User's Manual

Chapter 2 Function Reference — SCXI_Set_Threshold
© National Instruments Corporation 2-365 NI-DAQ FRM for PC Compatibles
triggers low. The SCXI-1126 module uses the square wave to produce a corresponding
voltage that is proportional to the frequency of the original input signal.
The threshold values determines which part of the input signal to count, and which part to
ignore. For example, a large hysteresis setting will keep signal noise from adding to the
frequency of a signal. A small hysteresis and a properly chosen value for level will enable
the SCXI-1126 to count almost every part of the input signal.