>> One confusing thing is in what respect are we talking about read and write.
>> In terms of the S100 bus/CPU or
>>the 8255. Let’s talk in terms of the CPU.
>> Dave since you feel the problem is just with the CPU WR* signal
>> (particularly the 68K), then I will go back to
>>using the 74LS244 for the CPU read (S100 bus DI lines).
When I designed my 68K SBC, I had a great deal of difficulty with the 68K R/W*
signal (particularly with reads, as I remember it). I was able to get a CF to
work well with the Z80 (two SBC's) directly (no 8255), but the CF seems to like
a clean write or read pulse, and the 68K R/W* just didn't seem to do it. I had
to go with an 8255 to get the CF to work with a 68K. And it works quite well
that way. Maybe that's what you need to focus on with the 68K CPU card (clean
up R/W*)???
Roger
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