The following table lists the default input terminals for various counter measurements. You can use a different PFI line for any of the input terminals, with the exception of the count direction terminal for edge counting. To change the PFI input for a measurement, use the NI-DAQmx channel attributes/properties.

Measurement Ctr0 Ctr1
Count Edges
  • Edges: PFI 8
  • Count Direction[1]1 The count direction terminal must be tristated to use an external signal. Reset the device to ensure the terminal is tristated: port0/line6
  • Edges: PFI 3
  • Count Direction[1]: port0/line7
Pulse Width Measurement PFI 9 PFI 4
Period/Frequency Measurement (Low Frequency with One Counter) PFI 9 PFI 4
Period/Frequency Measurement (High Frequency with Two Counters) PFI 8 PFI 3
Period/Frequency Measurement (Large Range with Two Counters) PFI 8 PFI 3
Semiperiod Measurement PFI 9 PFI 4

The following table lists the default output terminals for counter output. You must use the default output terminal, with the exception that for Ctr0, you can select a RTSI line.

Ctr0 Ctr1
CTR 0 OUT CTR 1 OUT

1 The count direction terminal must be tristated to use an external signal. Reset the device to ensure the terminal is tristated