Replacement A3000 motherboards

[a1exh]

I noticed on Amibay (Amiga selling site) the other day that there has been a successful recreation of the Acorn A3000 motherboard.

No real details other than the three photos below. Apparently Rob Taylor and Chrissy on the Retro Tinkering Discord server? (I am not a member).

Anyone have any more details?

[baz4096]

The discord doesn't seem to contain too much detail, mostly just status updates. There's more information posted on X/twitter:

https://twitter.com/search?q=%40peepouk ... yped_query

Rob Taylor (@PeepoUK, "Chrissy" (@Chris_JH) and Ian Cudlip (@grandoldian) are the bods responsible, and I believe IanJ has a fully populated board.

[a1exh]

Ooooo. Thanks.

I can't find any open source repo though. Nor anyone selling them

[IanJeffray]

Anyone have any more details?

A production run has been ordered. Patience.

[paulb]

A production run has been ordered. Patience.

Have you also booked the fab for all the chips, too?

[IanJeffray]

A production run has been ordered. Patience.

Have you also booked the fab for all the chips, too?

They're not much of a problem to source - just IOC/MEMC/VIDC/ARM - everything else is available brand new from disties. I've built up two now, from fully new parts. Here's the state of one as of last November, mostly built, but also with some of my own additional upgrades onboard (this also explains the mod wires, BTW):

[strobe84]

This is just full on awesome.

[IanJeffray]

Subsequent to questions:
1) The ROMs are set up as usual - my board just has my extra '4MB' carrier on it for fun (with LA21 patch wire). The motherboard also has new support for 'Flash' ROMs (eg 39SF040).
2) The RAM's removed on my board just to make fitting the 16MB easier - the motherboard supports the original 1MB as usual, but also by means of a new link, can actually support 4MB directly onboard which is lovely - and I've actually got another board set up this way.
3) The connector at the front by the ROMs is a proper "POST" header.
4) The two links north of the 1772 allow selection of filtered/unfiltered sound - no more bodges required.
5) The two links south of the speaker connectors supply signals to previously unused pins on the external podule connector to allow use of my triple-podule backplane.
6) The keyboard controller 8051 doesn't need to be sourced from a donor board - with appropriate motherboard configuration, a brand new Atmel part can be programmed and used (I have). It really is possible to build this board from fully new components, bar the 'big four' ICs.

And FWIW, I had basically nothing to do with this project - I just built and tested a couple of boards, for which I was grateful of the opportunity. Some issues were found with the first spin, all resolved now. Al credit to 'The Board Folk' as Baz mentioned above. The project is more than just a functional re-creation; the precise layout and even the precise signal routing has been carefully copied from the original board!

[paulb]

The project is more than just a functional re-creation; the precise layout and even the precise signal routing has been carefully copied from the original board!

Well, I suppose the issue of leaking battery damage must be experienced or at least appreciated by future generations, too!

[IanJeffray]

The project is more than just a functional re-creation; the precise layout and even the precise signal routing has been carefully copied from the original board!

Well, I suppose the issue of leaking battery damage must be experienced or at least appreciated by future generations, too!

No, we install AA NiMH (never seen one of those leak) offboard, in a box - notice the pins on the board, not a battery.

[paulb]

No, we install AA NiMH (never seen one of those leak) offboard, in a box - notice the pins on the board, not a battery.

Was just joking, and I'm sure guidance will be given to those populating these things.

[grandoldian]

Hi all,

If you haven't seen, Rob's put these up on his Tindie now..

https://www.tindie.com/products/bobsbit ... plica-pcb/

atb,
Ian

[wmd]

Would love to see this shrunk so that it could be put into an A3xx / A4xx / A5xx case.