目的
節電化


# include "mbed.h"

void s_clk4();

DigitalOut myled(PA_4); RawSerial pc(PA_2, PA_3); //010 tx, rx 

int main()
{

    //__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);//4Mhz 1.8
    __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE2);//4Mhz 1.5 560uA
    //__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE3);//4Mhz 1.2 460uA W_Not_Flash

    s_clk4();
    pc.baud(9600); //16mz
    //printf("%d Hz\r\n", SystemCoreClock);

    while(1) {
        myled = 1;
        wait(0.2);
        myled = 0;
        wait(0.2);

        printf("%d Hz\r\n", SystemCoreClock);

    }//while

}//main


void s_clk4()
{
  /*4mz*/

  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
  HAL_RCC_OscConfig(&RCC_OscInitStruct);

  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
                              |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV4;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
  HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0);

 }//s_clk4