Generating an External Sample Clock on a USB 600x Series Card

Updated Jul 10, 2019

Reported In


  • USB-6001
  • USB-6002
  • USB-6003
  • USB-6008
  • USB-6009

Issue Details

Is it possible to set my DAQmx timing on a USB-600x series card to an external sample clock using the PFI lines?


No, the PFI lines on those cards only support digital counters and analog input/output start triggers. The clock will not accept external clock sources for data acquisition or generation.

Additional Information

The DAQmx API does not generate an error when wiring in an external clock to the DAQmx timing VI. Instead it defaults to the onboard clock sample rate.