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Bit timer/counter1, Overview, Atmega8515(l) – Rainbow Electronics ATmega8515L User Manual

Page 94

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94

ATmega8515(L)

2512A–AVR–04/02

16-bit
Timer/Counter1

The 16-bit Timer/Counter unit allows accurate program execution timing (event man-
agement), 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)

Overview

Most register and bit references in this document 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. The physical I/O register and bit locations for ATmega8515 are listed in the
“16-bit Timer/Counter Register Description” on page 116.

A simplified block diagram of the 16-bit Timer/Counter is shown in Figure 46. CPU
accessible I/O registers, including I/O bits and I/O pins, are shown in bold.