16-Bit Timer/Counter1 With Pwm; Overview - Atmel AT90PWM2 Manual

15. 16-bit Timer/Counter1 with PWM

15.1

Overview

4317I–AVR–01/08
The 16-bit Timer/Counter unit allows accurate program execution timing (event management),
wave generation, and signal timing measurement. The main features are:
•
True 16-bit Design (i.e., Allows 16-bit PWM)
•
Two independent Output Compare Units
•
Double Buffered Output Compare Registers
•
One Input Capture Unit
•
Input Capture Noise Canceler
•
Clear Timer on Compare Match (Auto Reload)
•
Glitch-free, Phase Correct Pulse Width Modulator (PWM)
•
Variable PWM Period
•
Frequency Generator
•
External Event Counter
•
Four independent interrupt Sources (TOV1, OCF1A, OCF1B, and ICF1)
Most register and bit references in this section are written in general form. A lower case "n"
replaces the Timer/Counter number, and a lower case "x" replaces the Output Compare unit
channel. However, when using the register or bit defines in a program, the precise form must be
used, i.e., TCNT1 for accessing Timer/Counter1 counter value and so on.
A simplified block diagram of the 16-bit Timer/Counter is shown in
placement of I/O pins, refer to
including I/O bits and I/O pins, are shown in bold. The device-specific I/O Register and bit loca-
tions are listed in the "16-bit Timer/Counter Register Description" on page
The PRTIM1 bit in "Power Reduction Register" on page 43
Timer/Counter1 module.
"Pin Descriptions" on page
AT90PWM2/3/2B/3B
Figure 15-1. For the actual
5. CPU accessible I/O Registers,
123.
must be written to zero to enable
103