Determine if Acquisition Complete on Pico 9000

[tim_hochberg]

Hi,

I'm controlling a Pico 9201 using COM and I'm wondering if there is any way to query the scope to determine if it has finished acquiring data. Specifically, when I use averaging on the scope, if I acquire new data without waiting for a sufficient time, I get incorrect results. I'm controlling the source of the waveform I'm measuring from the same program, so I update the source, clear the scope, wait for a while, then grab the data from the scope. Essentially:

# change the source
comobj.ExecCommand("*ClrDispl")
sleep(delta_t)
waveform_data = comobj.ExecCommand(":wf:data?")
# do something with the waveform data

If I choose delta_t correctly, then this works fine. However if delta_t is chosen to be too small, `waveform_data` will be incorrect. I suspect that I need to wait till the scope has finished acquiring it's first full set of averaged data. However, I haven't been able to find a query in the Picoscope 9000 programmers guide that will let me find this information. Does anyone know of any way to determine it?

Thanks in advance.

[Karunen]

Hi Tim,

You can do this by calling

Code: Select all

comobj.ExecCommand("*STOPSINGLE SINGLE") 

This will only call a single acquisition.

Then you can call

Code: Select all

comobj.ExecCommand("*STOPSINGLE?") 

Which will return "STOP" if the acquisition is finished.
Otherwise it will return "SINGLE"

Kind Regards,

[tim_hochberg]

Thanks Karunen, that seems to work perfectly.