Main INDEX,
Monthly INDEX,
PREV,
NEXT
Make New Entry,
Make Followup Entry
User name jmaxwell
Log entry time 13:34:46 on March 01, 2009
Entry number 177909
This entry is a followup to: 177903
keyword=Target: Computer Trouble
It seems Narbe and Jonathan have resolved the computer issues, but I'll
address them in case it comes up again.
If PDP is unable to start certain modules, as they saw as green (OK)
messages from PDP like "Logger Started" due to other modules hanging,
this is almost always due to GPIB communication error. There are 2 GPIB
interfaces that the NMR computer uses: one is a physical board in the PC
(which talks to the RF generator and the frequency counter), the other is
a NI GPIB-ENET ethernet controller which is on the lower target platform
(which talks to the magnet PS, the He4 Manometer, the Lakeshore, etc).
The best thing to look at when you are worried about communications
errors is the NI Measurement and Automation Explorer (there's a link to
it on the desktop). This lists all the devices and they're status. If
an error comes back like they saw (data connection error), you'll
probably need to restart the GPIB interfaces (which they did to fix the
problem).
It may also have been possible to reinitialize the network connection to
the ENET GPIB controller via the GPIB explorer. This could have
prevented the need for a hall access (but it seems hall access was
necessary for the run valve anyway). If the GPIB explorer doesn't work,
then reboot all the GPIB interfaces.
To reboot the first GPIB controller is easy, you just restart the
computer; the second requires hall access to unplug and replug the little
ENET device in Rack B of the lower platform. I don't expect this to
happen again, but the next time we're in the hall, I'll try to find an
extension cord to plug that ENET controller in to the hcreboot16 switch
in the SOS hut to allow remote rebooting.
Since the GPIB ENET is connected by the network, also consider resetting
the Hall C switch if GPIB is not working.