Resolved! TIM3 periodElapsedCallback never called
In my code, after setting an on-board LED, the timer is started like this. __HAL_TIM_SET_COUNTER(&htim3, 0); while(HAL_TIM_Base_Start_IT(&htim3) != HAL_BUSY);In debugging mode, I saw that the CNT register was in fact incrementing, however in would al...