* stm32wl(rak3172): implement cpuDeepSleep()/shutdown() via STM32LowPower
cpuDeepSleep() was an empty stub, so the SDS deep-sleep PowerFSM state
and low-battery shutdown did nothing but leave the CPU running at full
power. Power::shutdown() also didn't include STM32WL in its arch list,
so an explicit shutdown command just logged a FIXME warning.
Adds STM32LowPower as a lib_dep (rak3172 only, mirroring STM32RTC) and
implements cpuDeepSleep() using it. Standby mode is used for both the
finite-wake (SDS/low battery) and forever (shutdown) paths, via
LowPower.shutdown(), with or without an RTC alarm.
If the LSE-backed hardware RTC never came up (stm32wlRtcAvailable()
false), this is a no-op - safer than sleeping without a confirmed wake
source. LowPower.shutdown() resets the MCU on wake and should never
return; if it somehow does, force a reset via HAL_NVIC_SystemReset()
rather than hanging the device silently forever.
Gated behind the existing HAS_LSE flag, so this is inert on every
variant but rak3172.
Assisted-by: Claude Sonnet 5 <noreply@anthropic.com>
Signed-off-by: Andrew Yong <me@ndoo.sg>
* feat(stm32wl): Warn and reset when trying to deepSleep without RTC
This is to prevent leaving the firmware catanonic when firmware has run
its shutdown routine but doesn't actually shutdown.
Signed-off-by: Andrew Yong <me@ndoo.sg>
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Signed-off-by: Andrew Yong <me@ndoo.sg>
Andrew YongandGitHub
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