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Gregory Nutt f073092fad The STM32F4Discovery board doesn't come with a Low speed external oscillator so the default LSE source for the RTC doesn't work. ... In stm32_rtcc.c the up_rtcinitialize() logic doesn't work with the LSI. The check on RTC_MAGIC on the BK0R register lead to rtc_setup() call that rightfully enables the lsi clock; but the next times, when the rtc is already setup, the rtc_resume() call does NOT start the lsi clock! The right place to put LSE/LSI initialisation is inside stm32_stdclockconfig() in stm32fxxxxx_rcc.c. Doing this I checked the possible uses of the LSI and the LSE sources: the LSI can be used for RTC and/or the IWDG, while the LSE only for the RTC (and to output the MCO1 pin).. This change is not verifed for any other platforms. From Leo Aloe3132		2015-03-29 15:34:48 -06:00
arch	The STM32F4Discovery board doesn't come with a Low speed external oscillator so the default LSE source for the RTC doesn't work.	2015-03-29 15:34:48 -06:00