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STM32F103????????????

STM32F103??????STC?????????????ARM Cortex-M3??????????????????AHB????????????????????????????????I2C?SPI?UART?ADC?DAC?????????????????????

????????????STM32F103???????????????PLL???????????????????

1. HSI?PLL??

STM32F103?????????HSI????????PLL??????HSI????????????32.768 kHz?PLL???HSI?????????????????PLL_MUL?????????

• HSI????HSE??HSE???HSI?????????????HSE_PREDIV_DIV1???HSI??32.768 kHz??1????32.768 kHz?
• PLL????PLL_MUL????PLL_MUL???????????????PLL_MUL???16??????PLLCLK = (HSI / 2) * PLL_MUL = (32.768 kHz / 2) * 16 = 64 MHz?

2. ???????

?STM32F103??PLL?????????????????

3. PCB?HSI??

???PCB???????????

• HSI??????????????????????
• PCB??????????HSI???HSE????PLL??????
• ???????????????????????????

4. ????????

?STM32F103??????????????????

void SystemClock_Config(void){    RCC_ClkInitTypeDef clkinitstruct = {0};    RCC_OscInitTypeDef oscinitstruct = {0};    /* ??PLL */    oscinitstruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;    oscinitstruct.HSEState = RCC_HSE_OFF;    oscinitstruct.HSIState = RCC_HSI_ON;    oscinitstruct.PLL.PLLState = RCC_PLL_ON;    oscinitstruct.PLL.PLLSource = RCC_PLLSOURCE_HSI_DIV2;    oscinitstruct.PLL.PLLMUL = RCC_PLL_MUL16;    if (HAL_RCC_OscConfig(&oscinitstruct) != HAL_OK)    {        /* ????? */        while(1);    }    /* ?????? */    clkinitstruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);    clkinitstruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;    clkinitstruct.AHBCLKDivider = RCC_SYSCLK_DIV1;    clkinitstruct.APB2CLKDivider = RCC_HCLK_DIV1;    clkinitstruct.APB1CLKDivider = RCC_HCLK_DIV2;    if (HAL_RCC_ClockConfig(&clkinitstruct, FLASH_LATENCY_2) != HAL_OK)    {        /* ????? */        while(1);    }}

5. ????

???????STM32F103???????????????????PLL?????????????????????????????????????????????????????????????

??????????

• ???????????PLL?????
• ?????????????????
• ????????????????????????