32.5.1 I/O Lines

In order to use the SERCOM’s I/O lines, the I/O pins must be configured using the System Configuration registers only. I2C does not operate through PPS. See DEVCFG1 configuration bits SCOMn_HSEN in Configuration Bits Fuses and also CFGCON1 SCOMn_HSEN in CFGCON1(L) register. See CFGCON1(L) register from Related Links.

When the SERCOM is used in I²C mode, the SERCOM controls the direction and value of the I/O pins. In I²C mode pull-up resistors are disabled. External pull-up resistors are required for proper function.