4.1.1 Xplained Pro Standard Extension Header
The SAM D11 Xplained Pro header EXT1 offers access to the I/O of the microcontroller in order to expand the board e.g. by connecting extensions to the board. This header is based on the standard extension header specified in Table 3-4. The header has a pitch of 2.54mm.
| Pin on EXT1 | SAM D11 pin | Function | Shared functionality |
|---|---|---|---|
| 1 [ID] | - | - | Communication line to ID chip on extension board. |
| 2 [GND] | - | - | GND |
| 3 [ADC(+)] | PA02 | AIN[0] | QTouch Button 1 |
| 4 [ADC(-)] | PA03 | AIN[1] | QTouch Button 2 |
| 5 [GPIO1] | PA04 | GPIO | |
| 6 [GPIO2] | PA05 | GPIO | |
| 7 [PWM(+)] | PA16 | TC1/WO[0] | LED0 and EDBG GPIO |
| 8 [PWM(-)] | PA17 | TC1/WO[1] | EDBG GPIO |
| 9 [IRQ/GPIO] | PA14 | NMI | SW0 and EDBG GPIO |
| 10 [SPI_SS_B/GPIO] | PA15 | GPIO | EDBG GPIO |
| 11 [TWI_SDA] | PA22 | SERCOM1 PAD[0] I²C SDA | EDBG I²C |
| 12 [TWI_SCL] | PA23 | SERCOM1 PAD[1] I²C SCL | EDBG I²C |
| 13 [USART_RX] | PA11 | SERCOM2 PAD[3] UART RX | EDBG CDC |
| 14 [USART_TX] | PA10 | SERCOM2 PAD[2] UART TX | EDBG CDC |
| 15 [SPI_SS_A] | PA08 | SERCOM0 PAD[2] SPI SS | 32kHz Crystal footprint |
| 16 [SPI_MOSI] | PA06 | SERCOM0 PAD[0] SPI MOSI | EDBG SPI |
| 17 [SPI_MISO] | PA09 | SERCOM0 PAD[3] SPI MISO | 32kHz Crystal footprint and EDBG SPI |
| 18 [SPI_SCK] | PA07 | SERCOM0 PAD[1] SPI SCK | EDBG SPI |
| 19 [GND] | - | - | GND |
| 20 [VCC] | - | - | VCC |
