EPROM duplication ?

deni14 · Post by **deni14** » Thu Sep 03, 2015 4:23 am

In reading about the life span of our EPROMs I have become more concerned about preservation of these chess computers. Some are more delicate and perhaps we should be doing more now. Just what to do I do not know, but I read about EPROM copying devices that may help. Which models are most vulnerable to failure, and what could we be doing now to help? Thanks!

Dennis

IvenGO · Post by **IvenGO** » Thu Sep 03, 2015 5:51 am

Loosing data from EPROM is a kiind of rare failure problem I think because factory installed chips are UV-type, but different logic chips can loose data commonly as they are EE-type and this make them vulnerable ...

deni14 · Post by **deni14** » Fri Sep 04, 2015 2:49 am

My understanding is that these EPROMs have a finite life span that most people believe may be 25 to 50 years. Also that these EPROMs can be reprogrammed to extend life another 50 years. I read about new self repairing Eproms! I do not know about copy rights, and other complicated issues, but believe that planning ahead to protect these little gems is worthwhile. I am hopeful that people who have knowledge and experience will add to this discussion. Thanks for your reply!

trontreez · Post by **trontreez** » Fri Sep 04, 2015 5:12 am

I also agree that we should be copying, storing and sharing our ROMs as much as humanly possible. I not too sure about ownership and copyright laws but I think the authors would be happy for us to keep their work alive. Unfortunately most of the people hear don't seem to interested in sharing ROMs files.

trontreez · Post by **trontreez** » Fri Sep 04, 2015 5:18 am

IvenGO wrote:Loosing data from EPROM is a kiind of rare failure problem I think because factory installed chips are UV-type, but different logic chips can loose data commonly as they are EE-type and this make them vulnerable ...

Maybe you can help me with your EPROM knowledge. I have a fidelity designer display 2100. It powers on all fine but when playing chess it doesn't follow the correct rules of chess. I cannot capture a piece that gives check even if it's a legal move. I just assumed it would be the game ROM causing this fault and was looking to source a replacement. But you suggest it may be a logic chip? Any ideas how I can test these chips? Or I just have to copy and replace each chip (from a working board) until it works properly?

Curious regards,

Your Pal
tt

ricard60 · Post by **ricard60** » Fri Sep 04, 2015 4:57 pm

After powering up and before start playing do the following:

1) Empty the board using the comands that are in the manual.
2)Then put any middle game or end game position and try to start to play from there.

Strange problem regards
Ricardo

deni14 · Post by **deni14** » Sat Sep 05, 2015 2:09 am

Fascinating reading in Wikipedia about 7400 series logic chips, DIPs etc. So I am guessing that the earlier circuit boards used separate EPROMs and logic chips, both of which could malfunction. Also that by the example given, ie an end game analysis, one could determine what the error could be...but not where on the board you could find the faulty DIP?