Within the SAM devices are a number of Generic Clocks; these are used to provide clocks to the various peripheral clock domains in the device in a standardized manner. One or more master source clocks can be selected as the input clock to a Generic Clock Generator, which can prescale down the input frequency to a slower rate for use in a peripheral.
Additionally, a number of individually selectable Generic Clock Channels are provided, which multiplex and gate the various generator outputs for one or more peripherals within the device. This setup allows for a single common generator to feed one or more channels, which can then be enabled or disabled individually as required.
Figure 1. Generic Clocks
