attiny25v ATMEL Corporation, attiny25v Datasheet - Page 67

• Manufacturer Part Number: attiny25v
• Description: Microcontroller With 2/4/8k Bytes In-system Programmable Flash
• Manufacturer: ATMEL Corporation

11. 8-bit Timer/Counter0 with PWM
11.1
11.2
2586K–AVR–01/08
Features
Overview
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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
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
Figure 11-1. 8-bit Timer/Counter Block Diagram
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)
Timer/Counter
TCCRnA
OCRnA
TCNTn
OCRnB
=
=
“Register Description” on page
“Pinout ATtiny25/45/85” on page
Direction
Count
Clear
Control Logic
TOP
=
TCCRnB
Value
BOTTOM
Fixed
TOP
clk
80.
=
Tn
0
2. CPU accessible I/O Registers,
OCnA
(Int.Req.)
OCnB
(Int.Req.)
TOVn
(Int.Req.)
Clock Select
ATtiny25/45/85
Figure
Generation
Generation
Waveform
Waveform
( From Prescaler )
Detector
Edge
11-1. For the actual
OCnA
OCnB
Tn
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