6.

I/O Multiplexing

Each pin is by default controlled by the PORT as a general purpose I/O and alternatively it can be

assigned to one of the peripheral functions.

The following table describes the peripheral signals multiplexed to the PORT I/O pins.

Table 6-1. PORT Function Multiplexing

No

PAD

EXTINT

PCINT

ADC/AC

OSC

T/C # 0

T/C # 1

USART

I2C

SPI

1

PD[3]

INT1

PCINT19

OC2B

2

PD[4]

PCINT20

T0

XCK0

3

PE[0]

PCINT24

ACO

ICP4

SDA1

4

VCC

5

GND

6

PE[1]

PCINT25

TC4

SCL1

7

PB[6]

PCINT6

XTAL1/TOSC1

8

PB[7]

PCINT7

XTAL2/TOSC2

9

PD[5]

PCINT21

OC0B

T1

10

PD[6]

PCINT22

AIN0

OC0A

11

PD[7]

PCINT23

AIN1

12

PB[0]

PCINT0

CLKO

ICP1

13

PB[1]

PCINT1

OC1A

14

PB[2]

PCINT2

OC1B

SS0

15

PB[3]

PCINT3

OC2A

TXD1

MOSI0

16

PB[4]

PCINT4

RXD1

MISO0

17

PB[5]

PCINT5

XCK0

SCK0

18

AVCC

19

PE[2]

PCINT26

ADC6

ICP3

SS1

20

AREF

21

GND

22

PE[3]

PCINT27

ADC7

T3

MOSI1

23

PC[0]

PCINT8

ADC0

MISO1

24

PC[1]

PCINT9

ADC1

SCK1

25

PC[2]

PCINT10

ADC2

26

PC[3]

PCINT11

ADC3

27

PC[4]

PCINT12

ADC4

SDA0

28

PC[5]

PCINT13

ADC5

SCL0

29

PC[6]/RESET

PCINT14

30

PD[0]

PCINT16

OC3A

RXD0

31

PD[1]

PCINT17

OC4A

TXD0

32

PD[2]

INT0

PCINT18

OC3B

OC4B

Atmel ATmega48PB/88PB/168PB [DATASHEET]

Atmel-42176G-ATmega48PB/88PB/168PB_Datasheet_Summary-03/2016

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