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General Category => Amstrad CPC hardware => Topic started by: Carnivius on 13:51, 18 August 11

Title: Want to upgrade 64k to 128k
Post by: Carnivius on 13:51, 18 August 11
Alright, I'd like to get a memory expansion for my CPC 464 just to make use of 128k only features so I can have the music in certain games that the standard 464 set up doesn't do and I think a few other games did speech or had extra graphics or something appear.  Anyways what exactly am I looking for, how much would it tend to be and is it easy to just put into the CPC?  I know nothing of this stuff, I got familiar with PC upgrading before I gave up on it all and I'm ok with Amiga stuff but it never even occured to me back in the day that I could upgrade the 464.

Thank you.
Title: Re: Want to upgrade 64k to 128k
Post by: Gryzor on 15:15, 18 August 11
Well, the standard method is to find an external mem expansion. These came in 64k and 128k flavors and in their own box which you attached to the expansion port. So assuming you hit one on eBay it's really easy to use - just connect it.
Title: Re: Want to upgrade 64k to 128k
Post by: Carnivius on 15:46, 18 August 11
I've had it on ebay search emails for a lil while.  How far do they stick out the back?  My CPC doesn't have much room available on it's desk (cos it shares it with the Amiga and they have a screen each)
Title: Re: Want to upgrade 64k to 128k
Post by: steve on 18:51, 18 August 11
CPC-Wiki lists many memory expansions, but this is what you are most likely to see on ebay, although they are very rare.
http://www.cpcwiki.eu/index.php/Dk%27tronics_memory_expansion (http://www.cpcwiki.eu/forum/../index.php/Dk%27tronics_memory_expansion)
Title: Re: Want to upgrade 64k to 128k
Post by: Cholo on 21:16, 18 August 11
@Carnivac: being a 464 user myself i feel i should warn you about a couple of things.

First: if your intent with the ram expansion is to play the commercial 128k games then i think its better to get 6128 instead. First of it will be MUCH cheaper and easier. As those ram expansions are extremely rare its probably impossible to get on for less than £60 (and like a ebay auction can skyrocket beyond £100+ .. especially if its open to europeans too).

Second: ive got at 256k dk'tronics expansion for my 464 and a DDI drive as well. The dk'tronics one is basicly the closest thing you can get to a "official" ram expansion i guess. Sadly, adding 256k module (and DDI) dosnt turn my 464 into a 6128. And from my own experience id say that most of the games with "additional" feature only work on a real 6128. Not going too deep into details but most of the times its that the games simply dont recognise the extra ram .. or like Addams Family the program has been saved to tape in one huge file that the 6128 can handle "natively" but the 464 cant. Then there is simply the size of the games like Pirates, Defender of the crown etc, that are so big and need to load all the time so having a disc drive is vital as well.

Anyways my point is: If you want to play the commercial games, you can get a 6128 for like £20-40 on ebay (and a powersupply and scartcable as well) and it will play 99.99% of the games.

If however you reason to get a ram module is because you are a programmer or graphics artist and want a easy way to move data around (like 16k pictures) then you can go ahead of cause.

Not trying to scare you off of buying a ram module but its good to know what you are actually getting. Also even tho im a hardcore 464 fanboy i must admit that the 6128 simply is that more easy  (and cheaper) to expand in any way (like you can basicly add either a 5,25" drive, 3,5" or HxC SD floppy emulator straight up) and if you want to play around with FutureOS, SymbOS etc. its the only way.

Also i remember back being a kid with a £10 allowance a month, freaquently sneaking into my rooms when i was all alone, picking up some dirty mag and flicking to the centerfold pages and having a good long oogle & drool over those beautifull dk'tronic modules  ;D And thinking .. "if i had one of those all my problems would be solved". Alas 20 years later i got one and must admit slight .. dissapointment.
Title: Re: Want to upgrade 64k to 128k
Post by: Gryzor on 10:46, 19 August 11
Well, think of it this way: if you got a Playboy centerfold from 1985 *today* you wouldn't be having such a good time, either.

By the way, I got hold of the latest Greek Playboy issue; they've done away with the centerfold altogether! What kind of marketing-illiterate mind would do that...
Title: Re: Want to upgrade 64k to 128k
Post by: Bryce on 10:52, 19 August 11
Don't you just buy it for the interesting articles, like every other man on the planet ;) :D

Bryce.
Title: Re: Want to upgrade 64k to 128k
Post by: Carnivius on 12:44, 19 August 11
Thanks for the advice but I don't have the space for a 6128 (I didn't sell off a load of old game consoles just to collect more old stuff to use up my room) and I don't really want one.  I just want my trusty old 464 that I grew up with to have a bit more memory in it and hope some games make more use of it (Switchblade playing it's excellent music is what I want, it sucks not being able to hear it on a 464).  I've no use for all that fancy OS stuff either.  I'm not an Amstrad fanatic or anything.  I just love my 464.
Title: Re: Want to upgrade 64k to 128k
Post by: Gryzor on 13:50, 19 August 11
I understand what you're saying; when I started collecting, some ten years ago, I got me a 464 and I was mighty happy with it. And I decided to live with its shortcomings for a long time... so the most hassle-free solution would be for you to fork out for a mem expansion once one appears on eBay, and that would be it. You're not missing much anyhow...
Title: Re: Want to upgrade 64k to 128k
Post by: Carnivius on 17:19, 19 August 11
Yeah I'll be patient some more. Like I said I'd just be happy if I could play Switchblade with full music without just carrying my laptop or PSP in there to play the tune on that while I play the game on my CPC.  My Amstrad CPC 464 was my first ever computer and I spent so much time on it growing up and the fact I still have it with me 27 years later and still working in perfect condition long after I've owned and sold or replaced various other computers says something about how much that old beepy tunes, blocky graphics machine means to me.  Just wouldn't feel the same attachment to any other CPC no matter if it is superior, not even another 464 would be the same to me.  Think I'm a bit sentimental about some things.  I'll keep looking for the memory attachment on ebay with the auto emails thingy and maybe someday I can give my 464 the gift of another 64k. :)

Thanks for all the advice and help though  ;D
Title: Re: Want to upgrade 64k to 128k
Post by: CraigsBar on 21:16, 19 August 11
I think I might have one here.

I am sure I do not want *that* much for it :)

I'll have a check through my various CPC boxes and let you know what I find


*Edit*

Yep I found it and I also found the 8 RAM chips I was planning on using to upgrade the capacity to 256k

Send me a private message if you are interested in this.
Title: Re: Want to upgrade 64k to 128k
Post by: Carnivius on 07:41, 20 August 11
done :)
Title: Re: Want to upgrade 64k to 128k
Post by: Gryzor on 12:15, 20 August 11
...another satisfied customer :)
Title: Re: Want to upgrade 64k to 128k
Post by: CPCLER on 12:29, 20 August 11

Hi


My preferred memory expansion for the CPC464 (or CPC6128) is the http://www.cpcwiki.eu/index.php/Dobbertin_Memory_Expansion (http://www.cpcwiki.eu/index.php/Dobbertin_Memory_Expansion), it can be configured to hold 512Kb. And makes the CPC464 able to do 64Kb switching.


/CPCLER

Quote from: Cholo on 21:16, 18 August 11
@Carnivac: being a 464 user myself i feel i should warn you about a couple of things.

First: if your intent with the ram expansion is to play the commercial 128k games then i think its better to get 6128 instead. First of it will be MUCH cheaper and easier. As those ram expansions are extremely rare its probably impossible to get on for less than £60 (and like a ebay auction can skyrocket beyond £100+ .. especially if its open to europeans too).

Second: ive got at 256k dk'tronics expansion for my 464 and a DDI drive as well. The dk'tronics one is basicly the closest thing you can get to a "official" ram expansion i guess. Sadly, adding 256k module (and DDI) dosnt turn my 464 into a 6128. And from my own experience id say that most of the games with "additional" feature only work on a real 6128. Not going too deep into details but most of the times its that the games simply dont recognise the extra ram .. or like Addams Family the program has been saved to tape in one huge file that the 6128 can handle "natively" but the 464 cant. Then there is simply the size of the games like Pirates, Defender of the crown etc, that are so big and need to load all the time so having a disc drive is vital as well.

Anyways my point is: If you want to play the commercial games, you can get a 6128 for like £20-40 on ebay (and a powersupply and scartcable as well) and it will play 99.99% of the games.

If however you reason to get a ram module is because you are a programmer or graphics artist and want a easy way to move data around (like 16k pictures) then you can go ahead of cause.

Not trying to scare you off of buying a ram module but its good to know what you are actually getting. Also even tho im a hardcore 464 fanboy i must admit that the 6128 simply is that more easy  (and cheaper) to expand in any way (like you can basicly add either a 5,25" drive, 3,5" or HxC SD floppy emulator straight up) and if you want to play around with FutureOS, SymbOS etc. its the only way.

Also i remember back being a kid with a £10 allowance a month, freaquently sneaking into my rooms when i was all alone, picking up some dirty mag and flicking to the centerfold pages and having a good long oogle & drool over those beautifull dk'tronic modules  ;D And thinking .. "if i had one of those all my problems would be solved". Alas 20 years later i got one and must admit slight .. dissapointment.
Title: Re: Want to upgrade 64k to 128k
Post by: Gryzor on 12:45, 20 August 11
I always wanted one of these... But with the MF it'd be a bit over the top now :)
Title: Re: Want to upgrade 64k to 128k
Post by: CPCLER on 13:21, 20 August 11

MF?  :blank:

Quote from: Gryzor on 12:45, 20 August 11
I always wanted one of these... But with the MF it'd be a bit over the top now :)
Title: Re: Want to upgrade 64k to 128k
Post by: Gryzor on 14:48, 20 August 11
MegaFlash!
Title: Re: Want to upgrade 64k to 128k
Post by: TFM on 02:40, 29 September 11
Quote from: Gryzor on 14:48, 20 August 11
MegaFlash!


Well, I'm so tired, I try to hit Quote, no Reply I guess. Whatever, at least this way I made your LIKED to a solid 100!


Ahem... to topic! As I see there is need for a RAM expansion, compatible to the Amstrad standard (which means dk'tronics and Dobbertin). However if we use todays RAM, then we can easily use 4 MB RAM and stay compatible to dk'tronics, Dobbertin, RAM7's 2 MB and Jareks 4 MB.




Bryce, that should be our next project!


And we can adapt the R-DOS to have a 4 MB RAM drive. Jeeeehaaaaaaaaaaaaaaaa!


Going to bed now...j

Title: Re: Want to upgrade 64k to 128k
Post by: Gryzor on 08:03, 30 September 11
(ooh, 100! I feel the glory!)

So, a MegaFlash II that will include a memory expansion as well? Is that possible?
Title: Re: Want to upgrade 64k to 128k
Post by: TFM on 18:16, 30 September 11
Quote from: Gryzor on 08:03, 30 September 11
(ooh, 100! I feel the glory!)

So, a MegaFlash II that will include a memory expansion as well? Is that possible?

That's strictly confident, but you will not have to replace the expansion which you own now :-)
Title: Re: Want to upgrade 64k to 128k
Post by: Gryzor on 07:25, 01 October 11
Ohhh a teaser!
Title: Re: Want to upgrade 64k to 128k
Post by: Bryce on 12:43, 01 October 11
There are several RAM expansion ideas being contemplated at the moment. But that brings me to a question that maybe someone here can answer: Some RAM expansions have been described as 100% DKTronics compatible and others (Inicron I believe) are described as not fully DKTronics compatible. My question is, what makes them only "almost compatible", and what's the definition of 100% DKTronics compatible.

Bryce.
Title: Re: Want to upgrade 64k to 128k
Post by: SyX on 13:59, 01 October 11
I'm going to explain a typical 64 KBs ram expansion, equivalent a how work the ram paging in a 6128 ;)

A typical RAM expansion put the expansion ram pages between $4000 - $7FFF, and you select a new ram page with OUT &7F00,&Cx (4 < x < 7 in a 64 KBs ram expansion) and with OUT &7F00,&C0 put again the default ram page there.

For example, if the normal ram pages on a CPC are 0, 1, 2 and 3; and the expansion ram pages are 0*, 1*, 2* and 3*. When you switch on the CPC, the z80 see this ram configuration 0 1 2 3 and after a OUT &7F00,&C6 would be 0 2* 2 3. And with an OUT &7F00,&C0, the z80 will see 0 1 2 3, again.

Well, for being 100% DKTronics compatible (or Amstrad compatible, because that's how work the PAL from the 6128) need to support the 3 special modes:

1.- OUT &7F00,&C1 : Put the extension ram page 3* between &C000 - &FFFF (0 1 2 3*)

2.- OUT &7F00,&C2 : Make all the extesions page visibles to the Z80 (0* 1* 2* 3*), this config is used by CP/M+ for example.

3.- OUT &7F00,&C3 : Is similar to &C1, but also the ram page 3 appears between &4000 - &7FFF (0 3 2 3*)

And that's all :)

For expansion until 512KBs (for bigger expansion they use additional I/O ports), that is how they are working, the expansion ram is divided in blocks of 64 KBs, and you select which 64 KBs blocks are you using.  More exactly the byte that you are sending to &7F00 is %11 bbb ppp (in binary) , where bbb select the 64 KBs block (0-7) and ppp the pages how we have seen before.

You can find a better explanation here (http://www.cpctech.org.uk/docs/rampage.html) and here (http://www.grimware.org/doku.php/documentations/devices/gatearray#mmr).

PD: It's important to note that the pages of the ram expansion are only visible to the z80, because that we can not use them how video ram :( , in the PCW you can use the first 128KBs how video ram... and for the Amiga people it would be the equivalent to the CHIP ram ;)
Title: Re: Want to upgrade 64k to 128k
Post by: Bryce on 12:02, 02 October 11
Thanks. I'll have to read that a few times before it has all been understood :D

Bryce.
Title: Re: Want to upgrade 64k to 128k
Post by: Johnny Olsen on 13:09, 02 October 11
Try to look at this chart - maybe it will help
Title: Re: Want to upgrade 64k to 128k
Post by: MacDeath on 20:25, 02 October 11
A little question here.


Many classic Ram expansion came in 2 variant if I remember correctly...
those for 464/664/X64... an,d those for 6128...


The thing was (if I remember well) that a simple +64K (dk tronic or dobbertin ? both) put on a 6128 would not work as it simply take place of the existing +64k RAM on the motherboard...

As a result you need a more than +64K only expansion to actuazlly improve the RAM...


Can someone explain me better ? Is there a way to still get the existing+64K on board usable ?

Title: Re: Want to upgrade 64k to 128k
Post by: steve on 22:10, 02 October 11
The dk'tronics ram disabled the second internal 64k in a 6128, so if you use a 256k rampack you get 320k memory available on a 6128, I do not know if it is the same for other memory expansions and I do not know if there is any way to reactivate the second 64k bank.
Title: Re: Want to upgrade 64k to 128k
Post by: TFM on 03:42, 03 October 11
Quote from: Bryce on 12:43, 01 October 11
There are several RAM expansion ideas being contemplated at the moment. But that brings me to a question that maybe someone here can answer: Some RAM expansions have been described as 100% DKTronics compatible and others (Inicron I believe) are described as not fully DKTronics compatible. My question is, what makes them only "almost compatible", and what's the definition of 100% DKTronics compatible.

Bryce.

Boiled down:

Half way compatible means banking of 16 KB blocks to &4000-&7FFF by using: &C4..&C7 and &CC..&CF (and the same for &D4... , &E4...., &F4....).
Further banking/switching of whole 64 KB blocks


100% compatible in addition means to support configurations &C1 and &C3. This is important for banking a 16 KB block to &C000 - and in the same time to move the screen from &C000 to &4000. Actually that logic is part of a PAL in the 6128. Therefore 464/664 can (natively) not run CP/M Plus (or SOS or FutureOS).

However some RAM expansions like the 512 KB from Dobbertin can cope with that problem and allow CP/M Plus on 464 / 664.

I tried to keep is short for the beginning.
Title: Re: Want to upgrade 64k to 128k
Post by: TFM on 03:47, 03 October 11
Quote from: steve on 22:10, 02 October 11
The dk'tronics ram disabled the second internal 64k in a 6128, so if you use a 256k rampack you get 320k memory available on a 6128, I do not know if it is the same for other memory expansions and I do not know if there is any way to reactivate the second 64k bank.

The Inicron RAM expansion has a switich for that 64 KB. And this makes sense, since the Inicron 512 KB is battery buffered SRAM.

But you can't use both 64 KB blocks at the same time.
Title: Re: Want to upgrade 64k to 128k
Post by: TFM on 03:52, 03 October 11
Now how to use more than 512 KB RAM?

Well, by using port &7Fxx you can manage 512 KB in a compatible way.

Now you can use ports &7Fxx, &7Exx, &7Dxx, &7Cxx, &7Bxx, &7Axx, &79xx and &78xx to manage 512 KB each. And 8 * 512 KB makes 4 MB. I do not suggest to use ports &77xx... &70xx though.
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