01-21-2011 09:19 AM
Is there any way to delay the VISA open until it's the time to send out connection command to target via VISA write?
My current project has around 15 seconds time delay between VISA Open and UUT power up to send "connect" command via VISA write.
If UUT is not powered-on when VISA open, it will generate error 0xBFFF0072 (resource is valid, but VISA can't currently access it) and serial port can't be connected anymore.
I'm wondering if there is some way I can configure the time for VISA Open operation because I don't want to use time delay.
Thanks,
01-21-2011 12:49 PM
01-24-2011 10:28 AM
I'm implementing a custom device for NI VeriStand. VISA Open and VISA Configuration starts to run once the RT Driver runs. While VISA Write is controlled by WorkSpace which is launched 15 seconds later than the RT Driver runs. The UUT needs to be powered on before VISA Open, otherwise, error 0xBFFF0072 will occur. But if UUT is powered on before VISA Open, VISA Write will fail due to our 5 second delay protocol.
01-24-2011 02:36 PM
01-24-2011 03:35 PM
Thank you for your help. I fixed the problem.
01-24-2011 03:59 PM
01-24-2011 04:18 PM
I bet it's pretty simple for others. I just walked into a dead corner and couldn't think of anything else.
I used a while loop to wait for "Connection" command to be available from WorkSpace input. Once it's available, power up the UUT and start to VISA open and configuration operation.