LSI as RTC clock source on certain STM targets #11508
Description
Description
Currently it is possible through a switch in mbed_app.json (specific to the FAMILY_STM32 of devices) to control whether to use LSE or LSI as clock source for the RTC.
Today however I realized that configuring "lse_available" : 0 in the overrides section of the STM32H743ZI will cause the build to fail in mbed_overrides.c at line 63 with the definition of RCC_RTCCLKSOURCE_NO_CLK seemingly missing. Inspecting the codes of other STM32XY boards revealed that this is defined in stm32xy_hal_rcc.h, but this is seemingly missing for the H7.
Thus, my first question is:
May I go ahead and simply create a merge request adding the required line directly into this HAL file or does the H7 deploy another mechanism/symbol for that?
On a sidenote I also found out that the definition of RCC_RTCCLKSOURCE_NO_CLK is absent in the HAL files of the STM32L4 and STM32WB family of devices as well.
For the STM32L4 family this is solved in the respective stm32_hal_legacy.h, in line 2805 where it says:
#if defined(STM32L4)
#define RCC_RTCCLKSOURCE_NO_CLK RCC_RTCCLKSOURCE_NONE
whereas the STM32WB family of devices doesn not have a section like this.
So I went ahead and started a compilation after adapting targets.json to NOT use the LSE for a STM32WB target which resulted in a compilation error in file mbed_overrides.c with the same error as for the H7: No definition of RCC_RTCCLKSOURCE_NO_CLK present.
Which leads me to my second question:
In the same or another merge request, should I expand the line 2805 (#if defined(STM32L4)) to something like #if defined(STM32L4) || defined(STM32WB)?
Because as far as I could determine the stm32wbxx_hal_rcc.h does contain a definition of RCC_RTCCLKSOURCE_NONE, but RCC_RTCCLKSOURCE_NO_CLK is required by mbed_overrides.c.
Or am I missing something here?
Further information
- Related Targets: STM32H7, STM32L4, STM32WB
- Toolchain I tested with: GCC_ARM, Version 6. Release Q2 2017
- Tools I used: mbed-cli, Version 0.22.0
Issue request type
[x] Question
[ ] Enhancement
[ ] Bug