3.1 I/O Multiplexing

VQFN48/

TQFP48

VQFN32/

TQFP32

SPDIP28/

SOIC28/

SSOP28
Pin name (1,2)SpecialADC0PTCACnDAC0ZCDnUSARTnSPInTWIn(4)TCA0TCA1TCBnTCDnEVSYSCCL-LUTn
443022PA0EXTCLKXO/Y00,TxDWO00,IN0
453123PA1X1/Y10,RxDWO10,IN1
463224PA2TWIX2/Y20,XCK0,SDA(H)WO20,WOEVOUTA0,IN2
47125PA3TWIX3/Y30,XDIR0,SCL(H)WO31,WO0,OUT
48226PA4X4/Y40,TxD(3)0,MOSIWO40,WOA
1327PA5X5/Y50,RxD(3)0,MISOWO50,WOB
2428PA6X6/Y60,XCK(3)0,SCK0,WOC0,OUT(3)
351PA7CLKOUTX7/Y7

0,OUT

1,OUT

2,OUT

0,OUT

1,OUT

0,XDIR(3)0,SS0,WODEVOUTA (3)
4PB0X8/Y83,TxDWO0(3)WO04,IN0
5PB1X9/Y93,RxD WO1(3)WO14,IN1
6PB2X10/Y103,XCK1,SDA(H)(3)WO2(3)WO2EVOUTB4,IN2
7PB3X11/Y113,XDIR1,SCL(H)(3)WO3(3)WO34,OUT
8PB4X12/Y123,TxD(3)1,MOSI(3)WO4(3)WO42,WO(3)0,WOA(3)
9PB5X13/Y133,RxD(3)1,MISO(3)WO5(3)WO53,WO0,WOB(3)
1062PC01,TxD1,MOSIWO0(3)2,WO1,IN0
1173PC11,RxD1,MISOWO1(3)3,WO(3)1,IN1
1284PC2TWI1,XCK1,SCK0,SDA(H)(3)WO2(3)EVOUTC1,IN2
1395PC3TWI1,XDIR1,SS0,SCL(H)(3)WO3(3)1,OUT
14VDD
15GND
16PC41,TxD(3)1,MOSI(3)WO4(3)WO0(3)
17PC51,RxD(3)1,MISO(3)WO5(3)WO1(3)
18PC6

0,OUT(3)

1,OUT(3)

2,OUT(3)

1,XCK(3)1,SCK(3)0,SDA(C)WO2(3)4,WO(3)1,OUT(3)
19PC7

0,OUT(3)

1,OUT(3)

1,XDIR(3)1,SS(3)0,SCL(C)EVOUTC (3)
20106PD0AIN0X16/Y16

0,AINN1

1,AINN1

2,AINN1

WO0(3)2,IN0
21117PD1AIN1X17/Y170,ZCINWO1(3)2,IN1
22128PD2AIN2X18/Y18

0,AINP0

1,AINP0

2,AINP0

WO2(3)EVOUTD2,IN2
23139PD3AIN3X19/Y19

0,AINN0

1,AINP1

WO3(3)2,OUT
241410PD4AIN4X20/Y20

1,AINP2

2,AINP1

WO4(3)
251511PD5AIN5X21/Y211,AINN0WO5(3)
261612PD6AIN6X22/Y22

0,AINP3

1,AINP3

2,AINP3

VOUT2,OUT(3)
271713PD7VREFAAIN7X23/Y23

0,AINN2

1,AINN2

2,AINN0/AINN2

EVOUTD (3)
281814AVDD
291915GND
30PE0AIN8X24/Y240,AINP14,TxD0,MOSI(3)WO0(3)
31PE1AIN9X25/Y252,AINP24,RxD0,MISO(3)WO1(3)
32PE2AIN10X26/Y260,AINP24,XCK0,SCK(3)WO2(3)EVOUTE
33PE3AIN11X27/Y271,ZCIN4,XDIR0,SS(3)WO3(3)
342016PF0XTAL32K1AIN16(6)X32/Y322,TxDWO0(3)0,WOA(3)3,IN0
352117PF1XTAL32K2AIN17(6)X33/Y332,RxDWO1(3)0,WOB(3)3,IN1
3622PF2TWIAIN18(6)X34/Y342,XCK1,SDA(H)WO2 (3)0,WOC (3)EVOUTF 3,IN2
3723PF3TWIAIN19(6)X35/Y352, XDIR1,SCL(H)WO3 (3)0,WOD (3)3,OUT
3824PF4AIN20(6)X36/Y362, TxD (3)WO4 (3)0,WO (3)
3925PF5AIN21(6)X37Y372, RxD (3)WO5(3)1,WO(3)
402618PF6 (5)RESET
412719UPDI
422820VDD
432921GND
Note:
  1. Pin names are of type Pxn, with x being the PORT instance (A, B, C, ...) and n the pin number. Notation for signals is PORTx_PINn. All pins can be used as event input.
  2. All pins can be used for external interrupt, where pins Px2 and Px6 of each port have full asynchronous detection.
  3. Alternate pin positions. For selecting the alternate positions, refer to the Port Multiplexer section.
  4. The TWI pins that can be used as host or client are marked H. Pins with client only are marked C.
  5. Input-only.
  6. Positive input-only.