That ULA CHIP

[radiomarty]

Has been commented on many time that the lack of info on the ULA chip i.e technical data holds everyone back in cracking repair / replacements.Well I was having a look at what MOSI has to offer and just noted that they hold all the technical  / historical files on Ferranti. Has anyone looked through this for data on the chip is it worth a go ?

http://www.nationalarchives.gov.uk/a2a/records.aspx?cat=422-199610_4&cid=-1#-1

[MikeDX]

The main problem with the ULA is that those are basically "blanks" which are then flashed with a circuit to do its job.

It's one thing to know how the blank ULA works, but another to work out what Sinclair did to it.

The guy who completely reversed the ZX Spectrum ULA and I have spoke in detail about this and as to why it's not quite as straightforward as we'd like!

[C5 ENTHUSIAST + RESTORER]

Hi there Mike take a look at the inside of the c5 ULA Chip ....







More to photos follow

[Karl]

Good luck trying to replicate that   

Full respect to anyone that understands this type of stuff 

[MikeDX]

Chas, those pics are awesome. I have seen a very similar set of photos for the Spectrum ULA too - which if we had high enough resolution (and a lot of time) we could decode all the lovely info!

How high of a res do you have? The decapping of a ULA is a BIG piece of the puzzle in the right hands...