On 08/13/2011 06:23 PM, Ruud@Baltissen.org wrote: > Hallo Gerrit, > > > Have you ever thought about replacing the 8501 with a 8502 from a > C128? So far I found four differences: > - the 8501 has this MUX input (or output? I have no idea what it > does) which the C128 lacks > - the 8502 has an "extra" NMI input compared to the 8501 > - the 8501 lacks the P5 I/O pin, the 8502 P7 > - pinout doesn't match > If the MUX gate doesn't spoil things, what about using the 8502? > Regarding P5/P7: you either don't use the cassette recorder anymore > or adjust the bits of the Kernal. Haven't tried that yet, but the 8502 isn't an easy to find IC and I don't want to take spare parts away from the C128 users. From what I read, you'd have to rebuild the GATE_IN logic by hand since leaving that pin unused on a 8501 screws up memory now and then. Gerrit Message was sent through the cbm-hackers mailing listReceived on 2011-08-13 18:00:07
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