FPGA replacment for the ZX8301 ULA and more

[lliont]

It a matter of 3-4mm
I use these pins that are perfect for round pin sockets and are thin enough not to destroy the others unless you insert and remove many times.

if only they where a bit longer from either top or preferably bottom side.

[ones' complement]

I'll reconsider the expansion port but new pcb from the begining and new tests ... :

Ah, it was only theoretical question not practical. Your achievement this far has been tremendous

I have to admit that there is a problem with those red tall cpu sockets

They are very flaky, easily splitting into two which makes then the simplest socket to replace (pins can be removed one by one). Turned pin strips (or 2x DIP24) would provide best anchor for board.

[tetroid]

It a matter of 3-4mm
I use these pins that are perfect for round pin sockets and are thin enough not to destroy the others unless you insert and remove many times.


5272971692517406008.jpg

if only they where a bit longer from either top or preferably bottom side.

Hi.

We can't find the long round connector, but we can use the short connector instead the normal and the normal instead the long.

[lliont]

Nice I'll look for the short one, thanks.

[tetroid]

https://www.ebay.com/itm/170850554439

[Peter]

PCEN

Not obvious to me why you'd need that.

[ones' complement]

PCEN peripheral chip enable. Surely any ZX8301 replacement will need to provide it for ZX8302 on pre issue 6 QLs (also TXOE).

[Peter]

PCEN peripheral chip enable. Surely any ZX8301 replacement will need to provide it for ZX8302 on pre issue 6 QLs (also TXOE).

Thanks, I forgot and just looked at the issue 6 schematics. Pity an expansion port solution fails just because of that.

Another thought might be whether the ZX8301 needs to be replaced at all, if its video signals (the weak spot) were no longer used. New ones could be accessible at the expansion port. This board is no timing compatible replacement anyway, so going the "GoldCard" way - just with video - could make sense.

[lliont]

I'll think about how it could be adapted to use the expansion port when I find some time, I am busy with some other things these days.
Worst case I could simply use few cables to the socket or something.

[Chris_68]

Hi

Leon, great work as always.

I haven't all the posts but could it be possible to use your PCB and design an adapter board with the socket for CPU and 8301 routed to a DIN41612, this instead of having to reroute the PCB?