Who has an Issue 1 or Issue 2 Spectrum??

edited November 2007 in Games
Do you have an Issue 1 or 2 Spectrum (ie machines with 5C102E and 5C112E ULA's) ???

I'm doing a lot of research into the ULA and also the reasoning behind some of the 'standard modifications' that were made (as seen for instance in the ZX Spectrum Service Manual) for what will be a free book "The ZX Spectrum ULA".

One of the big questions relates to the transistor mod that was made to issue 2 machines - the feeling is that it would also have applied to the issue 1 machine, even if never implemented.

Secondly, does the RAS line of the ULA _ever_ go high impedance - this is a memory refresh issue.

Tracking down people with Issue 1 or 2 machines is one hurdle. Working out how to answer the questions from that is another problem.....

You can contact me via here or via my site http://www.nfluid.com/specDesign

Thanks everyone!
Sign In or Register to comment.