National Instruments AT-MIO-16X - Manual (Page 60)

Chapter 2 Configuration and Installation
AT-MIO-16X User Manual 2-38 © National Instruments Corporation
Figure 2-17. Event-Counting Application with External Switch Gating
To perform pulse-width measurement, a counter is programmed to be
level gated. The pulse to be measured is applied to the counter GATE
input. The counter is programmed to count while the signal at the GATE
input is either high or low. If the counter is programmed to count an
internal timebase, then the pulse width is equal to the counter value
multiplied by the timebase period.
For time-lapse measurement, a counter is programmed to be edge gated.
An edge is applied to the counter GATE input to start the counter. The
counter can be programmed to start counting after receiving either a
high-to-low edge or a low-to-high edge. If the counter is programmed
to count an internal timebase, then the time lapse since receiving the
edge is equal to the counter value multiplied by the timebase period.
4.7 k
Ω
Signal
Source
Switch
DIG GND
Counter
OUT
SOURCE
GATE
+5 V
I/O Connector
AT-MIO-16X Board