ATmega16U4 datasheet(72/408 Pages) ATMEL

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7766D–AVR–01/09

ATmega16U4/ATmega32U4

OC1B, Output Compare Match B output: The PB6 pin can serve as an external output for the

Timer/Counter1 Output Compare B. The pin has to be configured as an output (DDB6 set “one”)

to serve this function. The OC1B pin is also the output pin for the PWM mode timer function.

PCINT6, Pin Change Interrupt source 6: The PB7 pin can serve as an external interrupt source.

OC.4B: Timer 4 Output Compare B. This pin can be used to generate a high-speed PWM signal

from Timer 4 module. The pin has to be configured as an output (DDB6 set “one”) to serve this

function.

ADC13: Analog to Digital Converter, channel 13.

• OC1A/PCINT5/OC.4B/ADC12, Bit 5

OC1A, Output Compare Match A output: The PB5 pin can serve as an external output for the

Timer/Counter1 Output Compare A. The pin has to be configured as an output (DDB5 set (one))

to serve this function. The OC1A pin is also the output pin for the PWM mode timer function.

PCINT5, Pin Change Interrupt source 5: The PB7 pin can serve as an external interrupt source.

OC.4B: Timer 4 Output Compare B. This pin can be used to generate a high-speed PWM signal

from Timer 4 module, complementary to OC.4B (PB5) signal. The pin has to be configured as an

output (DDB5 set (one)) to serve this function.

ADC12: Analog to Digital Converter, channel 12.

• PCINT4/ADC11, Bit 4

PCINT4, Pin Change Interrupt source 4: The PB7 pin can serve as an external interrupt source.

ADC11, Analog to Digital Converter channel 11.

• PDO/MISO/PCINT3 – Port B, Bit 3

PDO, SPI Serial Programming Data Output. During Serial Program Downloading, this pin is

used as data output line for the ATmega16U4/ATmega32U4.

MISO: Master Data input, Slave Data output pin for SPI channel. When the SPI is enabled as a

master, this pin is configured as an input regardless of the setting of DDB3. When the SPI is

enabled as a slave, the data direction of this pin is controlled by DDB3. When the pin is forced to

be an input, the pull-up can still be controlled by the PORTB3 bit.

PCINT3, Pin Change Interrupt source 3: The PB7 pin can serve as an external interrupt source.

• PDI/MOSI/PCINT2 – Port B, Bit 2

PDI, SPI Serial Programming Data Input. During Serial Program Downloading, this pin is used

as data input line for the ATmega16U4/ATmega32U4.

MOSI: SPI Master Data output, Slave Data input for SPI channel. When the SPI is enabled as a

slave, this pin is configured as an input regardless of the setting of DDB2. When the SPI is

enabled as a master, the data direction of this pin is controlled by DDB2. When the pin is forced

to be an input, the pull-up can still be controlled by the PORTB2 bit.

PCINT2, Pin Change Interrupt source 2: The PB7 pin can serve as an external interrupt source.

• SCK/PCINT1 – Port B, Bit 1

SCK: Master Clock output, Slave Clock input pin for SPI channel. When the SPI is enabled as a

slave, this pin is configured as an input regardless of the setting of DDB1. When the SPI0 is

ATmega16U4 Datasheet(PDF) 72 Page - ATMEL Corporation