17.2 IDLE mode
Power control register is set to ‘01h’ to enter into IDLE mode. In IDLE mode, internal oscillation
circuits remain active. Oscillation continues and peripherals are operated normally, but CPU stops.
It is released by reset or an interrupt. To be released by an interrupt, the interrupt should be enabled
before IDLE mode. If using a reset, because the device is initialized, registers become to have reset
values.