Hello! Ethan Dicks wrote: > EPROM solutions are easy to implement - the PLA is essentially a > "fast" (by 1982 standards) EPROM, not a PAL/GAL. Well, internally, it's a PAL, not an EPROM ;-) > I haven't memorized the access time of the 82S100, but an EPROM > with an equivalent (or better) value will drop in there nicely. ISTR it > takes a 27C512 or so, but someone who's done it can certainly > quote exact values. Wasn't that actually a problem that a typical EPROM was _too_ fast compared to the old PLA, for some critical timing in the C64? Then there also is a problem that an EPROM modifies its outputs differently than a PAL when the inputs start changing. A PAL, based on logic equations, would behave in a much clearer way (and more similar to the PLA, also based on equations) than EPROM (which is essentially a huge lookup table). Wasn't that a problem in the C64, too? Regards, Michau. Message was sent through the cbm-hackers mailing listReceived on 2013-03-26 16:01:26
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