JYTEK NuDAQ PCI-69222, User Manual

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Operation Theory 51
Mode 2: Single Period Measurement
The counter counts the period of the signal on GPTC_GATE in
terms of GPTC_CLK. Initial count can be loaded from the
software application. After the software-start, the counter
counts the number of active edges on GPTC_CLK between
two active edges of GPTC_GATE. After the completion of the
period interval on GPTC_GATE, GPTC_OUT outputs high and
then current count value can be read-back by the software
application. Figure 4-19 illustrates the operation where initial count
= 0, count-up mode.
Figure 4-19: Mode 2 Operation
Mode 3: Single Pulse-width Measurement
The counter counts the pulse-width of the signal on
GPTC_GATE in terms of GPTC_CLK. Initial count can be
loaded from the software application.
After the software-start, the counter counts the number of
active edges on GPTC_CLK when GPTC_GATE is in its active
state.
After the completion of the pulse-width interval on
GPTC_GATE, GPTC_OUT outputs high and then current count
value can be read-back by the software application. Figure 4-20
illustrates the operation where initial count = 0, count-up mode.