31.4 Signal Description
See the respective SERCOM mode chapters for details.
CAUTION: I/Os for SERCOM peripherals are grouped into IO sets.
For these peripherals, it is mandatory to use I/Os that belong to the same I/O set. The timings are not guaranteed when I/Os from different I/O sets are mixed. Refer to the Pinout and Packaging chapter to get IOSET definitions.