I have a PXI-6541 card that I am using to trigger output on a PXIe-6341, using the nihsdio c# wrapper. The 6541 card is configured to be software-triggered and sends a start trigger from PFI0. To test the timing between the two cards, each card outputs a digital pulse on one channel 1ms after the start of the sequence. What I've found is that the 6341 card starts the pulse exactly 1ms after the trigger, but the 6541 card has a fixed delay of around 300us with a sample clock if 100 kHz. This delay increases by a factor of 10 when I reduce the clock frequency by a factor of 10, which makes me suspect it involves the number of clock cycles. The sample clock from the 6541 card, which is derived from its onboard clock, is routed to the 6341 card. I have checked the sequence that is being written to each card and the channel goes high at the same sample index. Is there a way to output a trigger after I call the Initiate() method to see when the sequence starts on the 6541 card or a better way to ensure both cards are triggered at the same time?
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