ATMEGA64-16AI Atmel, ATMEGA64-16AI Datasheet - Page 159

• Manufacturer Part Number: ATMEGA64-16AI
• Description: IC AVR MCU 64K 16MHZ IND 64-TQFP
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA64-16AI

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 64KB (32K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 2K x 8
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 64-TQFP, 64-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

TCNT2 –
Timer/Counter
Register
2490Q–AVR–06/10
Table 67. Compare Output Mode, Phase Correct PWM Mode
Note:
• Bit 2:0 – CS22:0: Clock Select
The three Clock Select bits select the clock source to be used by the Timer/Counter.
Table 68. Clock Select Bit Description
If external pin modes are used for the Timer/Counter2, transitions on the T2 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 OCR2 Register.
Bit
0x24 (0x44)
Read/Write
Initial Value
COM21
CS22
0
0
0
0
1
1
1
1
0
0
1
1
1. A special case occurs when OCR2 equals TOP and COM21 is set. In this case, the Compare
COM20
CS21
Match is ignored, but the set or clear is done at TOP. See
153
0
0
1
1
0
0
1
1
0
1
0
1
R/W
for more details.
7
0
CS20
Description
Normal port operation, OC2 disconnected.
Reserved
Clear OC2 on Compare Match when up-counting. Set OC2 on Compare
Match when downcounting.
Set OC2 on Compare Match when up-counting. Clear OC2 on Compare
Match when downcounting.
0
1
0
1
0
1
0
1
R/W
6
0
Description
No clock source (Timer/counter stopped).
clk
clk
clk
clk
clk
External clock source on T2 pin. Clock on falling edge.
External clock source on T2 pin. Clock on rising edge.
R/W
I/O
I/O
I/O
I/O
I/O
5
0
/(No prescaling)
/8 (From prescaler)
/64 (From prescaler)
/256 (From prescaler)
/1024 (From prescaler)
R/W
4
0
TCNT2[7:0]
R/W
3
0
R/W
2
0
(1)
“Phase Correct PWM Mode” on page
R/W
1
0
ATmega64(L)
R/W
0
0
TCNT2
159