PIC Microcontroller Timer Basics

PIC Microcontroller: Timer Basics PIC18F4550 has four timers.

Timer0:

• Timer0 can work as Timer/Counter in both 8-bit and 16-bit modes
• Count registers: TMR0 and TMR1
• Timer control Register T0CON
• Timer flag bit TNR0IF

Timer1:

• Timer1 can work as a 16-bit timer or counter
• Count registers: TMR1H and TMR1L
• Timer control Register T1CON
• Timer flag bit TNR1IF
• Timer1 can be multiplexed with other peripherals like ADC etc. and generates special event triggering for CCP (Capture, Compare and PWM) events.

Timer2:

• 8-bit Timer
• Timer and Period registers: TMR2 and PR2, respectively
• Software programmable prescaler (1:1, 1:4 and 1:16)
• Software programmable postscaler (1:1 - 1:16)
• Timer Flag bit TMR2IF
• Optional use as the shift clock for the MSSP (Master Synchronous Serial Port) module

Timer3:

• Timer3 can work as a 16-bit timer or counter
• Timer count registers TMR3H and TMR3L
• Flag bit TMR3IF
• Timer3 can be multiplexed with other peripherals like ADC etc. and generates special event triggering for CCP (Capture, Compare, and PWM) events.