6 Apr
2010
6 Apr
'10
12:59 p.m.
On Tue, Apr 6, 2010 at 3:03 PM, Tony Duell <ard at p850ug1.demon.co.uk> wrote:
Agreed. I have a 2001N/3032 board that mostly works, except for the
IEEE port. It's not the drivers - I'm reasonably certain that it's a
PIA or VIA socket. I have recently secured a stack of 40-pin sockets
and replace them when I have the time. I've had this machine since it
was new, so I'm not unhappy to have to do so. I've gotten a lot of
milage out of it.
-ethan
I seem to rememebr (and it's been years since
I've been inside a PET)
that the scanning is doen by an output port on a PIA chip, decoded with a
TTL decoder.
Yes. A 74LS145.
Anyone have
knowledge of a known failure mode of this sort with these machines?
Many faults on PETs are caused by the very poor IC sockets used.
Replacing them all with turned pin ones will cure said faults, and even
if it doens't help now, (a) it will prevent such faults in th future and
(b) it will tell you that you have a real fault to find.