12.1 Overview
Depending on the application, peripherals may require specific clock frequencies to operate correctly. The Generic Clock controller (GCLK) features 9 Generic Clock Generators 0..8 that can provide a wide range of clock frequencies.
Generators can be set to use different external and
internal oscillators as source. The clock of each Generator can be divided. The outputs
from the Generators are used as sources for the Peripheral Channels, which provide the
Generic Clocks (GCLK_PERIPH) to the peripheral modules, as shown in the 12.3
Block Diagram. The number of peripheral clocks depends on how many
peripherals the device has.
Note: The
Generic Clock Generator 0 is always the direct source of the GCLK_MAIN
signal.