Dave asks:
> This has been going on intermittently for a week. Also, it sometimes
> prints garbage characters (mostly strings of a dozen or so @) that are
> NOT in the spoolfiles. First noticed this soon after a couple power
> failures. The other most suspicious thing I can think of is that some
> new equipment was put in nearby about that time (a copier & a PC, etc).
> The data is not bad. When we startspool again, it normally prints ok.
> No garbage characters when I view the spoolfiles.
> System settings have not been changed.
> The printer guy replaced the main board, i/o board & logic board, and
> says that is all there is... It worked several hours after that, the
> longest it has worked since it started. Once we had a couple hours of
> failing several times a hour.
> Termdsm says the dtc & port are good. No other serial devices are
> misbehaving. Tried swapping another dtc-port/ldev/device-class, but it
> didn't help.
Given everything that you've written, I'd strongly suspect something like the
power supply in the DTC. LLIO errors are generally communication errors
between the HP3000 and a failing DTC. Quite similarly, garbage printed out
onto the printers suggest much the same point of failure.
If you remember, just a week ago the best minds on the list wrote that
software always acts deterministically. If you want to find intermittent
failures, you have to look at the analog world that lives just below the
digital one -- and power supplies are the foundation of that world.
Other possibilities are as well: bad grounding, perhaps due to a cut wire,
poor wiring, overloaded circuits, etc, anything that would impose a hum into
the communications circuit, especially based on whether other equipment was
turned on or off in the region of the DTC.
Question: Why do so many electronic devices hum?
Answer: Because they're too dumb to remember the words.
Wirt Atmar
* To join/leave the list, search archives, change list settings, *
* etc., please visit http://raven.utc.edu/archives/hp3000-l.html *
|
