Resolved! Missing EXTI IR handler code
I'm using the EXTI1 interrupt and defined the EXTI1 handler like this:void EXTI1_IRQHandler(void) { __HAL_GPIO_EXTI_CLEAR_IT(GPIO_PIN_1); if (GPIOA->IDR & 0x0100 { EXTI->PR = 1; (void) EXTI->PR; NVIC_ClearPendingIRQ(EXTI0_IRQn); ...