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Re: [N8VEM-S100:6293] Re: An updated (V3) version of our Dual IDE/CF card S100 bus board




>> 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