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Re: Ithaca Audio Z80 board kit UP & Running with custom monitor!



Hi Fabio,
I have the same card but a V1.03 that I got on eBay, worked OK with the original 2708. I noticed though that some mods were done on the board. As I could not read or write the 2708 with my EPROM programmer I decided to replace it by a 2732 and modified the board accordingly. When PROMing a simple program including HALT at the end, I noticed the jump-on-reset to my EPROM is working approx 1/3 times... I think I narrowed this down to the SET input of the 7474 that is used to tri-state the buffers until the Z80 reached the EPROM address. Surprisingly, it triggers while the address bus is still in tri-state, so I was wondering if I need to put some pull-down resistors on the address bus, or check the reset timing..?
Did you make some modifications to have your card work with a 2732 (or is your version already compliant with it ?). Did you experience any issue with the jump-on-reset circuitry ?
If you could send me the schematics of your board that would be great as I am sure some bugs from V1.03 were corrected in your version..
thanks in advance for your feedback !
philippe