Bug report: PLL configuration in HAL_RCC_OscConfig() returns HAL_ERROR, if HSE is configured and PLL is the system clock source

[TS1]

Working with the STM32F429 Discovery board and STMCube_FW_F4_V1.21.0 I've got the same problem several times.

If I use the main.c provided with the application examples, the code will run into an endless loop after calling HAL_RCC_OscConfig and taking care of the return value.

The program works as expected, if the return value is ignored.

The configuration of the PLL causes this behaviour:

The check, if the PLL is used as system clock source will go to the else path and returns HAL_ERROR. The calling function expects HAL_OK.

[Khouloud GARSI]

Hi @Torsten Schönitz​ ,

I'm not able to reproduce your issue. The "HAL_ERROR" should not be called if everything is configured correctly (I'm supposing your board is ok).

For further debug, you may share a project that is not working for you, I will check it using our HW.

Khouloud.

[TS1]

Hi Khouloud,

I'm new to this community and just don't know, how to share the whole project.

But perhaps you can tell me, what should happen, when the function HAL_RCC_OscConfig () comes to the configuration of the PLL:

  /*-------------------------------- PLL Configuration -----------------------*/
  /* Check the parameters */
  assert_param(IS_RCC_PLL(RCC_OscInitStruct->PLL.PLLState));
  if ((RCC_OscInitStruct->PLL.PLLState) != RCC_PLL_NONE)
  {
    /* Check if the PLL is used as system clock or not */
    if(__HAL_RCC_GET_SYSCLK_SOURCE() != RCC_CFGR_SWS_PLL)
    {
      if((RCC_OscInitStruct->PLL.PLLState) == RCC_PLL_ON)
      {
        /* Check the parameters */
        assert_param(IS_RCC_PLLSOURCE(RCC_OscInitStruct->PLL.PLLSource));
        assert_param(IS_RCC_PLLM_VALUE(RCC_OscInitStruct->PLL.PLLM));
        assert_param(IS_RCC_PLLN_VALUE(RCC_OscInitStruct->PLL.PLLN));
        assert_param(IS_RCC_PLLP_VALUE(RCC_OscInitStruct->PLL.PLLP));
        assert_param(IS_RCC_PLLQ_VALUE(RCC_OscInitStruct->PLL.PLLQ));

In my projects the if-statement (if PLL is used as system clock) is false, because the system clock source is equal to RCC_CFGR_SWS_PLL. So the else path will be selected, that is returning HAL_ERROR.

The projects are working as expected, if I ignore the return value in the calling function.

Torsten