User`s guide

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Operation Theory
4.4.2.3 Mode 3: Single Pulse-width Measurement
In this mode the counter counts the pulse-width of the signal on
GPTC_GATE in terms of GPTC_CLK. Initial count can be loaded from
software. 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 out-
puts high and then current count value can be read-back by software.
Figure 33 illustrates the operation where initial count = 0, count-up mode.
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Gate
CLK
Count value
Software start
Figure 33: Mode 3 Operation
4.4.2.4 Mode 4: Single Gated Pulse Generation
This mode generates a single pulse with programmable delay and pro-
grammable pulse-width following the software-start. The two programma-
ble parameters could be specified in terms of periods of the GPTC_CLK
input by software. GPTC_GATE is used to enable/disable counting. When
GPTC_GATE is inactive, the counter halts the current count value. Figure
34 illustrates the generation of a single pulse with a pulse delay of two and
a pulse-width of four.
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Gate
CLK
Count value
OUT
Software start
Figure 34: Mode 4 Operation