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Re: Z80 CPU board - D2/D3 port timing problem

Hi Phillipe,
Just for clarity, are the chips you are referring to (the ones you swapped out) on the console I/O board ?
I think I also have an intermittent console I/O timing issue, every so often when booting my system to CP/M from the Z80 monitor ('P' option) the system fails to boot and the led on the console board that indicates a waiting character fails to go out, subsequent key presses then fail to have any effect on the system as the previously presed character has not been read/cleared. At this point I power down the system and power up again and all is ok for a while.
would be interesting to see if this chip swap out you mention will resolve my intermittent console I/O issue.
S100 Z80 Master CPU board @ 10Mhz
S100 CF/IDE board
S100 Console I/O board
S100 RAM/ROM board V2
Active terminated backplane
David fry

On Sunday, November 23, 2014 12:20:52 PM UTC, Philippe Elie wrote:
Hi folks,
a quick update in case this can be of interest to others : even after the above modifications, I ran a infinite test loop (a turbo pascal program incrementing an integer and displaying the result) and discovered the display was hanging after around one hour.
I ran a RAM test with no IOs that worked perfectly well. I started to suspect the console IO timing, and indeed that was the issue : i swapped the 244, 32, 04 and 00's for F versions, and the turbo pascal loop is not running since more than 3 hours. 
note than i use one one wait state for IO, RAM and ROM with a 10 MHz oscillator.