I setup a project for the STM32L431CBT6 MCU with the default main() from you. I can download and step through the program with the debugger. Then I added the HAL_Init() function with the corresponding #include “stm32l4xx_hal.h”. When I now step through the debugger, the HAL_Init() function jumps to the Infinite_Loop loop of the startup_stm32.s, when starting the systick timer in the HAL.
The SysTick_Handler() is available in stm32l4xx_it.c.
Could you help me, please? I have no idea why. The only thing I changed is the inlcude and the HAL_Init() in main.