27 Apr
2011
27 Apr
'11
7:49 a.m.
On Tue, Apr 26, 2011 at 7:34 PM, Michael Thompson
<michael.99.thompson at gmail.com> wrote:
We (RICM) have an 8/I with 5x TU55 drives, a pair of
bare 8/L, and a
very functional 8/S that now runs FOCAL.
Did you have to do any work on that -8/S? I have one that needs a lot
of replacement bulbs and some sleuthing in the "lock" circuit (the
switch is fine, but the machine behaves as if it's always in "lock"
mode). I've done lots of work on M-series machines like the -8/L and
-8/i (it's where I got my start with 12 bits), but virtually no
debugging of the older logic. I built a simple M-series FLIP-CHIP
tester with a DEC backplane socket and an 6821 PIA, but it was
straightforward to abstract different arrangements of inputs and
outputs for different modules. I haven't done the homework to see how
many types of R/S-series modules are used in a Straight-8 or -8/S, so
I'm not even sure how difficult it would be to make a comparable logic
tester. I'd like to automate the testing to the point where I could
at least plug in a suspect module and either flip some switches or
type some commands to exercise the inputs and monitor the outputs -
yes, one can debug pre-TTL machines with a lot of clip leads and an
oscilloscope, but I'd like to abstract that one level to see what
boards need detailed attention.
Has anyone ever considered building an automated or semi-automated
R/S-Series module tester? Did it get further than musings and
drawings?
-ethan