VXR-S Sun-HAL problem
John Harwood (jsh@samson.chem.uic.edu)
Wed, 2 Mar 94 09:46:24 -0800
AMMRL Members-
I recently had the following experience with our 1989
VXR-300S spectrometer (Sun 3/60). Since I have not used VXR
spectrometers much, I don't know if the following problem is
well known or not. In any case, I offer it for perusal.
Over the course of three months, the spectrometer
began hanging up more and more frequently, until it would not
run at all if Acqproc was running. The system would run fine
if Acqproc wasn't running, and access to tape and disk were
not affected. When Acqproc was running, the Sun would hang
and could only be recovered using the L1-a escape. Upon re-
boot, there were often messages displayed that mentioned the
SCSI interface. The HAL monitor showed no errors.
To make a long story short(er), we found a lot of
ripple on the 5V supply in the differential box. Our shop
replaced the 10000uF 16V capacitor with a 10000uF 50V unit
mounted off the power supply board, and the problem was
cured. The 50V capacitor is much larger physically, and is
supposed to be more reliable than the 16V cap.
Interestingly, running some checks on the communic-
ation from Sun to HAL also showed no problems.
If anyone would like to discuss this further, please
e-mail me.
John Harwood
jsh@samson.chem.uic.edu