7 Oct
2005
7 Oct
'05
6:40 p.m.
From: ard at p850ug1.demon.co.uk
Hi Tony
This is not totally true. I don't recall just what
it was but there are some mask options that are not easily
handled from the outside of the part. I just don't
recall what it was. I was looking at doing something
similar rather than pay about $120 to replace a sound
board on my Gottlieb Genie pinball machine.
As I recall it was an inversion of one of the data port's
outputs as a mask option or something like that.
Dwight
On Oct 6 2005, 22:03, Tony Duell wrote:
Argh, I misremembered it :-(. I've found the schematic I traced out. It
contains a 6530 (not a 6532), a 2716, and a 74LS04.
The 6530 pins are wirrd to corresponding pins on the header, apart from
RS0/, which is tied high (to disable the internal ROM of that chip). The
2716 A0..A9 go to the corresponding header pins, A10 is grounded. D0..D7
on the 2716 also go to the obvious header pins. OE/ goes to RS0/ on the
header. CS/ is Phi_2, inverted by one of the gates in the '04.
I don;t know if you could do a similar thing with a 6532, I think you
could. At least this would let you use any 6530 with the appropriate
chip-select polarites, no matter what was in the ROM. > 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
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).
Sounds like a start. I obviously can't get this fixed for, er, today,