9 Nov
2007
9 Nov
'07
2:17 p.m.
On 09/11/2007 18:22, M H Stein wrote:
Another problem I recall was that it's easy to damage the 6820s in a
PET, by plugging some user-port devices into the IEEE port or vice versa
(I can't remember which was more likely to upset things). We used to
fix it by replacing the damaged 6520 with a Motorola 6821, which is a
pin-compatible replacement, but seemed in practice to be more robust.
--
Pete Peter Turnbull
Network Manager
University of York
From: Ethan Dicks <ethan.dicks at usap.gov>
I got a lot of
miles out of that PET. I still have it and it still
fires up (but I think I have an IEEE problem that may turn out to be
cruddy 40-pin sockets on the VLSI I/O chips).
<snip>
Those sockets were indeed a PITA, but another easy-to-overlook problem
I ran into with my 8050 disk drive is that if you happen to catch the tip of
one of the contacts in the female IEEE connector while plugging in the cable
you can easily push it into the connector and out the back, causing an
intermittent.