After power-up, the device is set to its initial state and kept in reset, until the power has stabilized throughout the device. Once the power has stabilized, the device will use a 4MHz clock. This clock is derived from the 48MHz Internal Oscillator (OSC48M), which is configured to provide a 4MHz clock and used as a clock source for generic clock generator 0. Generic clock generator 0 is the main clock for the Power Manager (PM).
Some synchronous system clocks are active, allowing software execution.
Refer to the “Clock Mask Register” in the Power Manager for the list of default peripheral clocks running. Synchronous system clocks that are running are by default not divided and receive a 4MHz clock through generic clock generator 0. Other generic clocks are disabled.