Using the acquisition channels as a trigger for generating pulses

[redpapaya]

Hi!

I'm new to working with the Red Pitaya and am currently having some issues with the trigger for the signal generator. I want to generate a signal from OUT1 based on a 10 Hz trigger-input on IN2.

I've tried the following however the time between input and output seems very large and not consistent (10-30 ms). Am I doing something wrong or is there another way of doing this?

Code: Select all

rp_s.tx_txt('GEN:RST')
rp_s.tx_txt('SOUR1:FUNC ARBITRARY')
rp_s.tx_txt('SOUR1:TRAC:DATA:DATA ' + waveform_ch_1)
rp_s.tx_txt('SOUR1:FREQ:FIX ' + str(freq))
rp_s.tx_txt('SOUR1:VOLT ' + str(Amp))
rp_s.tx_txt('SOUR1:BURS:STAT BURST')
rp_s.tx_txt('SOUR1:BURS:NCYC 1')
rp_s.tx_txt('SOUR1:BURS:NOR 1')
rp_s.tx_txt('OUTPUT1:STATE ON')
#rp_s.tx_txt('SOUR1:TRIG:INT')

rp_s.tx_txt('ACQ:RST')
rp_s.tx_txt('ACQ:DATA:FORMAT ASCII')
rp_s.tx_txt('ACQ:DATA:UNITS VOLTS')
rp_s.tx_txt('ACQ:DEC 1')
rp_s.tx_txt('ACQ:TRIG:LEV 0.5')
rp_s.tx_txt('ACQ:START')
rp_s.tx_txt('ACQ:TRIG CH2_PE')

t1_start = time.perf_counter()
while 1:
    rp_s.tx_txt('ACQ:TRIG:STAT?')
    if rp_s.rx_txt() == 'TD':
    	t1_stop = time.perf_counter()
    	print("Elapsed time between trigs:",(t1_stop-t1_start)) 

        # Trigger output
        rp_s.tx_txt('SOUR1:TRIG:INT')

        #Prepare ACQ
        rp_s.tx_txt('ACQ:START')
        rp_s.tx_txt('ACQ:TRIG CH2_PE')

        print('Trigger happened!')

    	t1_start = time.perf_counter()  

[redpitaya]

First of all, I would like to apologize for my late reply. We were representing Red Pitaya at Embedded World the previous week.


I would suggest you set up the generator to work on the External trigger from pin DIO0_P. Then you can trigger the generator at 10 Hz without issues (please use a 3V3 CMOS signal as the external trigger).
https://redpitaya.readthedocs.io/en/lat ... al-trigger


The SCPI commands have a network delay, and the Linux on Red Pitaya does not operate in real-time, so you will experience delays if you send a lot of SCPI commands.

If you want the program to run as fast as possible or be very precise, I would suggest making a C program that can run on Red Pitaya itself.

[redpapaya]

Thank you for the reply, and sorry for replying a bit late myself. I actually tried implementing the program in C afterwards as well however the results were still not to my liking. I've decided to go ahead with using the external trigger instead and it seems to work perfectly.

[redpitaya]

I am glad that the issue was resolved.

Good luck with your project.