The SAM G55 Xplained Pro headers EXT1, EXT3, and EXT4 offer access
to the I/O of the microcontroller in order to expand the board by connecting extensions to
the board. All these headers comply with the Xplained Pro standard extension header
specification. The headers have a pitch of 2.54mm.
Table 4-1. Extension Header
EXT1| Pin on EXT1 | SAM G55 pin | SAM G55 Peripheral Function | Shared Functionality |
|---|
| 1 [ID] | - | - | Communication line to ID chip on extension board. |
| 2 [GND] | - | - | GND |
| 3 [ADC(+)] | PA17 | AD0 | |
| 4 [ADC(-)] | PA18 | AD1 | |
| 5 [GPIO1] | PA26 | GPIO | UART0 RTS |
| 6 [GPIO2] | PA25 | GPIO | UART0 CTS |
| 7 [PWM(+)] | PA00 | TIOA0 | |
| 8 [PWM(-)] | PA23 | TIOA1 | |
| 9 [IRQ/GPIO] | PA24 | WKUP11 | |
| 10 [SPI_SS_B/GPIO] | PA29 | GPIO | |
| 11 [TWI_SDA] | PB10 | TWD4 | |
| 12 [TWI_SCL] | PB11 | TWCK4 | |
| 13 [USART_RX] | PA09 | USART RXD (URXD0) | |
| 14 [USART_TX] | PA10 | USART TXD (UTXD0) | |
| 15 [SPI_SS_A] | PA11 | SPI NPCS0 | |
| 16 [SPI_MOSI] | PA13 | SPI MOSI | EXT3 connector |
| 17 [SPI_MISO] | PA12 | SPI MISO | EXT3 connector |
| 18 [SPI_SCK] | PA14 | SPI SCK | EXT3 connector |
| 19 [GND] | - | - | GND |
| 20 [VCC] | - | - | VCC |
Table 4-2. Extension Header EXT3| Pin on EXT3 | SAM G55 pin | SAM G55 Shared Functionality | Shared Functionality |
|---|
| 1 [ID] | - | - | Communication line to ID chip on extension board. |
| 2 [GND] | - | - | GND |
| 3 [ADC(+)] | PA19 | AD2 | |
| 4 [ADC(-)] | PA20 | AD3 | |
| 5 [GPIO1] | PA30 | GPIO | |
| 6 [GPIO2] | PB15 | GPIO | |
| 7 [PWM(+)] | PA01 | TIOB0 | |
| 8 [PWM(-)] | PB13 | GPIO | |
| 9 [IRQ/GPIO] | PB03 | WKUP13 | |
| 10 [SPI_SS_B/GPIO] | PA15 | GPIO | |
| 11 [TWI_SDA] | PB08 | TWD4 | |
| 12 [TWI_SCL] | PB09 | TWCK4 | |
| 13 [USART_RX] | PB01 | USART6 RXD | EDBG (DGI USART) |
| 14 [USART_TX] | PB00 | USART0 TXD | EDBG (DGI USART) |
| 15 [SPI_SS_A] | PA05 | SPI NPCS1 | |
| 16 [SPI_MOSI] | PA13 | SPI MOSI | EXT1 connector (SPI MOSI) |
| 17 [SPI_MISO] | PA12 | SPI MISO | EXT1 connector (SPI MISO) |
| 18 [SPI_SCK] | PA14 | SPI SCK | EXT1 connector (SPI SCK) |
| 19 [GND] | - | - | GND |
| 20 [VCC] | - | - | VCC |
Table 4-3. Extension Header EXT4| Pin on EXT4 | SAM G55 pin | SAM G55 Peripheral Function | Shared Functionality |
|---|
| 1 [ID] | - | - | Communication line to ID chip on extension board. |
| 2 [GND] | - | - | GND |
| 3 [ADC(+)] | - | - | |
| 4 [ADC(-)] | - | - | |
| 5 [GPIO1] | PA31 | GPIO | PCK2 |
| 6 [GPIO2] | - | - | |
| 7 [PWM(+)] | - | - | |
| 8 [PWM(-)] | - | - | |
| 9 [IRQ/GPIO] | PB14 | - | |
| 10 [SPI_SS_B/GPIO] | - | - | |
| 11 [TWI_SDA] | PB10 | TWD4 | EDBG and EXT1 connector (TWI) |
| 12 [TWI_SCL] | PB11 | TWCK1 | EDBG and EXT1 connector (TWI) |
| 13 [USART_RX] | - | - | |
| 14 [USART_TX] | - | - | |
| 15 [SPI_SS_A] | - | - | |
| 16 [SPI_MOSI] | - | - | |
| 17 [SPI_MISO] | - | - | |
| 18 [SPI_SCK] | - | - | |
| 19 [GND] | - | - | GND |
| 20 [VCC] | - | - | VCC |
