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Generate single pulse on multiple channels from external trigger on High Speed DIO

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Hello,

 

I am attempting to set up a system using a PCIe-6535B connected to a SMB-2163 high speed DIO.  The system needs to be set up to work with a camera sending a trigger (at the start of each exposure) to PFI4 which in turn sends a single pulse out  three digital output channels to lasers.  Each digital output has its own specific delay and width.  There are no counters on the SMB-2163 so I think I need to use Pulse Width Modulation (PWM).  I saw this example and adapted it to my system:

 

https://decibel.ni.com/content/docs/DOC-8010

 

However, when the source going into the DAQmx Sample Clock VI is set to PFI4 (instead of the onboard clock)  to receive the input from the camera, the behavior changes.  The Sample Rate going into the Sample Clock VI is ignored and instead each element of the digital waveform is triggered.  I need the entire sequence to complete after each trigger.

 

I have attached a quick schematic of the timing sequence.  Any suggestions on how I can achieve this type of triggered event? (Using LabVIEW 2013)

 

Thanks,

 

Mike

 

CLAD

 

 

Timing_Sequence.png

PWM_Attempt.PNG

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Accepted by topic author mpstocker

The external signal should be configured as a digital start trigger rather than the sample clock.  I don't believe the 6535 supports retriggerable digital output, so you'll have to restart the task after each trigger is received (something like this, though you can improve performance by committing the task using DAQmx Control Task  before entering the loop).

 

 

Best Regards,

John Passiak
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John_P1,

 

Great, thanks!  I've attached my modified version for reference.

 

Best,

 

Mike

 

CLAD

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