ATmega32U4 Atmel Corporation, ATmega32U4 Datasheet - Page 102

• Manufacturer Part Number: ATmega32U4
• Manufacturer: Atmel Corporation

Specifications of ATmega32U4

• Flash (kbytes): 32 Kbytes
• Pin Count: 44
• Max. Operating Frequency: 16 MHz
• Cpu: 8-bit AVR
• # Of Touch Channels: 14
• Hardware Qtouch Acquisition: No
• Max I/o Pins: 26
• Ext Interrupts: 13
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 2
• Twi (i2c): 1
• Uart: 1
• Graphic Lcd: No
• Video Decoder: No
• Camera Interface: No
• Adc Channels: 12
• Adc Resolution (bits): 10
• Adc Speed (ksps): 15
• Analog Comparators: 1
• Resistive Touch Screen: No
• Temp. Sensor: Yes
• Crypto Engine: No
• Sram (kbytes): 3.3
• Eeprom (bytes): 1024
• Self Program Memory: YES
• Dram Memory: No
• Nand Interface: No
• Picopower: No
• Temp. Range (deg C): -40 to 85
• I/o Supply Class: 2.7 to 5.5
• Operating Voltage (vcc): 2.7 to 5.5
• Fpu: No
• Mpu / Mmu: no / no
• Timers: 4
• Output Compare Channels: 12
• Input Capture Channels: 2
• Pwm Channels: 8
• 32khz Rtc: No
• Calibrated Rc Oscillator: Yes

13.8
13.8.1
7766F–AVR–11/10
8-bit Timer/Counter Register Description
Timer/Counter Control Register A – TCCR0A
• Bits 7:6 – COM01A:0: Compare Match Output A Mode
These bits control the Output Compare pin (OC0A) behavior. If one or both of the COM0A1:0
bits are set, the OC0A output overrides the normal port functionality of the I/O pin it is connected
to. However, note that the Data Direction Register (DDR) bit corresponding to the OC0A pin
must be set in order to enable the output driver.
When OC0A is connected to the pin, the function of the COM0A1:0 bits depends on the
WGM02:0 bit setting.
are set to a normal or CTC mode (non-PWM).
Table 13-2.
Table 13-3
mode.
Table 13-3.
Note:
Bit
Read/Write
Initial Value
COM0A1
COM0A1
0
0
1
1
0
0
1
1
1. A special case occurs when OCR0A equals TOP and COM0A1 is set. In this case, the Com-
pare Match is ignored, but the set or clear is done at TOP. See
for more details.
shows the COM0A1:0 bit functionality when the WGM01:0 bits are set to fast PWM
7
COM0A
1
R/W
0
Compare Output Mode, non-PWM Mode
Compare Output Mode, Fast PWM Mode
COM0A0
COM0A0
0
1
0
1
0
1
0
1
Table 13-2
6
COM0A
0
R/W
0
Description
Normal port operation, OC0A disconnected.
Toggle OC0A on Compare Match
Clear OC0A on Compare Match
Set OC0A on Compare Match
Description
Normal port operation, OC0A disconnected.
WGM02 = 0: Normal Port Operation, OC0A Disconnected.
WGM02 = 1: Toggle OC0A on Compare Match.
Clear OC0A on Compare Match, set OC0A at TOP
Set OC0A on Compare Match, clear OC0A at TOP
5
COM0B
1
R/W
0
shows the COM0A1:0 bit functionality when the WGM02:0 bits
4
COM0B
0
R/W
0
3
–
R
0
(1)
2
–
R
0
R/W
ATmega16/32U4
1
WGM0
1
0
“Fast PWM Mode” on page 97
0
WGM0
0
R/W
0
TCCR0A
102