The Power Management Controller (PMC) optimizes power consumption by controlling all system and user peripheral clocks. The PMC enables/disables the clock inputs to many of the peripherals and the Cortex-M7 processor.
The Supply Controller selects either the Slow RC oscillator or the 32.768 kHz crystal oscillator as the source of SLCK. The unused oscillator is disabled automatically so that power consumption is optimized.
By default, at startup, the chip runs out of MCK using the Main RC oscillator running at 12 MHz.