A000047 Arduino, A000047 Datasheet - Page 191

• Manufacturer Part Number: A000047
• Description: MCU, MPU & DSP Development Tools Mega2560
• Manufacturer: Arduino
• Series: -r
• Type: MCUr

Specifications of A000047

• Processor To Be Evaluated: ATmega2560
• Interface Type: USB, I2C, SPI
• Dimensions: 4 in x 2.1 in
• Operating Supply Voltage: 5 V
• Contents: Board
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: ATmega2560

19.10.3
19.10.4
19.10.5
2549M–AVR–09/10
TCNT2 – Timer/Counter Register
OCR2A – Output Compare Register A
OCR2B – Output Compare Register B
Table 19-9.
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.
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.
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.
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.
Bit
(0xB2)
Read/Write
Initial Value
Bit
(0xB3)
Read/Write
Initial Value
Bit
(0xB4)
Read/Write
Initial Value
CS22
0
0
0
0
1
1
1
1
Clock Select Bit Description
R/W
R/W
R/W
7
0
7
0
7
0
CS21
0
0
1
1
0
0
1
1
R/W
R/W
R/W
6
0
6
0
6
0
ATmega640/1280/1281/2560/2561
CS20
R/W
R/W
R/W
0
1
0
1
0
1
0
1
5
0
5
0
5
0
R/W
R/W
R/W
4
0
4
0
4
0
OCR2A[7:0]
OCR2B[7:0]
TCNT2[7:0]
No clock source (Timer/Counter stopped).
R/W
R/W
R/W
3
0
3
0
3
0
clk
clk
clk
clk
clk
clk
T
T2S
clk
T
2
T2S
T2S
2
T2S
S
S
/1024 (From prescaler)
R/W
R/W
R/W
T2S
/256 (From prescaler)
/128 (From prescaler)
2
0
2
0
2
0
/32 (From prescaler)
/64 (From prescaler)
/8 (From prescaler)
Description
/(No prescaling)
R/W
R/W
R/W
1
0
1
0
1
0
R/W
R/W
R/W
0
0
0
0
0
0
OCR2A
OCR2B
TCNT2
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