Atmel ATmega48PV User Manual

162
8025I–AVR–02/09
ATmega48P/88P/168P/328P
If external pin modes are used for the Timer/Counter0, transitions on the T0 pin will clock the
counter even if the pin is configured as an output. This feature allows software control of the
counting.
15.11.3 TCNT2 – Timer/Counter Register
The Timer/Counter Register gives direct access, both for read and write operations, to the
Timer/Counter unit 8-bit counter. Writing to the TCNT2 Register blocks (removes) the Compare
Match on the following timer clock. Modifying the counter (TCNT2) while the counter is running,
introduces a risk of missing a Compare Match between TCNT2 and the OCR2x Registers.
15.11.4 OCR2A – Output Compare Register A
The Output Compare Register A contains an 8-bit value that is continuously compared with the
counter value (TCNT2). A match can be used to generate an Output Compare interrupt, or to
generate a waveform output on the OC2A pin.
15.11.5 OCR2B – Output Compare Register B
The Output Compare Register B contains an 8-bit value that is continuously compared with the
counter value (TCNT2). A match can be used to generate an Output Compare interrupt, or to
generate a waveform output on the OC2B pin.
Table 15-9. Clock Select Bit Description
CS22 CS21 CS20 Description
0 0 0 No clock source (Timer/Counter stopped).
001clk
T2S
/(No prescaling)
010clk
T2S
/8 (From prescaler)
011clk
T2S
/32 (From prescaler)
100clk
T2S
/64 (From prescaler)
101clk
T2S
/128 (From prescaler)
110clk
T
2
S
/256 (From prescaler)
111clk
T
2
S
/1024 (From prescaler)
Bit 76543210
(0xB2) TCNT2[7:0] TCNT2
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value 0 0 0 0 0 0 0 0
Bit 76543210
(0xB3) OCR2A[7:0] OCR2A
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value 0 0 0 0 0 0 0 0
Bit 76543210
(0xB4) OCR2B[7:0] OCR2B
Read/Write R/W R/W R/W R/W R/W R/W R/W R/W
Initial Value 0 0 0 0 0 0 0 0

Atmel ATmega48PV Specifications

General

Brand	Atmel
Model	ATmega48PV
Category	Microcontrollers
Language	English