By connecting BenchVue to the Power meter N1912A I can control the instrument but I can't use any of the tabs in the automatic Test Flow. Is it possible with N1912A ?
Unfortunately, none of the Power Meter functions are enabled for use with Test Flow. If you do not load the app, you can use the SCPI or Command Expert blocks to talk to the instrument yourself using SCPI commands.
Is there away to pass variable from test flow to the SCPI command so we can make a loop over frequency?
It is possible, though a little "clunky". Let's say on the first iteration you want to send the command "FREQ 1" to something, and on the second iteration you want to send "FREQ 2". You can set up a loop counter, and then use IF statements to create a new SCPI command. You could use the string function to concatenate a number with a header, like "FREQ " and "1.23E01", but you have to be careful - Test Flow will treat a pure number as numeric. It is hard to convince it that you want it to be a string. So in the example below, I just created a complete SCPI command, making it clear that it is a string. Then you can use that variable in the SCPI block as shown.
It is rather difficult to execute SCPI command for power meter inside the BenchVue.
I keep receiving message that "Application does not support execution of a SCPI command". It is seen from I/O monitor that real SCPI command wasn't send. There is no problem to send command via Interactive IO (please see attached photo). I see the same with USB connection to Power meter and with LAN connection.
You can't use the app AND Test Flow SCPI at the same time. Close the PM app and the SCPI will work. If you need to set up the instrument in some particular way first, use the state save/load feature to get it set up, then close the app, then run the Test Flow sequence.
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