Appendix A Device-Specific Information
© National Instruments Corporation A-75 M Series User Manual
Note For more information about default NI-DAQmx counter inputs, refer to Connecting
Counter Signals in the NI-DAQmx Help or the LabVIEW Help in version 8.0 or later.
Connecting Signals to the USB-6251 BNC
Analog Input
You can use each analog input BNC connector for one differential signal or
two single-ended signals.
Differential Signals
To connect differential signals, determine the type of signal source you are
using—a floating signal (FS) source or a ground-referenced signal (GS)
source. Refer to the Connecting Analog Input Signals section of Chapter 4,
Analog Input, for more information.
Table A-16. Default NI-DAQmx Counter/Timer Pins
Counter/Timer Signal Default Pin Name
CTR 0 SRC PFI 8
CTR 0 GATE PFI 9
CTR 0 AUX PFI 10
CTR 0 OUT PFI 12
CTR 0 A PFI 8
CTR 0 Z PFI 9
CTR 0 B PFI 10
CTR 1 SRC PFI 3
CTR 1 GATE PFI 4
CTR 1 AUX PFI 11
CTR 1 OUT PFI 13
CTR 1 A PFI 3
CTR 1 Z PFI 4
CTR 1 B PFI 11
FREQ OUT PFI 14