RE: 264 Series and their chips

We made the original 7501/8501 with a 6510 and a 74ls74 on a small tower,
there wasn't a dependency on the excat mapping of the I/O p[ort at the
time, but should be something you can put together.

Bil Herd

-----Original Message-----
From: owner-cbm-hackers@musoftware.de
[mailto:owner-cbm-hackers@musoftware.de] On Behalf Of Ruud@Baltissen.org
Sent: Saturday, August 13, 2011 12:23 PM
To: cbm-hackers@musoftware.de
Subject: Re: 264 Series and their chips

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.

Just my two cents...


--
    ___
   / __|__
  / /  |_/     Groetjes, Ruud Baltissen
  \ \__|_\
   \___|       http://Ruud.C64.org







       Message was sent through the cbm-hackers mailing list

       Message was sent through the cbm-hackers mailing list