Overriding the default SystemClock_Config function?

[Bambo]

Hi, i'm trying to override the WEAK SystemClock_Config defined in the variant but my debugger doesn't detect that the new function is being called.

Is this the correct way to override?

file named "Sysclock_Config.h" contents:

Code: Select all

extern "C" void SystemClock_Config(void) {
    RCC_OscInitTypeDef RCC_OscInitStruct = {};
    RCC_ClkInitTypeDef RCC_ClkInitStruct = {};

    /* Configure LSE Drive Capability */
    HAL_PWR_EnableBkUpAccess();
    __HAL_RCC_LSEDRIVE_CONFIG(RCC_LSEDRIVE_LOW);
    /* Initializes the CPU, AHB and APB busses clocks */
    RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSE | RCC_OSCILLATORTYPE_MSI;
    RCC_OscInitStruct.LSEState = RCC_LSE_ON;
    RCC_OscInitStruct.MSIState = RCC_MSI_ON;
    RCC_OscInitStruct.MSICalibrationValue = 0;
    RCC_OscInitStruct.MSIClockRange = RCC_MSIRANGE_6;
    RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
    RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_MSI;
    RCC_OscInitStruct.PLL.PLLM = 1;
    RCC_OscInitStruct.PLL.PLLN = 40;
    RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV7;
    RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;
    RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;
    if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK) {
        Error_Handler();
    }
    /* Initializes the CPU, AHB and APB busses clocks */
    RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_SYSCLK
        | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2;
    RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
    RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
    RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
    RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

    if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_4) != HAL_OK) {
        Error_Handler();
    }
    /* Configure the main internal regulator output voltage */
    if (HAL_PWREx_ControlVoltageScaling(PWR_REGULATOR_VOLTAGE_SCALE1) != HAL_OK) {
        Error_Handler();
    }
    /* Enable MSI Auto calibration */
    HAL_RCCEx_EnableMSIPLLMode();
}

And then in Test.ino:

Code: Select all

#include "Sysclock_Config.h"

void setup() {
}

void loop() {
}

[stevestrong]

If you don't use the function it will not be called, and not even linked.
Try to call the function in setup.

[fpiSTM]

Yes this is the correct way.

Code: Select all

extern "C" void SystemClock_Config(void) {
...
}

it seems strange to define a c function in .h file.
In general the simplest way is to define it before the setup() function.

Steve, this is a weak function by default called during the init of the variant.