CPC 464 prototype with Gate Array simulator board found

Started by balford, 13:58, 27 October 21

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

balford

Anyone who's on FB should take a look at the following link (closed group, so you may need to join):
Amstrad CPC 464 group - prototype CPC

I've suggested the guy loans the machine to someone with expertise in reverse engineering the Gate Array simulator board, as far as I know it hasn't been done yet?

He intends auctioning it, so the more people who can suggest alternatives to stop it falling immediately out of public view the better!

Gryzor

Oh damn. I'm salivating. So what, start a wiki fund or something? Sure, why not. And then... what?

rastislavz

Exactly that was what I have suggested in the FB thread that we could fund it together.
Than somebody wise can analyse the board and make the ULA simulator on FPGA like similar custom chip replacements were made for other 8-bits, e.g. commodore.
The unit could be donated to some retro computer museum.

TotO

"You make one mistake in your life and the internet will never let you live it down" (Keith Goodyer)

Gryzor

Quote from: rastislavz on 15:02, 27 October 21The unit could be donated to some retro computer museum.
...and that's where the problem begins, probably...

I'm all for it, though. There are places where we can raise a common fund, once we agree on the administrator of the fund.

Gryzor

Oh well, never mind, it's already on ebay and with a 3-day limit *repeatedly slaps forehead*


TotO

<< this post can be deleted >>
"You make one mistake in your life and the internet will never let you live it down" (Keith Goodyer)

balford

Disappointing outcome. Hopefully it goes to someone who won't hide it away.

Gryzor


rastislavz

Quote from: Gryzor on 15:23, 27 October 21
Oh well, never mind, it's already on ebay and with a 3-day limit *repeatedly slaps forehead*
Yeah 3 days is not much time to organize something... Guy wants to become rich as fast as possible. Its a pitty. These things usualy end up on somebodys shelf behind the glass.

eto

Quote from: balford on 13:58, 27 October 21I've suggested the guy loans the machine to someone with expertise in reverse engineering the Gate Array simulator board, as far as I know it hasn't been done yet?

As Roland Perry pointed out on FB, there are plenty of PLA chips, so even with this model, it's not easy to reverse engineer the Gate Array.

I was wondering, how compatible the KC Compact is. If I am not mistaken, the GDR engineers already did reverse engineer the Gate Array and replicated it with standard logic chips. WOuldn't that be a much easier way to reverse engineer the logic of the Gate Array? Except for the Gate Array they used either the original chips or clones, so I would expect, that their Gate Array logic should be close to identical.

gerald


Quote from: TotO on 15:10, 27 October 21
@gerald is called here.
shout louder ! Notification does not seem to work   ;D
Quote from: eto on 17:24, 27 October 21As Roland Perry pointed out on FB, there are plenty of PLA chips, so even with this model, it's not easy to reverse engineer the Gate Array.
Yes, at least 9 of them. But if these are just PAL (not using registers) it should be doable. With registers it will just make it a bit more complicated.
However the SOLD AS SEEN UNTESTED (MAY NOT WORK) is a big showstopper for me.



eto

Quote from: gerald on 18:14, 27 October 21Yes, at least 9 of them. But if these are just PAL (not using registers) it should be doable.

Have you ever thought about using the schematics of the KC compact? I had a quick look and it doesn't look like they have any PAL but only (many) standard logic ICs.

gerald

Quote from: eto on 18:20, 27 October 21Have you ever thought about using the schematics of the KC compact? I had a quick look and it doesn't look like they have any PAL but only (many) standard logic ICs.
I must confess, I never look at the KC compact  :picard:
A quick look show that it is not an exact emulation of the CPC GA. Interrupt are coming from a z8536, mode 3 is different as well as some other bits (https://www.cpcwiki.eu/index.php/KC_Compact#Hardware_differences)

On the schematic, you can also see that they are using a 2716 eeprom as a PAL equivalent.

TotO

I think the Aleste 520 schematic is better for that.
"You make one mistake in your life and the internet will never let you live it down" (Keith Goodyer)

xesrjb

At last jesus6128 Ebayer from Spain will get it for 1000 £...


xesrjb
,,The pellet with the poison's in the vessel with the pestle; the chalice from the palace has the brew that is true."

Gryzor


TotO

The item condition will probably require to be fixed to work again if no issue from the GA board.
Sad to see the keyboard missing a key and was not the original. The same for the bottom case.
"You make one mistake in your life and the internet will never let you live it down" (Keith Goodyer)

dragon

I'm not in the Facebook  group someone can put pictures?

Richard_Lloyd

Richard
CPC464, CPC6128, PCW8512, PCW10, BSA & NSP

Richard_Lloyd

https://www.theregister.com/Print/2014/02/12/archaeologic_amstrad_cpc_464/


The photos in this article have different coloured base and front just like the one for sale.......
Richard
CPC464, CPC6128, PCW8512, PCW10, BSA & NSP

00WReX

Quote from: TotO on 22:17, 27 October 21
The item condition will probably require to be fixed to work again if no issue from the GA board.
Sad to see the keyboard missing a key and was not the original. The same for the bottom case.
I think the bottom of the case is original. I have seen two others and they are the same. The key thing is that the production models had 5V 2A on the sticker...the development have 5V 1.5A.

Cheers,
Shane
The CPC in Australia...
Awa - CPCWiki

Gryzor

Well, Perry says it's not an original, based on the label...

00WReX

Quote from: Gryzor on 12:42, 28 October 21
Well, Perry says it's not an original, based on the label...


He actually acknowledged what I said...


"Thanks for that information. There must be two generations of grey 464 - because I've seen ones without the black label on the base."
The CPC in Australia...
Awa - CPCWiki

Gryzor

Missed that comment. However that looks like a production label, it'd be weird if it belongs to a prototype, especially since other labels and markings are paper, half glued ones.

Powered by SMFPacks Menu Editor Mod