Hi all,
STM32 start executes the following during startup in main.c:
HAL_Init();
SystemClock_Config();
Initialize all configured peripherals (e.g., MX_GPIO_Init())
Enter the main while loop
However, I've observed a cold-start issue:
If the power supply is disconnected for 3–5 seconds or more, the system hangs and never reaches the main while loop after reboot.
If the supply is disconnected for a short interval or a manual reset is applied, the system boots normally.
While debugging, I suspected that the LSE/LSI/HSI oscillators might need more time to stabilize.
Looking into HAL_RCC_OscConfig(), it waits for the HSI to be ready by checking RCC_FLAG_HSIRDY with a timeout mechanism:
/* Get Start Tick */
tickstart = HAL_GetTick();
/* Wait till HSI is ready */
while(__HAL_RCC_GET_FLAG(RCC_FLAG_HSIRDY) == 0U)
{
if((HAL_GetTick() - tickstart ) > HSI_TIMEOUT_VALUE)
{
return HAL_TIMEOUT;
}
}
When I set a breakpoint here, I noticed:
It seems the HAL tick is not advancing at this point, causing the function to hang indefinitely.
Has anyone encountered a similar issue, or can explain why HAL_GetTick() would not increment during system clock configuration at cold start? Any suggestions on how to fix this would be greatly appreciated.
