How to detect the selected timer for "Timebase Source" during compile time ?

I don't think that's something that gets put into a #define anywhere.

I think the same. 2 ideas:

1. In FreeRTOS there are hooks which you can implement. If you set configUSE_TICK_HOOK to 1 and implement vApplicationTickHook, you can do your stuff at every timer tick.
2. Don't let STM32Cube generate that specific timebase source but init a periodic TIM of your own choice and add your own implementation of HAL_TIM_PeriodElapsedCallback HAL_InitTick HAL_SuspendTick and HAL_ResumeTick, easily copied from the generated stuff.

For this I define "user constants" in Cube projects. They become defines in main.h.

Like #define USE_HAL_TIMER 6

Then in C file:

#if USE_HAL_TIMER == 6

….

#elif USE_HAL_TIMER == 1

...

#endif

> Don't let STM32Cube generate that specific timebase source but init a periodic TIM of your own choice and add your own implementation of HAL_TIM_PeriodElapsedCallback

A good idea for optimization; HAL_TIM_PeriodElapsedCallback is quite heavy. But IMHO you can only hack the TIM interrupt handler in stm32....it.c and let Cube generate initialization and whatever it wants. Linker will discard unused functions.

-- pa

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