04-28-2020 09:21 AM - edited 04-28-2020 09:22 AM
Hi,
I keep loosing communication with an instrument randomly. Sometimes data acquisition works trouble free for days , sometimes for a couple of hours. After I've lost the communication i must restart both the PC and the instrument.
Can i force a specific COM port to restart run-time in labview? I am using an RS232 DB9 connector with shielded cable of length 1 meter.
Have you got any ideas how to solve this technical issue?
Kind regards,
Balázs
Solved! Go to Solution.
04-28-2020 09:43 AM
What do you mean by restarting the COM port? You can close it by calling VISA Close and then open/configure it again. Do you keep the port open all the time while the program is running? Any error when the communication is lost?
04-29-2020 07:40 AM - edited 04-29-2020 07:42 AM
Yes, opening and configuring it again does not help. Please visit this topic to see the errors.
https://forums.ni.com/t5/LabVIEW/Communication-stucks-with-Ketihley-2700-data-logger/td-p/4021341
04-29-2020 09:39 AM - edited 04-29-2020 09:40 AM
At any point does your program go into a idle state for a period of time? Are you using a serial to USB converter?
It would help us if you uploaded your VI too.
04-29-2020 10:16 AM
@LTBALAZS wrote:
After I've lost the communication i must restart both the PC and the instrument.
Yikes! Assuming that the SW is written correctly, this might indicate a ground loop or ESD problem. Or maybe a power problem? Have you try using a laptop?
Another thing to try is to throw away the Keithley supplied instrument drivers and code up your own.
BTW. It is very hard to troubleshoot intermittent problems like yours.
06-09-2020 02:03 AM
Hi, it was ground loop problem.