6 Oct
2005
6 Oct
'05
6:25 p.m.
From: ard at p850ug1.demon.co.uk
Hi
I've seen this done for pinball machines. There are some
potential issues other than just mapping the ROM. Some of
the internal selects are also mask programmed ( usually different
than the 6530 ). As I recall, one can even invert the data
going to the port( a real pain to handle ). I think there
is a document on the web someplace on making this patch.
Ahh, here it is. Look at:
http://www.6502.org/oldmicro/buildkim/buildkim.htm
later
Dwight
fear it's more likely a 6530, and I assume
they're unobtanium. Has
anyone ever come up with a kludge to effectively use a 6532 (and are
they any easier to find?) with an EPROM? Or anything else?
My Commodore 8250LP disk drive has an official kludgeboard in what seems
to be a socket designed for an 6530. It contains a 6532, a ROM, and a
simple TTL chip ('04 or something like that).
IIRC, though, the chip select levels of the 6530 were mask-programmable,
so this might not work in all cases. And I don't think I can get any
details of this to you by tomorrow anyway.