Page 9 - DEC40053 Ebook_Timer

What is Timer?

Timers in microcontrollers are used for

introducing delay, counting events, generating

waveforms, and also PWM generation.

There are 4 timers that can be selected to use in

PIC18F

Timer0 (TMR0): 16-bit

Timer1 (TMR1) : 16-bit

Timer2 (TMR2) : 8-bit

Timer3 (TMR3) : 16-bit

The timer can be used either::

1. As timers generate a time delay

2. As counters to count events happening

outside the microcontroller.

Every timer needs a clock pulse to tick.

It is used to count clock signals coming into it.

Source of the clock signal:

1. From pins OSC1 and OSC2 or

2. Pin RA4/T0CKI or

3. Pin RC0/T10S0/T1CKI

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