94
8025I–AVR–02/09
ATmega48P/88P/168P/328P
12. 8-bit Timer/Counter0 with PWM
12.1
Features
•
Two Independent Output Compare Units
•
Double Buffered Output Compare Registers
•
Clear Timer on Compare Match (Auto Reload)
•
Glitch Free, Phase Correct Pulse Width Modulator (PWM)
•
Variable PWM Period
•
Frequency Generator
•
Three Independent Interrupt Sources (TOV0, OCF0A, and OCF0B)
12.2
Overview
Timer/Counter0 is a general purpose 8-bit Timer/Counter module, with two independent Output
Compare Units, and with PWM support. It allows accurate program execution timing (event man-
agement) and wave generation.
A simplified block diagram of the 8-bit Timer/Counter is shown in
. For the actual
placement of I/O pins, refer to
”Pinout ATmega48P/88P/168P/328P” on page 2
. CPU accessible
I/O Registers, including I/O bits and I/O pins, are shown in bold. The device-specific I/O Register
and bit locations are listed in the
”Register Description” on page 106
.
The PRTIM0 bit in
”Minimizing Power Consumption” on page 42
must be written to zero to
enable Timer/Counter0 module.