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Re: Z80 CPU Speeds? - Upgrading



Eric Smith wrote:
"Brian A. Davis" <badavis@nbnet.nb.ca> writes:

Sorry, Roy. I was not specific enough. I have a PCPI Appli-card with a 6 MHz Z80B. On board the Appli-card is a 12 MHz oscillator. This is what I was thinking of changing. I did not mean the oscillator on the Apple IIe motherboard.

The PCPI Appli-card has its own 64k RAM bank, so the only interactions between the card and the Apple IIe motheboard are I/O calls (I think).


It *might* work.  But even if it seems to work, I wouldn't count on it
being reliable.  Running it faster than designed will probably result
in the memory timing being on (or over) the hairy edge.

Faster memory chips might help, but I'd be more concerned with how the card interfaces with the II. Since I have the same card, Brian, I'd be glad to let you experiment with yours and let me know if it works, and is safe for mine... ;-)

Roy