09-06-2017 04:17 AM
I have a PXie-1073 chassis which has a PXI-6723 (NI-DAQmx) for analog output generation and a PXI-6541 (NI-HSDIO) for digital generation.
The PXI-6541 is configured to run in scripted mode and uses its digital start trigger to start the generation of the samples written to the 6723 card. After each card has finished its generation, the buffer is overwritten with a new one.
I would like to configure them such that if I want to repeat the same sequence, each card will regenerate its buffer. To do this, I have set the SampleQuantityMode property to ContinuousSamples and WriteRegenerationMode to AllowRegeneration for the 6723 card and modified the 6541 script to repeat forever
script myScript
repeat forever
generate data
end repeat
end myScript
The problem I've found is that the two sequences become de-synchronised. The two cards use their own sample clocks - the 6541 uses a 10 MHz clock referenced to the 10 MHz reference on the PXIe chassis, and the 6723 uses a 100 kHz clock which should also be referenced to this.
Is there a better way to synchronise the output of these cards and ensure that they remain synchronised after each loop?