ADLINK Technology USB-1901, User Manual

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Operation 59
USB-1900 Series
4.8.2 Mode 2: Single Period Measurement
The counter calculates the period of the signal on GPTC_GATE in
terms of GPTC_CLK. The initial count can be loaded from the soft-
ware application. After software start, the counter calculates 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 by the software application. Operation in which
initial count = 0, count-up mode is shown.
Figure 4-19: Mode 2-Single Period Measurement
4.8.3 Mode 3: Single Pulse-Width Measurement
The counter calculates the pulse-width of the signal on
GPTC_GATE in terms of GPTC_CLK. Initial count can be loaded
from the software application. After software start, the counter cal-
culates 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 current count value can be read by
the software application. Operation in which initial count = 0,
count-up mode is shown.
0 0 1 2 3 4 5 5 5
Gate
CLK
Count value
Software start