1.1 UART I²C and Boot Pin Configurations

Table 1-1. Port Pin and SERCOM Instance for UART and I²C
Protocol	Port Pin Configuration	SERCOM Instance
UART	PA18 - TX - SERCOM1/PAD2 PA19 - RX - SERCOM1/PAD3	SERCOM 1
I²C	PA22 - SDA - SERCOM3/PAD0 - External Pull-up required PA23 - SCL - SERCOM3/PAD1 - External Pull-up required	SERCOM 3
Boot pin	PA27 - GPIO - Input - Pull-up enabled	-

Table 1-2. UART and I²C Communication Configurations
Protocol	Communication Parameters
UART	115200 baud, 8-bit, Even parity, 1 Stop bit.
I²C	Up to 400 kHz speed. I²C client 7-bit address (0x40) - 1000-000x (where x = 0 for write, 1 for read). Address is fixed and not programmable through any hardware setting.

1.1 UART I2C and Boot Pin Configurations