Adjust Digital IO system frequency in Python API

[HarissonJones]

I know I can adjust the system frequency of the Digital IO in the WaveForms application from the Supplies tab.

I just can't figure out how to do this in the Python API.

I need to generate a signal frequency of 10.42MHz.

Could you show me how please? Thank you very much.

[attila]

Hi @Steve_3

In v3 one analog-out run is performed for each analog-in capture. Having FDwfAnalogOutRepeatTriggerSet-1 each analog-out run will wait for trigger (analog-out capture).
After each analog-in reading by the software (FDwfAnalogInStatus) a new capture is started which also initiates a new analog-out run.
This is why the analog-out repeat is set to infinite (FDwfAnalogOutRepeatSet-0).
Adding wait to analog-out would delay the signal relative to the analog-in start, shift the signal to the right in the capture.
To shift it left (or right), to start the analog-out before (or after) the capture left-most sample use a positive (or negative) secDelay parameter.

[Steve_3]

Thank you. Yes, I'm able to delay the acquisition and the pulse independently, and it maintains phase stability.  What i was attempting was to send out two RF sine wave bursts,  (say 1 ms each, seperated by 5 msec)  and then acquire.    I can delay the acquisition,   I just can't generate the second RF pulse (until there is a new acquisition).

It seems the analog repeat set must be infinite, but it waits for a new trigger.   Ordinarily, when triggering off of the PC, I can set this for any number and once it receives the trigger it fires the N bursts seperated by a specified delay.   With repeatSet set to infinite, it seems the delay between pulses is only set by waiting for the acquisition?   

 

[attila]

Hi @Steve_3

Here two periods are generated for each capture: test_undersampling_v4.py
Analog-in: trigger-wait-run-wait-run-done
I set the wait to 2ms to fit in the 8ms capture, but you can adjust the analog-in trigger position (secDelay) as you need it.

[Steve_3]

Fantastic.   I'll read and figure out what I needed to do,  looks like it was the RepeatTriggerSet I was missing.   Thanks from a newbie.