15.1 Overview
Depending on the application, peripherals may require specific clock frequencies to operate correctly. The Generic Clock controller GCLK provides nine Generic Clock Generators 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 Generic Clock Multiplexers, which provide the Generic Clock
(GCLK_PERIPHERAL) to the peripheral modules, as shown in Generic Clock Controller Block
Diagram. The number of Peripheral Clocks depends on how many peripherals the device has.
Note: The Generator 0 is always the
direct source of the GCLK_MAIN signal.