Xplained Pro Standard Extension Headers

The Xplained Pro extension headers EXT1, EXT2, and EXT3 offer access to the I/O of the microcontroller to expand the board, for example, by connecting extensions to the board. These headers are based on the standard Xplained Pro extension header specification and the connections are shown in the table below. The headers have a pitch of 2.54 mm.

Table 1. Extension Header EXT1
EXT1 pin SAM E54 pin Function Shared functionality
1 [ID] - - Communication line to the ID chip on an extension board
2 [GND] - - Ground
3 [ADC(+)] PB04 ADC1/AIN[6] -
4 [ADC(-)] PB05 ADC1/AIN[7] -
5 [GPIO1] PA06 GPIO (RTS) -
6 [GPIO2] PA07 GPIO (CTS) -
7 [PWM(+)] PB08 TC4/WO[0] -
8 [PWM(-)] PB09 TC4/WO[1] -
9 [IRQ/GPIO] PB07 IRQ7/GPIO -
10 [SPI_SS_B/GPIO] PA27 GPIO -
11 [TWI_SDA] PA22 SERCOM3 PAD[0] I²C SDA PCC
12 [TWI_SCL] PA23 SERCOM3 PAD[1] I²C SCL PCC
13 [USART_RX] PA05 SERCOM0 PAD[1] UART RX -
14 [USART_TX] PA04 SERCOM0 PAD[0] UART TX -
15 [SPI_SS_A] PB28 SERCOM4 PAD[2] SPI SS -
16 [SPI_MOSI] PB27 SERCOM4 PAD[0] SPI MOSI -
17 [SPI_MISO] PB29 SERCOM4 PAD[3] SPI MISO -
18 [SPI_SCK] PB26 SERCOM4 PAD[1] SPI SCK -
19 [GND] - - Ground
20 [VCC] - - Power for extension board
Table 2. Extension Header EXT2
EXT2 pin SAM E54 pin Function Shared functionality
1 [ID] - - Communication line to the ID chip on an extension board
2 [GND] - - Ground
3 [ADC(+)] PB00 ADC0/AIN[12] -
4 [ADC(-)] PA03 ADC0/AIN[1] -
5 [GPIO1] PB01 GPIO -
6 [GPIO2] PB06 GPIO -
7 [PWM(+)] PB14 TCC4/WO[4] PCC
8 [PWM(-)] PB15 TCC4/WO[5] PCC
9 [IRQ/GPIO] PD00 IRQ0/GPIO -
10 [SPI_SS_B/GPIO] PB02 GPIO -
11 [TWI_SDA] PD08 SERCOM7 PAD[0] I²C SDA AT24MAC402, ATECC508, PCC, EXT3, and EDBG DGI
12 [TWI_SCL] PD09 SERCOM7 PAD[1] I²C SCL AT24MAC402, ATECC508, PCC, EXT3, and EDBG DGI
13 [USART_RX] PB17 SERCOM5 PAD[1] UART RX -
14 [USART_TX] PB16 SERCOM5 PAD[0] UART TX -
15 [SPI_SS_A] PC06 SERCOM6 PAD[2] SPI SS -
16 [SPI_MOSI] PC04 SERCOM6 PAD[0] SPI MOSI EXT3 and EDBG DGI
17 [SPI_MISO] PC07 SERCOM6 PAD[3] SPI MISO EXT3 and EDBG DGI
18 [SPI_SCK] PC05 SERCOM6 PAD[1] SPI SCK EXT3 and EDBG DGI
19 [GND] - - Ground
20 [VCC] - - Power for extension board
Table 3. Extension Header EXT3
EXT3 pin SAM E54 pin Function Shared functionality
1 [ID] - - Communication line to the ID chip on an extension board
2 [GND] - - Ground
3 [ADC(+)] PC02 ADC1/AIN[4]  
4 [ADC(-)] PC03 ADC1/AIN[5]  
5 [GPIO1] PC01 GPIO  
6 [GPIO2] PC10 GPIO -
7 [PWM(+)] PD10 TCC0/WO[3] -
8 [PWM(-)] PD11 TCC0/WO[4] -
9 [IRQ/GPIO] PC30 IRQ14/GPIO -
10 [SPI_SS_B/GPIO] PC31 GPIO -
11 [TWI_SDA] PD08 SERCOM7 PAD[0] I²C SDA AT24MAC402, ATECC508, PCC, EXT2, and EDBG DGI
12 [TWI_SCL] PD09 SERCOM7 PAD[1] I²C SCL AT24MAC402, ATECC508, PCC, EXT2, and EDBG DGI
13 [USART_RX] PC23 SERCOM1 PAD[1] UART RX -
14 [USART_TX] PC22 SERCOM1 PAD[0] UART TX -
15 [SPI_SS_A] PC14 GPIO -
16 [SPI_MOSI] PC04 SERCOM6 PAD[0] SPI MOSI EXT2 and EDBG DGI
17 [SPI_MISO] PC07 SERCOM6 PAD[3] SPI MISO EXT2 and EDBG DGI
18 [SPI_SCK] PC05 SERCOM6 PAD[1] SPI SCK EXT2 and EDBG DGI
19 [GND] - - Ground
20 [VCC] - - Power for extension board