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FUJITSU F2MC-8L F202RA User Manual

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CHAPTER 8 8/16-BIT CAPTURE TIMER/COUNTER

Counter Function

The counter function counts the falling edges of the external clocks input to the P33/EC external pin. The 8/

16-bit capture timer/counter can operate independently because the EC pin acts as an external clock input

pin. Only timer 0 can select the external clock. The counter function operates using timer 0 with the 8-bit

mode or with the 16-bit mode.

The counter function counts the number of edges of the external clocks selected by the count clock

selection bit (CINV) of the timer 0 control register (TCR0). When the number of edges equals the

setting value, the counter function generates an interrupt request and inverts the output level of the

square wave output pin.

In timer 0 for the 8-bit mode, a count operation up to 2

8

is possible.

In the 16-bit mode, a count operation up to 2

16

is possible.

Inputting an external clock whose cycle is constant enables the counter to be used as a device whose

function is similar to an interval timer.

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