03-14-2012 07:52 AM
Hello,
i have just updated ni daqmx, now i have daqmx 9.3
Problem is not solved
I test timers with Rubidium precise oscillator and PPS output:
1st counter source: 1 MHz from rubidium
1st counter trigger: pause when counter 2 is low
2nd counter source: 1 PPS
Multiple pulse generation works fine! if i configure one counter to generate two 50-second pulses and trigger other counter with it, the last one indicates exactly 100.000.000 loops (1 MHz source * 100s)
but the problem with 1 pulse generation is still actual:
high ticks=5 => 4.008.011 pulses counted
high ticks=100 =>99.007.899 pulses counted
i post the test program which i used
i will try to control 1st timer with start trigger and stop it with connecting gate input to ctr2output, trigger pause function may be bugged.
Probably it is the software bug, unfortunately i cannot update labview 8.5 right now, it would be very nice if some one test the attached application with the labview 2011, 2012
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Regards,
Alexander
03-15-2012 01:45 PM
Hey Alexander,
I got a PXI version of this 6602 and have hooked it up. I was having some issues with the code you provided, so I switched to purely using some of the examples inside of LabVIEW. I think these examples are available still in LabVIEW 8.5, but I'm not sure. I used the Generate Dig Pulse - Dig Start vi. Basically this configures a counter ouput instead of ticks to use pulse time. I'm not seeing any problems with it.
Are you able to try out the pulse time instead of ticks? Although if it's a software bug, this could still be part of the bug. I didn't notice any unexpected behavior over here though using Daqmx 9.3.5 with LabVIEW 2010. I have been looking over your screenshots though, and things appear to be configured correctly, and I see the behavior on your screenshots.
03-15-2012 02:34 PM
03-16-2012 08:20 AM
Alexander,
I'm glad to hear that things are working with the time option. If you have any issues with this with the upgraded software, please post again. Have a good day!
03-19-2012 06:32 AM
Hi All, The solution was found!
now i can generate any number of pulses,
the problem was with generating pulse from PPS timebase.
Experiment 1:
ctr0 [Source of ticks = PPS signal, high ticks = 10] => ctr0out-ctr2gate => ctr2 [Source 5 MHz rubidium]
Result: 45 038 014 counted
Experiment 2:
ctr0 [Source of ticks = 1 MHz rubidium, high ticks = 10 000 000] => ctr0out-ctr2gate => ctr2 [Source 5 MHz rubidium]
result: 50 000 000 counted
The same program was used for both experiments.
I dont know why, but pci-6602 cannot works properly with low frequency timebase (source ticks), but it counts PPS pulses perfectly.
I will use PPS signal for starting counters only, using PPS for puls generating results an error!
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Alexander.