SWCU191 February 2022 CC1311P3 , CC1311R3 , CC2651P3 , CC2651R3 , CC2651R3SIPA
The System CPU can program the operational mode for peripherals that use the SCE clock rate, so that these are active when the System CPU is inactive. Through CPU programming, the AUX domain can be set to active, low-power, or power-down modes with the register and bit settings shown in Figure 20-2.
Given the AUX Domain has its own interface to the Power Controller, it can remain active even if the System CPU is in standby. This can be useful to generate clock to timers or enable COMPA or COMPB wakeup, for example.
Each operational mode is characterized by:
SCE clock rate
The system does not change the AUX operational mode request. As shown in Figure 20-2, the system overrides the request as long as the AUX wake-up event is active.
Table 20-1 summarizes the properties for each operational mode.
Operational Mode | Active | Low-Power | Power-Down | |||
---|---|---|---|---|---|---|
AUX SCE Clock Source | AON_PMCTL:AUXSCECLK.SRC | SCLK_MF | AON_PMCTL:AUXSCECLK.PDSRC | |||
SCE Clock Rate | 24 MHz | 2 MHz | 2 MHz | 32.768 kHz | NO_CLOCK | |
AUX Bus Clock Rate | MCU Inactive | 24 MHz | 24 MHz | 2 MHz | 32.768 kHz | NO_CLOCK |
MCU Active | 24 MHz | 24 MHz | 24 MHz | 24 MHz | 24 MHz | |
Power Supply Request | DCDC or GLDO | µLDO | µLDO |
Follow the steps described in AUX_SYSIF:OPMODEREQ to request an operational mode. For AUX wakeup, see Section 20.1.
An Active operational mode request prevents the system from entering standby or shutdown because the power controller requests a high-frequency clock source.