06-13-2013 02:20 PM
I try to generate 50 HZ pulse in USB 6210 with sample code "http://zone.ni.com/devzone/cda/epd/p/id/3088". But doesn't work properly.
Please see attachment:
app.jpg: pluses setting. I set 200000 ticks to low and high.
Tick count based.jpg : result wave from oscilloscope.
You will see low is 3 times longer than and high.
Do you have any idea?
Thanks.
06-16-2013 10:07 PM
pc@norpix.com,
Does this happen on ctr0 as well? Also, have you tried decreasing the low and high ticks to something more like 1000? I'd like to see if we can get the output to look as we expect. My last question is, what are you using for a trigger source? Have you tried this with a non-retriggerable example? If so, does it output the same incorrect waveform? Thanks for the pictures. Those are always helpful for visualizing the situation.
06-17-2013 07:54 AM
I didn't test ctr0 since It's used by something else.
Trigger source is standard TTL signal generated by NI PCI 6601;without trigger is the same.
06-18-2013 01:09 PM
pc@norpix.com,
Could you tell me more about the trigger signal you are using from your NI PCI 6601? Is it outputting at a particular frequency? My thought is that maybe we are retriggering before the waveform has finished a generating a complete period. It looks like there is one period that looks correct from the original picture you posted. Not to be too repetitive, but did reducing the ticks make the duty cycle correct?