ATXMEGA256A3BU Datasheet, PDF (55/143 Pages) ATMEL Corporation – 8/16-bit Atmel XMEGA A3BUMicrocontroller

33. Pinout and Pin Functions
The device pinout is shown in “Pinout/Block Diagram” on page 3. In addition to general purpose I/O functionality, each
pin can have several alternate functions. This will depend on which peripheral is enabled and connected to the actual pin.
Only one of the pin functions can be used at time.
33.1 Alternate Pin Function Description
The tables below show the notation for all pin functions available and describe its function.
33.1.1 Operation/Power Supply
V_CC
AV_CC
VBAT
GND
Digital supply voltage
Analog supply voltage
Battery Backup Module supply voltage
Ground
33.1.2 Port Interrupt functions
SYNC
ASYNC
Port pin with full synchronous and limited asynchronous interrupt function
Port pin with full synchronous and full asynchronous interrupt function
33.1.3 Analog functions
ACn
ACnOUT
ADCn
DACn
A_REF
Analog Comparator input pin n
Analog Comparator n Output
Analog to Digital Converter input pin n
Digital to Analog Converter output pin n
Analog Reference input pin
33.1.4 Timer/Counter and AWEX functions
OCnxLS
OCnxHS
Output Compare Channel x Low Side for Timer/Counter n
Output Compare Channel x High Side for Timer/Counter n
33.1.5 Communication functions
SCL
SDA
SCLIN
SCLOUT
SDAIN
SDAOUT
XCKn
Serial Clock for TWI
Serial Data for TWI
Serial Clock In for TWI when external driver interface is enabled
Serial Clock Out for TWI when external driver interface is enabled
Serial Data In for TWI when external driver interface is enabled
Serial Data Out for TWI when external driver interface is enabled
Transfer Clock for USART n
XMEGA A3BU [DATASHEET]
55
8362F–AVR–02/2013