User`s guide

Operation Theory

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4.4.2.1 Mode1: Simple Gated-Event Counting

In this mode, the counter counts the number of pulses on the GPTC_CLK

after the software-start. Initial count can be loaded from software. Current

count value can be read-back by software any time without affecting the

counting. GPTC_GATE is used to enable/disable counting. When

GPTC_GATE is inactive, the counter halts the current count value. Figure

31 illustrates the operation with initial count = 5, count-down mode.

55 432110ffff

Gate

CLK

Count value

Software start

Figure 31: Mode 1 Operation

4.4.2.2 Mode2: Single Period Measurement

In this mode, the counter counts the period 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 between two active edges of GPTC_GATE. After the com-

pletion of the period interval on GPTC_GATE, GPTC_OUT outputs high

and then current count value can be read-back by software. Figure 32 il-

lustrates the operation where initial count = 0, count-up mode.

00 1234555

Gate

CLK

Count value

Software start

Figure 32: Mode 2 Operation