Granville-Phillips VG-307 vs GPIB

[wbrown@csg.lbl.gov (Bill Brown)]

Is there anyone on the list(s) who has any experience using the VG_307 with
the GPIB interface?  I've been going 'round and 'round with these things for
several days.

They seems that the initially work ok but after a while
	(a-few-minutes <= a-while <= a_few_hours)
they stop responding.

Cycling power on the controller brings it "back-to-life."  Re-booting the
processor usually brings it "back-to-life."
	
We're using the N.I. GPIB-1014 vme interface, and the normal EPICS driver
& device support.  We're looking at 3 parameters in each controller and are
doing record-processing every 5 seconds.  There is only one vacuum gauge in
each unit, and I'm only trying to talk to one gauge at each address.

In my test setup there are no ion-gauges attached, but that doesn't seem to matter.

I've tried a lot of things - long GPIB cables, short GPIB cables, one instrument
on a "chain", two instruments on a "chain", different instruments, different
'1014, different processors, different vme bins, etc. with essentially the same
results.  Eventually the instrument seems to drop into "sulk mode" and I start
seeing nothing but timeouts.

I'd be most grateful for any hints or bits (bytes? shorts? longs?) of wisdom.


Disclaimer:  Any opinions are my own and have	    |
    nothing to do with the official policy or the   |  -bill
    management of L.B.L, who probably couldn't      |   wlbrown@lbl.gov
    care less about employees who play with trains. |