Processor Expert provides possibility to switch between processor modes by providing concept of “operation modes”.
The CPU component provides a function SetOperationMode that can be called to select one the following general modes:
- RUN – normal mode, running at full speed.
- WAIT – core sleeps, but the peripherals are running
- SLEEP – both core and peripherals sleep and can wake up to continue execution
- STOP – both core and peripherals sleep and usually can wake up only via reset
These modes are mapped to the platform specific modes of the chip. By switching to WAIT/SLEEP/STOP modes when possible (for example no computation is done for a while), it's possible to achieve a lower consumption of the whole chip.
The following table shows an example of the operation modes mapping for Kinetis L that shows the state of the core, bus and recovery method for each mode:
The Very low power mode option is available in Clock configurations of CPU properties (see below), i.e. the selection of the power mode is done by combination of the SetOperationMode and SetClockConfiguration methods.
The exact mapping of the DOM_xxx options can be configured in the CPU component inspector (the Advenced view has be enabled). For example the DOM_SLEEP can be mapped to normal stop mode, very low power stop, partial stop 1 or partial stop 2 of Kinetis L.
I don't see a Very Low Power item under configuration on my chip.
