4.2.2 Arduino Connectors

SAM C21 Xplained Pro implements Arduino shield connectors based on the Arduino Uno. All references to Arduino pin names are taken from the official Arduino schematics of the Arduino Uno.

CAUTION: The target section of SAM C21 Xplained Pro can be powered by 3.3V or 5.0V. The maximum voltage the I/O pins can tolerate depends on the supply voltage. Providing higher voltages like 5V to an I/O pin when the ATSAMC21J18A is powered by 3.3V could damage the board.
Info: Note that all pins do not have the exact same functionality as on the Arduino Uno on the shield connectors. Each shield should be checked for compatibility before it is connected.
Table 4-4. J802 - Power
Pin on J802SAM C21 pinArduino pin nameFunctionShared functionality
1-RFU--
2-IOREFVCC_TARGET_P3V3_P5V0-
3RESETNRESETTARGET_RESET-
4-3.3VVCC_P3V3-
5-5VVCC_P5V0-
6-GNDGND-
7-GNDGND-
8-VINVCC_EXT_P5V0-
Table 4-5. J803 - Analog
Pin on J803SAM C21 pinArduino pin nameFunctionShared functionality
1PB09ADC0INP1EXT1
2PB08ADC1INN1EXT1
3PA08ADC2AIN10EXT2
4PA09ADC3AIN11EXT2
5PB07ADC4AIN9 / INP2EXT3
6PB06ADC5AIN8 / INN2EXT3
Table 4-6. J804 - Digital Low
Pin on J804SAM C21 pinArduino pin nameFunctionShared functionality
1PA23D0 / RX0SERCOM3 PAD1 UART RXEXT1, EXT2, and EXT3
2PA22D1 / TX0SERCOM3 PAD0 UART TXEXT1, EXT2, and EXT3
3PA20D2GPIOEXT1
4PB12D3TC0_W0EXT1 and EDBG GPIO
5PA21D4GPIOEXT1
6PB13D5TC0_W1EXT1
7PB30D6TCC0_W0EXT2
8PB04D7GPIOEXT3
Table 4-7. J801 - Digital High
Pin on J801SAM C21 pinArduino pin nameFunctionShared functionality
1PB05D8GPIOEXT3
2PB31D9TCC0_W1EXT2
3PA27D10 / SPI-SSGPIOEXT3
4PB00D11 / SPI-MOSISERCOM5 PAD2EXT2, EXT3, EDBG SPI, and Shield
5PB02D12 / SPI-MISOSERCOM5 PAD0EXT2, EXT3, EDBG SPI, and Shield
6PB01D13 / SPI-SCKSERCOM5 PAD3EXT2, EXT3, EDBG SPI, and Shield
7-GND--
8PA03AREFADC / DAC VREFA
9PA12SDASERCOM2 PAD0EXT1, EXT2, EXT3, Crypto, and EDBG I2C
10PA13SCLSERCOM2 PAD1EXT1, EXT2, EXT3, Crypto, and EDBG I2C
Table 4-8. J800 - SPI
Pin on J800SAM C21 pinArduino pin nameFunctionShared functionality
1PB02MISOSERCOM5 PAD0EXT2, EXT3, EDBG SPI, and Shield
2-5VVCC_TARGET_P3V3_P5V0-
3PB01SCKSERCOM5 PAD3EXT2, EXT3, EDBG SPI, and Shield
4PB00MOSISERCOM5 PAD2EXT2, EXT3, EDBG SPI, and Shield
5RESETNRESETTARGET_RESET-
6-GNDGND-