fine, unless one wants to rewrite the cartridge more frequently, like when testing self-made programs.
Title: Re: ACID chip inside
Post by: Bryce on 13:35, 17 September 10
If all the required signals are available on the ROM cartridge port, then using this port is obviously the easiest and fastest option. To reduce the cost some more, you could keep the game on a standard ROM and save the data on a low-cost serial ROM. They come in 8-pin packages, cost very little and the game can still be read-only to avoid accidental over-writing or other issues. If it's standard in all "new" cartridges, with a standard "writable address", then a standard save/retrieve sub-routine could even be written to make things easier for the programmer too.

Here's a typical serial ROM that should be viable (0.21€):

http://www.reichelt.de/?ACTION=3;GROUP=A321;GROUPID=4510;ARTICLE=40061;SID=22o5FEbtS4ARYAAGCkTJo9114e4233d9a021f88a3626f5cf64d6a

Bryce.
Title: Re: ACID chip inside
Post by: MacDeath on 17:04, 17 September 10
But I believed the cartridge port of the PLUS does not allow "write" ???
Title: Re: ACID chip inside
Post by: nocash on 19:44, 17 September 10
There is no /WR (write signal), and the 8bit databus is read-only. But the addressbus is write-able.
So one can mis-use the address bits for writing data. The same method is used in Atari 2600 cartridges, for example.
Title: Re: ACID chip inside
Post by: TFM on 20:02, 17 September 10
Quote from: nocash on 19:44, 17 September 10
There is no /WR (write signal), and the 8bit databus is read-only. But the addressbus is write-able.
So one can mis-use the address bits for writing data. The same method is used in Atari 2600 cartridges, for example.

Guess it's cheaper to just add an EPROM box or similar. Not everything that can be done must be done  ;)

That write-data trick is an excellent idea anyway  :)
Title: Re: ACID chip inside
Post by: nocash on 21:28, 17 September 10
How cheaper? Flash memory is cheapest (cheaper than eproms) (and cheaper than roms, unless you plan to order 10,000 pieces or so). And putting the write-logic into the CPLD chip wouldn't increase the cost. The feature doesn't require any additional hardware, so it's useful and free.

And using a SECOND flash chip (like Bryce suggested)... that would increase the cost by 20 cents, and I assume it be a bit more complicated to implement it in the cpld. Using two flash chips would make sense only if one is paranoid about the possibility that the game *could* be overwritten accidently.

I wouldn't be too worried about that, it'll rarely happen, and there are other cheaper ways to prevent it: Put some "If target_address = outside_valid_region then exit" into your write_game_position function, or use an eprom-burner to activate the write-protect feature that is included in the flash chip itself.

Anyways, caring about write-protection would make sense only for "commercially" produced games, in all cases I'd prefer having full write-access to the whole flash memory.
Title: Re: Flash-reprogrammable ROM box
Post by: OCT on 23:07, 17 September 10
Quote from: nocash on 02:16, 13 September 10
> Reprogrammable Rom box
You mean like the ROM boxes that connect expansion rom to the expansion port?
ROM boxes do already exist (maybe no reprogrammable flash-ones)
Isn't that what a http://www.cpcwiki.eu/index.php/SYMBiFACE_II should be if it was available?
Title: Re: Flash-reprogrammable ROM box
Post by: nurgle on 00:41, 18 September 10
Quote from: OCT on 23:07, 17 September 10
Isn't that what a http://www.cpcwiki.eu/index.php/SYMBiFACE_II (http://www.cpcwiki.eu/index.php/SYMBiFACE_II) should be if it was available?


Or the Inicron RRB http://www.cpcwiki.eu/index.php/Inicron_ROM-RAM-Box (http://www.cpcwiki.eu/index.php/Inicron_ROM-RAM-Box)


Or the Ramcard128 from Ram7 http://www.cpcwiki.eu/index.php/Ramcard_128


Btw.: I just stumbeled over this interesting device. The hardware looks a bit overcomplicated to me from the photos, but there might be interesting ideas in it? The Ram7 Cartridge Hacker http://www.cpcwiki.eu/index.php/RAM7_Cartridge_Hacker

Title: Re: ACID chip inside
Post by: andycadley on 12:57, 18 September 10
Quote from: nocash on 21:28, 17 September 10
Anyways, caring about write-protection would make sense only for "commercially" produced games, in all cases I'd prefer having full write-access to the whole flash memory.
I'm not sure that would be terribly useful, you could only program the whole cart from the CPC+ itself if the cart had the programming software on it. And as soon as you overwrote it, you'd be stuck till you reprogrammed it from a PC or other external add-on interface again anyway, rather defeating the object.
To be honest, I'm not overly convinced there is a need to hack a writable solution into the carts anyway, the vast majority of existing 8-bit games got away largely without save game features and whilst they're a nicety I think you'd see better new titles come from have the full 512K available than you would from a small amount of save data.
Title: Re: ACID chip inside
Post by: TFM on 07:01, 19 September 10
Quote from: nocash on 21:28, 17 September 10
How cheaper? Flash memory is cheapest (cheaper than eproms) (and cheaper than roms, unless you plan to order 10,000 pieces or so). And putting the write-logic into the CPLD chip wouldn't increase the cost. The feature doesn't require any additional hardware, so it's useful and free.

Sorry for having been unclear before. I was more thinking about the developpment costs and so on. For me is did sound like a huge lot of sophisticated work to get such an idea running. So somebody invests a lot of time and hardware...
However an EPROM card doesn't need an CPLD, just two or three 74LSomething, which shouldn't be expensive. (Less than 7 Euros?). No need to discuss this in detail  :)  Finally it's just about few bucks.
Title: Re: ACID chip inside
Post by: Trebmint on 12:06, 19 September 10
I don't want to put chips n boards and plastic cases together, eproms, programmable this and that. Somebody please just offer this service so I can code some plus games.

I really think just one person supplying this service would be better than individuals doing it as it would create a style, so people who collect the new carts would have standard looking stock. Same with the box art it should have a standard layout like the original Amstrad carts (if not the same as the old ones)

Title: Re: ACID chip inside
Post by: andycadley on 12:14, 19 September 10
If it helps, Trebmint, I'm considering doing just this. It wouldn't be anything particularly fancy though (no saving inside carts or what have you) and I'd still prefer someone to make a simple USB-able (or similar) user programmable cart as I think that'd be a better long term solution.
Need to look into costs of the various bits and pieces though before committing too heavily to it. And it'd probably need someone far more skilled than my good self, if you wanted nice artwork to go with them. :)
Title: Re: ACID chip inside
Post by: Trebmint on 13:33, 19 September 10
For the artwork you'd just have a basic template as a pdf of a photoshop file with a gap for the pretty pictures to be filled in.

I have 3 partially finished Plus games that I'd love to do a limited cart release of
Title: Re: ACID chip inside
Post by: TFM on 03:25, 20 September 10
Quote from: Trebmint on 13:33, 19 September 10
For the artwork you'd just have a basic template as a pdf of a photoshop file with a gap for the pretty pictures to be filled in.

I have 3 partially finished Plus games that I'd love to do a limited cart release of

Ok, finish one of it. Just one :-) And up to this time we will hopefully have the possibility to produce cheap carts.

Therefore we need (now) only two things:

- The Layout of the cartridge PCB (as exactly as it is on a real cart), in a file format that is suitable to send it to a company producing the PCB.

- The plasic covers.

Any piece of help is appreciated.
Title: Re: ACID chip inside
Post by: jbaudrand on 22:21, 22 September 10
I'm not sure if it helps anyone here:
  for PCB, there is this french company Valadon automation (a famous company that made "le bagnard" arcade game in 1982)
  http://valadon-automation.com/VA_Automatisme.html
 
  For plastic injection:
  you have to make a mold of an amstrad cartridge, and contact a company   that can make plastic injection, it will cost a lot of money. the guy at   atariage and opcodes game succeed to do the mold by themself and contact a brazilian company,   http://www.opcodegames.com/blogs/blog14.htm
 
  Maybe you can contact them to ask them hints and tips.
Title: Re: ACID chip inside
Post by: steve on 23:59, 22 September 10
Instead of injection moulding the cases, you might be able to have the cases made with a 3d printer by a prototyping company, up to a certain number, 3d printing may be cheaper than having a mould made, more than that and injection moulding becomes cheaper.

You might even consider building a REPRAP open source 3d printer and make the cases yourself.
Printing is slow, but if you only want a few hundred, it should be cheaper than having a mould made.
Title: Re: ACID chip inside
Post by: jbaudrand on 05:51, 23 September 10
Oh yes you're right Steve I totally forgot this solution, it's probably the best because until ACID's full emulation, there's only 500 chip available.
Title: Re: ACID chip inside
Post by: Bryce on 09:37, 23 September 10
3D Printers make parts that look nice, but they are very brittle, ie: they break really easily. they are only useful for confirming dimensions and look and feel of a part, they aren't very good for everyday use. We have 3D (SL) printers here at work to confirm prototypes, but the parts often break while just passing them around in a meeting. They also have a very rough surface that would need to be sanded before it would look decent.

As far as moulding is concerned, there are two solutions: Hard moulds can make millions of parts, but they are very expensive (think in 10s of thousands of Euros), but a pre-mould, also know as soft-moulding is much cheaper and can still manage to make a few hundred parts before it looses it's tolerances.

Two suggestions: Find a standard housing that's close enough to be used with minor modifications, or design the unit with a connector/flat cable and a box that doesn't need to fit exactly into the slot.

Bryce.
Title: Re: ACID chip inside
Post by: Gryzor on 09:39, 23 September 10
How long do these materials from 3D printers last? There's that to consider, too, and I have absolutely no idea about these beasts... -ah, oops, Bryce was replying to my question as I was typing it :D

But molds and all that normally cost a LOT of money. In industrial environments (of course we're not there and we don't care so much about building quality or durability) molds  cost real money, and when one breaks it's a really big expense to replace it...
Title: Re: ACID chip inside
Post by: steve on 13:39, 23 September 10
Reprap uses parts in it's construction that have been printed on other repraps so the parts cannot be brittle if they have been printed using the proper temperature and speed.

As for how long the materials last, it's plastic,  it could be broken if you abuse it, but if properly printed it should last as long as a moulded cartridge case.
Title: Re: ACID chip inside
Post by: Bryce on 14:25, 23 September 10
I don't know Reprap, I was referring to SL printers (Stereo Lithography), which is the process I am familiar with. Maybe Reprap are robust enough.

Bryce.

Edit: Ok, I just took a look at Reprap. An impressive idea, but definitely not suitable for this application. The Reprap is really good at making thick solid objects, but the thin walls, latches and shape of a cartridge needed is not within the boundries of what the Reprap can do. I also found their home page a little misleading. They only ever show the production process and the completed part. They don't show how the part looks before it has been sanded and precision filed and neglect to mention that a huge extra machine is required to actually finish the part after the Reprap has done its job (ok, it's shown for a few seconds during the video, but they then quickly move on). In the case of the Cartridge, it would be easier to get a solid block of plastic and use a CNC machine to carve the shape, which is only slightly more work than the step they avoid mentioning too much in the Reprap information.
Title: Re: ACID chip inside
Post by: steve on 20:51, 23 September 10
Some electronic boards are encapsulated in some sort of resin material, maybe the board producers could use the same stuff to create a block of material around the board instead of a case, the board will be inaccessible so repair will be impossible but it is one option if nothing else is affordable.
Title: Re: ACID chip inside
Post by: Bryce on 20:55, 23 September 10
You mean "potting Material", it makes a really robust case, but it's a real mess to work with and it needs some sort of half case to pour it into, but the biggest dis-advantage is as you say, there's no changing / repairing or expanding possible after it's finished, which would be real a pity.

Bryce.
Title: Re: ACID chip inside
Post by: TFM on 15:49, 24 September 10
Now, we got a variety of interesting solutions...

Well, I don't like to search for a similar case, because it will always just be similar, but slowly I think this may be the best solution.
Creating a mold would definitely make more work. And 3D plotting seems to be not state of the art enough to be usable.

Thanks a lot for all the contributions! You provided all very good ideas!
Title: Re: ACID chip inside
Post by: dragon on 15:27, 25 September 10
I will say foolish.

If the plastic is expensive, why not use wood?.

http://www.gadgettastic.com/images/snes_wood1.jpg

Any carpenter could make the case.
Title: Re: ACID chip inside
Post by: jbaudrand on 16:23, 25 September 10
I probably live in wonderland, but why not asking guy at atariage? our loved machine never reach united states, so they probably won't see your project as an opponent. especially if the max limit corresponding to ACID chip. moreover, some of the guy at atariage developp custom PCB they probably have the solution too.

the number of homebrew is exploding on atari because there's some money to catch, if you succeed to make Cartridge for AMstrad I 'm sure we will see a lot of promising game maker come back.
Title: Re: ACID chip inside
Post by: Gryzor on 08:25, 26 September 10
@dragon: +1!
@jbaudrand: +2 (duh...)
Title: Re: ACID chip inside
Post by: Trebmint on 09:13, 26 September 10
I know nothing about plastics etc, so have no real idea except I found this might be a way of making invidiual cases / mold???

http://www.castolite.com/prod01.htm (http://www.castolite.com/prod01.htm)

Title: Re: ACID chip inside
Post by: redbox on 15:28, 26 September 10
The plastic case would be nice, but just the icing on the cake I think.

I'd happily put up with a PCB and no plastic case if it worked  ;)

BTW, this solution for the SNES (http://www.assembla.com/wiki/show/quickdev16) looks awesome...
Title: Re: ACID chip inside
Post by: dragon on 10:49, 30 September 10
And the external box?

i can suggest this?

http://www.mediashelving.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=W&Product_Code=USCG&Category_Code=VHS

upps sorry real price not 42 lol

http://www.shopperinc.com/product.htm?pid=572959&catid=26185

http://www.specialtystoreservices.com/productchild.aspx?group=7673&img=7673.jpg&category=3334
Title: Re: ACID chip inside
Post by: Bryce on 12:50, 30 September 10
They are packaging solutions. The discussion is about the case of the actual cartridge (or at least I thought it was).

Bryce.
Title: Re: ACID chip inside
Post by: Trebmint on 12:50, 30 September 10
I have no idea of the cartridge cases sizes, but the C64 carts seem to be very similar????

http://www.vesalia.de/e_c64cartshell.htm?slc=uk (http://www.vesalia.de/e_c64cartshell.htm?slc=uk)


Whats this, surely not a bastardised orginal case?

http://www.cpcwiki.eu/imgs/thumb/3/30/CPC_GX4000-Multi_EPROM_Cartridge-1.jpg/300px-CPC_GX4000-Multi_EPROM_Cartridge-1.jpg (http://www.cpcwiki.eu/imgs/thumb/3/30/CPC_GX4000-Multi_EPROM_Cartridge-1.jpg/300px-CPC_GX4000-Multi_EPROM_Cartridge-1.jpg)

(oops just noticed it is in effect an original casing)
Title: Re: ACID chip inside
Post by: Bryce on 12:54, 30 September 10
That's what's known as a "cut & shut". I think they glued two old cartridges together to make one.

Does anyone have the exact dimensions of the original cartridge so that we could investigate whether there are any off the shelf cases that would fit?

Bryce.
Title: Re: ACID chip inside
Post by: Trebmint on 13:07, 30 September 10
Quote from: Bryce on 12:54, 30 September 10
That's what's known as a "cut & shut". I think they glued two old cartridges together to make one.

Does anyone have the exact dimensions of the original cartridge so that we could investigate whether there are any off the shelf cases that would fit?

Bryce.

Was just looking at this. I have no idea of the case size, but look similar

http://www.vesalia.de/e_c64cartshell.htm?slc=uk (http://www.vesalia.de/e_c64cartshell.htm?slc=uk)
Title: Re: ACID chip inside
Post by: steve on 14:13, 30 September 10
Dimensions of a cpc cartridge case are 15mm x 65mm x 68mm but this last measurement can be larger as it protrudes from the cartridge slot.
Title: Re: ACID chip inside
Post by: arnoldemu on 14:26, 30 September 10
Quote from: steve on 14:13, 30 September 10
Dimensions of a cpc cartridge case are 15mm x 65mm x 68mm but this last measurement can be larger as it protrudes from the cartridge slot.
it's quite small, but I found this while browsing:

http://www.boss-enclosures.co.uk/Enclosures/Potting_Boxes/Custom_Potting_Boxes

Not sure if this would be any help...
Title: Re: ACID chip inside
Post by: Bryce on 15:59, 30 September 10
Companies like Teko ( http://www.tekoenclosures.com/ ) will make custom housing to the dimensions you want. Not sure what it would cost, but if the order is large enough, I'm sure it's the cheapest solution to get the case exactly as you want it and looking professional. I suspect that the Commodore and Atari cartridge cases available were probably made in a similar way. You'd need to send them a drawing of exactly what you want and the quantity to get an estimate.

Bryce.
Title: Re: ACID chip inside
Post by: redbox on 18:37, 30 September 10
Quote from: Trebmint on 12:50, 30 September 10
I have no idea of the cartridge cases sizes, but the C64 carts seem to be very similar? ???

Could ask the the maker (http://www.icomp.de/) how they did it?
Title: Re: ACID chip inside
Post by: MacDeath on 20:04, 30 September 10
If plastic stuff is to be done, it should get another colour just to differenciate from old carts...

To show it's a new production : cannibal-free

Black would be neat...

Also while in MAdrid I found out the Amstrad Cartridge housing was compatible with an Atari conle one...can't remember which one (but this is not reciproc)

so a casing compatible with both format could be nice...
Title: Re: ACID chip inside
Post by: arnoldemu on 09:52, 01 October 10
Quote from: MacDeath on 20:04, 30 September 10
Also while in MAdrid I found out the Amstrad Cartridge housing was compatible with an Atari conle one...can't remember which one (but this is not reciproc)
Can you remember if the case needs modding, or does it work direct?
Title: Re: ACID chip inside
Post by: Gryzor on 10:30, 01 October 10
While I agree with the color differentiation, and a black cartridge would look cool, try imagining it plugged into a CPC... not good at all :(
Title: Re: ACID chip inside
Post by: Bryce on 10:34, 01 October 10
I'd go for something transperant, so that you can see the bits inside :)

Bryce.
Title: Re: ACID chip inside
Post by: Gryzor on 10:37, 01 October 10
Oooh! Neato! but more expensive, probably?
Title: Re: ACID chip inside
Post by: spybro on 12:01, 01 October 10
a black cartridge looks like this



(http://img52.imageshack.us/img52/4397/im2946.th.jpg) (http://img52.imageshack.us/i/im2946.jpg/)



Title: Re: ACID chip inside
Post by: Gryzor on 12:08, 01 October 10
Grrrrr I can't access Imageshack at work... what's wrong with the forum's attachments? :)
Title: Re: ACID chip inside
Post by: Ygdrazil on 12:13, 01 October 10
Hmmm. I would prefere transparent then  ;D

Quote from: spybro on 12:01, 01 October 10
a black cartridge looks like this



(http://img52.imageshack.us/img52/4397/im2946.th.jpg) (http://img52.imageshack.us/i/im2946.jpg/)
Title: Re: ACID chip inside
Post by: spybro on 12:22, 01 October 10
there you go gryzor ;)
Title: Re: ACID chip inside
Post by: arnoldemu on 12:23, 01 October 10
Quote from: Ygdrazil on 12:13, 01 October 10
Hmmm. I would prefere transparent then  ;D
me too.

MacDeath comes in, teases us with "the cpc+ cart is similar to Atari carts", and then doesn't come back to give more details.
Damn.
Title: Re: ACID chip inside
Post by: spybro on 12:28, 01 October 10
the problem with the transparent ones is that if you dont use high quality plastic it wears off rapidly


Can i ask a question to the makers of the project?


have you finilized the specs?
do you have a timetable for the project?
Title: Re: ACID chip inside
Post by: spybro on 12:42, 01 October 10
Quote from: arnoldemu on 12:23, 01 October 10
me too.

MacDeath comes in, teases us with "the cpc+ cart is similar to Atari carts", and then doesn't come back to give more details.
Damn.


The housing is very similar but certain amendments needed
take a look at here
http://www.pixelspast.com/homebrew/images/2600_housing_front.jpg (http://www.pixelspast.com/homebrew/images/2600_housing_front.jpg)
http://www.pixelspast.com/homebrew/images/2600_housing_back.jpg (http://www.pixelspast.com/homebrew/images/2600_housing_back.jpg)
Title: Re: ACID chip inside
Post by: Gryzor on 12:54, 01 October 10
Quote from: spybro on 12:22, 01 October 10
there you go gryzor ;)

Ooh! Sleek!
Title: Re: ACID chip inside
Post by: Bryce on 13:09, 01 October 10
Here's what the transparent ones could look like. If decent hard plastic is used, then it should stay looking good for years (assuming you don't store it in a box full of sand / blades / assorted scratchy things).

These are made for c64, but whatever company made them, could make the same for CPC for a reasonable price if the quantities are high enough. These are sold for about €4.50 after the reseller has made a profit, so the production price can't be all that bad.

Bryce.

Edit: you could even add some LEDs and make it glow :)
Title: Re: ACID chip inside
Post by: arnoldemu on 13:39, 01 October 10
Quote from: Bryce on 13:09, 01 October 10
Here's what the transparent ones could look like. If decent hard plastic is used, then it should stay looking good for years (assuming you don't store it in a box full of sand / blades / assorted scratchy things).

These are made for c64, but whatever company made them, could make the same for CPC for a reasonable price if the quantities are high enough. These are sold for about €4.50 after the reseller has made a profit, so the production price can't be all that bad.

Bryce.

Edit: you could even add some LEDs and make it glow :)
keep talking dirty....
:laugh:
Title: Re: ACID chip inside
Post by: Bryce on 13:56, 01 October 10
@Arnoldemu: You need to get out more and meet real people. :D

Bryce.
Title: Re: ACID chip inside
Post by: MacDeath on 14:43, 01 October 10
Er... I will try to give you a picture which compare the Atari (5200 or 7800 don't remember) cartridge and an Amstrad...

From what i remember the Atari is sligtly larger (1 milimeter actually...) and lack the dig-in of the Amstrad one (don't knoiw how to tell in English....you know the stuff so you put it in the right side...


So I gessed that if an Atari cart can't fit into an Amstrad computer, an Amstrad Cartridge may fin into an Atari...

But the casing must be able to house both kind of cart-board...

And those are quite different, the Atari being slightly larger...


But at this moment I am cleaning my appartment and doing some paperwork (Administratum...Damn... it will exist even after Humanity disapear from earth...)



The multiEprom cartridge from Spain : I talked with the  guy, he did it with some sort of er... Resin ?

what the name in english again ?

BTW, he did the mold himself but this mold is not getting better with time.

My father has a machine tool, I may try to craft a mold in metal (milling machine)

Just need the proper specifications (Card and Amstrad Socket) and 2 big piece of metal... and time... a properly designed schematic...

But hey, if a commercial company can do it better and not that expensive, why not...But priority is for the Cards and components...

In my opinoion, if we can get a new card, and an old cartridge, we just give those to the plastic company and they craft a proper stuff...then ask for a few hundreds and get the coders and graphists and musician working on GX4000 compatible games... !!!

But it will cost an advance of cash. ouch.
Title: Re: ACID chip inside
Post by: Cpcmaniaco on 18:48, 01 October 10
The person who make it is David (D-O-S).

He make with resin, the kit for make soldiers with warhammer,for exemple.

But with the use need make another.



Title: Re: ACID chip inside
Post by: Bryce on 22:43, 11 November 10
Hi all,
     today I was in the University of Erlangen in the "FAPS" department (where they do automation research). They have a RepRap machine there, which I got a good look at. It really is an impressive little machine, but I spoke with the people who have used it and it definitely isn't the solution for building cartridge casings. For a start, the minimum wall thickness is around 4 or 5 times thicker than a normal cartridge. The second problem is the speed, according to the people I spoke with, a cartridge would take between 7 and 9 hours to "print"!!! Great for one off prototypes, definitely not great for production.

Bryce.
Title: Re: ACID chip inside
Post by: SyX on 22:59, 14 April 11
Well, if you go here (http://www.zonadepruebas.com/modules/newbb/viewtopic.php?start=22&topic_id=11916&forum=2&viewmode=flat&order=ASC). you will see that Mr. Mcleod has made an implementation of the ACID in a CPLD, and he has promised to publish in his web all the details and the verilog source for the CPLD :)

Stay tuned!!!  ;)
Title: Re: ACID chip inside
Post by: Nilquader on 08:43, 15 April 11
There's no need to wait  ;)  I've just put the Verilog code used to simulate the ACID on the Wiki. It was written by Octoate and me at the Xzentrix Party 2010. Schematics for the cartridge will follow as soon as we finished it.

And there are more news: It's possible to start the CPC+/GX4000 completely without ACID by exploiting a timing bug in the CPC+/GX4000 ASIC. It needs just 5 standard components. Photo and schematics are on the wiki. Detailed explanation will follow as soon as i find time for that.

Edit: Why does the CPC+ run without ACID?
As soon as the CPC+ ASIC detects a wrong signal on the SIN line it pulls the CCLR line down (as you can see here: http://www.cpcwiki.eu/index.php/File:ACID_Init_by_Grim.png (http://www.cpcwiki.eu/index.php/File:ACID_Init_by_Grim.png)) The 74AC112N is a RS Flipflop which switches the polarity of SIN as soon as it detects the Pulse on CCLR. (You need the 74AC series. Everything else isn't fast enough and won't work!) The ACID now gets the correct SIN level and sets CCLR high again. And everything runs fine until the ASIC detects the next "wrong" level of the SIN signal. So the CPC+ tells you everything you need to fool him  :D


Title: Re: ACID chip inside
Post by: redbox on 09:34, 15 April 11
All of which is fantastic news!!!


@Nilquader - you say you can start a Plus without the ACID, but does it keep on running?  What happens when the ASIC detects the wrong SIN level again?
Title: Re: ACID chip inside
Post by: MacDeath on 09:36, 15 April 11
Quotetoday I was in the University of Erlangen in the "FAPS" department
:laugh:

http://www.urbandictionary.com/define.php?term=to%20fap
;D :D :laugh:
Title: Re: ACID chip inside
Post by: arnoldemu on 09:43, 15 April 11
Quote from: Nilquader on 08:43, 15 April 11
There's no need to wait  ;)  I've just put the Verilog code used to simulate the ACID on the Wiki. It was written by Octoate and me at the Xzentrix Party 2010. Schematics for the cartridge will follow as soon as we finished it.

And there are more news: It's possible to start the CPC+/GX4000 completely without ACID by exploiting a timing bug in the CPC+/GX4000 ASIC. It needs just 5 standard components. Photo and schematics are on the wiki. Detailed explanation will follow as soon as i find time for that.

Edit: Why does the CPC+ run without ACID?
As soon as the CPC+ ASIC detects a wrong signal on the SIN line it pulls the CCLR line down (as you can see here: http://www.cpcwiki.eu/index.php/File:ACID_Init_by_Grim.png (http://www.cpcwiki.eu/index.php/File:ACID_Init_by_Grim.png)) The 74AC112N is a RS Flipflop which switches the polarity of SIN as soon as it detects the Pulse on CCLR. (You need the 74AC series. Everything else isn't fast enough and won't work!) The ACID now gets the correct SIN level and sets CCLR high again. And everything runs fine until the ASIC detects the next "wrong" level of the SIN signal. So the CPC+ tells you everything you need to fool him  :D
great work!

It is funny that there is a timing bug and that the acid can be replaced with this more simple circuit.

So this will work with any carts? Games too?

So now we need to get those plastic cases ;)

EDIT: I think this working together, and publishing the information is really great for the Plus and future cartridge games.
I think it really helps the Amstrad scene.

I don't think there is any problem with mcleod also making an implementation.
I think it's great to explore all possibilies and discover all the tricks and things we need so that we will finally be able to make cheap cartridges with games on them that others can buy and play on.

Really the case is the final problem that needs to be resolved.
Once I have got my current projects out of the way I plan to work on a cartridge game.

EDIT: Nilquader, please can we have a more closer view of the 74AC112N version?
The picture doesn't do it enough justice.
Title: Re: ACID chip inside
Post by: Nilquader on 13:39, 15 April 11
Quote from: redbox on 09:34, 15 April 11

@Nilquader - you say you can start a Plus without the ACID, but does it keep on running?  What happens when the ASIC detects the wrong SIN level again?


The Flipflop just switches SIN again and the CPC keeps running. Used this Circuit for many hours continuous operation and found no problems.


It works with ANY Cart, even games. Only issue is when using a reset switch in your CPC+: pressing reset is not detected and the SIN level might be wrong (50% chance). Then the CPC shows weird colors and you have to press reset again or switch it off and on. And because of that I recommend the CPLD solution for professional carts.


Quote
EDIT: Nilquader, please can we have a more closer view of the 74AC112N version?
The picture doesn't do it enough justice.

There are just four wires between Cartridge and ACID replacement. Can't be a CPLD or the real ACID. If you don't believe, buy the parts (about 0.50$)  and build it on a piece of breadboard  ;D




Title: Re: ACID chip inside
Post by: TFM on 17:28, 15 April 11
@Nil & Octo: How much would such a solution (for a professional cartridge) cose per unit? Can you please give a rough estimste?
Title: Re: ACID chip inside
Post by: MacDeath on 18:37, 15 April 11
Astute chaps there... 8)
Title: Re: ACID chip inside
Post by: SyX on 09:38, 16 April 11
How i told you yesterday, Miguel Angel (aka mcleod_ideafix) has published all the info about his implementation of the ACID in a CPLD, verilog sources included, you can find here (http://www.zxprojects.com/index.php/analisis-del-chip-acid/62-analisis-del-chip-acid-del-amstrad-cpcgx4000)  :)

Now all the info is in spanish, but include a lot of pictures and if there is interest how with his other projects (i love when he attached a msx vdp to a zx) an english version will appear very soon  ;)
Title: Re: ACID chip inside
Post by: Nilquader on 12:33, 16 April 11
Wow! Lots of information. The pictures look interesting - I hope there will be an english version soon.


mcleod_ideafix used the same Oscilloscope, Logic Analyzer, CPLDs and HDL as Octoate and me did. He must have been at Xzentrix 2010 taking spy pics of our equipment ;)
Title: Re: ACID chip inside
Post by: FatAgnus on 12:48, 16 April 11
Why a translation to English if both have configured your equipment in Spanish?


http://www.cpcwiki.eu/index.php/File:ACID-SIN.jpg (http://www.cpcwiki.eu/index.php/File:ACID-SIN.jpg)


Thanx McLeod, nice pic. Thanx for sharing as soon as you get results.



Title: Re: ACID chip inside
Post by: Nilquader on 13:07, 16 April 11
Quote from: FatAgnus on 12:48, 16 April 11
Why a translation to English if both have configured your equipment in Spanish?

http://www.cpcwiki.eu/index.php/File:ACID-SIN.jpg (http://www.cpcwiki.eu/index.php/File:ACID-SIN.jpg)


Maybe nocash understands Spanish? Or (more likely) he just used the same image. My scope is probably be set to english or german, otherwise I won't be able to operate it  :D
Title: Re: ACID chip inside
Post by: TFM on 17:53, 18 April 11
Quote from: Nilquader on 12:33, 16 April 11
mcleod_ideafix used the same Oscilloscope, Logic Analyzer, CPLDs and HDL as Octoate and me did. He must have been at Xzentrix 2010 taking spy pics of our equipment ;)

Which still makes them the 2. winner ;-)

However, it suxx that you usually get no English translation of abstract from Spanish sites.
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