stm32内部高速晶振打开作为主时钟

首先建议你别这么干，因为内部晶振特别容易受温度等外界影响，很容易卡死或堵死程序

我是因为没画外部晶振电路，所以只能开内部晶振来作为时钟

适用于stm32f103系列

把下面的代码换掉源文件里的时钟源配置

/* 开启HSI 即内部晶振时钟 */RCC->CR |= (uint32_t)0x00000001; 
//  RCC_DeInit();
//  RCC_HSEConfig(RCC_HSE_ON);  //使能内部时钟 HSI/*选择HSI为PLL的时钟源HSI必须2分频给PLL*/RCC->CFGR |= (uint32_t)RCC_CFGR_PLLSRC_HSI_Div2; /*PLLCLK=8/2*9=36MHz   设置倍频得到时钟源PLL的频率*/RCC->CFGR |= (uint32_t)RCC_CFGR_PLLMULL9;/* PLL不分频输出  */RCC->CFGR |= (uint32_t)RCC_CFGR_HPRE_DIV1;/* 使能 PLL时钟 */RCC->CR |= RCC_CR_PLLON;/* 等待PLL时钟就绪*/while((RCC->CR & RCC_CR_PLLRDY) == 0){}/* 选择PLL为系统时钟的时钟源 */RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_SW));RCC->CFGR |= (uint32_t)RCC_CFGR_SW_PLL;    /* 等到PLL成为系统时钟的时钟源*/while ((RCC->CFGR & (uint32_t)RCC_CFGR_SWS) != (uint32_t)0x08){}	

我的时钟配置文件

system_stm32f10x.c

/********************************************************************************* @file    system_stm32f10x.c* @author  MCD Application Team* @version V3.5.0* @date    11-March-2011* @brief   CMSIS Cortex-M3 Device Peripheral Access Layer System Source File.* * 1.  This file provides two functions and one global variable to be called from *     user application:*      - SystemInit(): Setups the system clock (System clock source, PLL Multiplier*                      factors, AHB/APBx prescalers and Flash settings). *                      This function is called at startup just after reset and *                      before branch to main program. This call is made inside*                      the "startup_stm32f10x_xx.s" file.**      - SystemCoreClock variable: Contains the core clock (HCLK), it can be used*                                  by the user application to setup the SysTick *                                  timer or configure other parameters.*                                     *      - SystemCoreClockUpdate(): Updates the variable SystemCoreClock and must*                                 be called whenever the core clock is changed*                                 during program execution.** 2. After each device reset the HSI (8 MHz) is used as system clock source.*    Then SystemInit() function is called, in "startup_stm32f10x_xx.s" file, to*    configure the system clock before to branch to main program.** 3. If the system clock source selected by user fails to startup, the SystemInit()*    function will do nothing and HSI still used as system clock source. User can *    add some code to deal with this issue inside the SetSysClock() function.** 4. The default value of HSE crystal is set to 8 MHz (or 25 MHz, depedning on*    the product used), refer to "HSE_VALUE" define in "stm32f10x.h" file. *    When HSE is used as system clock source, directly or through PLL, and you*    are using different crystal you have to adapt the HSE value to your own*    configuration.*        ******************************************************************************* @attention** THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS* WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE* TIME. AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY* DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING* FROM THE CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE* CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.** <h2><center>&copy; COPYRIGHT 2011 STMicroelectronics</center></h2>*******************************************************************************//** @addtogroup CMSIS* @{*//** @addtogroup stm32f10x_system* @{*/  /** @addtogroup STM32F10x_System_Private_Includes* @{*/#include "stm32f10x.h"/*** @}*//** @addtogroup STM32F10x_System_Private_TypesDefinitions* @{*//*** @}*//** @addtogroup STM32F10x_System_Private_Defines* @{*//*!< Uncomment the line corresponding to the desired System clock (SYSCLK)frequency (after reset the HSI is used as SYSCLK source)IMPORTANT NOTE:============== 1. After each device reset the HSI is used as System clock source.2. Please make sure that the selected System clock doesn't exceed your device'smaximum frequency.3. If none of the define below is enabled, the HSI is used as System clocksource.4. The System clock configuration functions provided within this file assume that:- For Low, Medium and High density Value line devices an external 8MHz crystal is used to drive the System clock.- For Low, Medium and High density devices an external 8MHz crystal isused to drive the System clock.- For Connectivity line devices an external 25MHz crystal is used to drivethe System clock.If you are using different crystal you have to adapt those functions accordingly.*/#if defined (STM32F10X_LD_VL) || (defined STM32F10X_MD_VL) || (defined STM32F10X_HD_VL)
/* #define SYSCLK_FREQ_HSE    HSE_VALUE */#define SYSCLK_FREQ_24MHz  24000000
#else
/* #define SYSCLK_FREQ_HSE    HSE_VALUE */
/* #define SYSCLK_FREQ_24MHz  24000000 */ 
/* #define SYSCLK_FREQ_36MHz  36000000 */
/* #define SYSCLK_FREQ_48MHz  48000000 */
/* #define SYSCLK_FREQ_56MHz  56000000 */
#define SYSCLK_FREQ_72MHz  72000000
#endif/*!< Uncomment the following line if you need to use external SRAM mountedon STM3210E-EVAL board (STM32 High density and XL-density devices) or on STM32100E-EVAL board (STM32 High-density value line devices) as data memory */ 
#if defined (STM32F10X_HD) || (defined STM32F10X_XL) || (defined STM32F10X_HD_VL)
/* #define DATA_IN_ExtSRAM */
#endif/*!< Uncomment the following line if you need to relocate your vector Table inInternal SRAM. */ 
/* #define VECT_TAB_SRAM */
#define VECT_TAB_OFFSET  0x0 /*!< Vector Table base offset field. This value must be a multiple of 0x200. *//*** @}*//** @addtogroup STM32F10x_System_Private_Macros* @{*//*** @}*//** @addtogroup STM32F10x_System_Private_Variables* @{*//*******************************************************************************
*  Clock Definitions
*******************************************************************************/
#ifdef SYSCLK_FREQ_HSEuint32_t SystemCoreClock         = SYSCLK_FREQ_HSE;        /*!< System Clock Frequency (Core Clock) */
#elif defined SYSCLK_FREQ_24MHzuint32_t SystemCoreClock         = SYSCLK_FREQ_24MHz;        /*!< System Clock Frequency (Core Clock) */
#elif defined SYSCLK_FREQ_36MHzuint32_t SystemCoreClock         = SYSCLK_FREQ_36MHz;        /*!< System Clock Frequency (Core Clock) */
#elif defined SYSCLK_FREQ_48MHzuint32_t SystemCoreClock         = SYSCLK_FREQ_48MHz;        /*!< System Clock Frequency (Core Clock) */
#elif defined SYSCLK_FREQ_56MHzuint32_t SystemCoreClock         = SYSCLK_FREQ_56MHz;        /*!< System Clock Frequency (Core Clock) */
#elif defined SYSCLK_FREQ_72MHzuint32_t SystemCoreClock         = SYSCLK_FREQ_72MHz;        /*!< System Clock Frequency (Core Clock) */
#else /*!< HSI Selected as System Clock source */uint32_t SystemCoreClock         = HSI_VALUE;        /*!< System Clock Frequency (Core Clock) */
#endif__I uint8_t AHBPrescTable[16] = {0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 7, 8, 9};
/*** @}*//** @addtogroup STM32F10x_System_Private_FunctionPrototypes* @{*/static void SetSysClock(void);#ifdef SYSCLK_FREQ_HSEstatic void SetSysClockToHSE(void);
#elif defined SYSCLK_FREQ_24MHzstatic void SetSysClockTo24(void);
#elif defined SYSCLK_FREQ_36MHzstatic void SetSysClockTo36(void);
#elif defined SYSCLK_FREQ_48MHzstatic void SetSysClockTo48(void);
#elif defined SYSCLK_FREQ_56MHzstatic void SetSysClockTo56(void);  
#elif defined SYSCLK_FREQ_72MHzstatic void SetSysClockTo72(void);
#endif#ifdef DATA_IN_ExtSRAMstatic void SystemInit_ExtMemCtl(void); 
#endif /* DATA_IN_ExtSRAM *//*** @}*//** @addtogroup STM32F10x_System_Private_Functions* @{*//*** @brief  Setup the microcontroller system*         Initialize the Embedded Flash Interface, the PLL and update the *         SystemCoreClock variable.* @note   This function should be used only after reset.* @param  None* @retval None*/
void SystemInit (void)
{
#ifdef USE_HSE_CLOCK	/* Reset the RCC clock configuration to the default reset state(for debug purpose) *//* Set HSION bit */RCC->CR |= (uint32_t)0x00000001;/* Reset SW, HPRE, PPRE1, PPRE2, ADCPRE and MCO bits */
#ifndef STM32F10X_CLRCC->CFGR &= (uint32_t)0xF8FF0000;
#elseRCC->CFGR &= (uint32_t)0xF0FF0000;
#endif /* STM32F10X_CL */   /* Reset HSEON, CSSON and PLLON bits */RCC->CR &= (uint32_t)0xFEF6FFFF;/* Reset HSEBYP bit */RCC->CR &= (uint32_t)0xFFFBFFFF;/* Reset PLLSRC, PLLXTPRE, PLLMUL and USBPRE/OTGFSPRE bits */RCC->CFGR &= (uint32_t)0xFF80FFFF;#ifdef STM32F10X_CL/* Reset PLL2ON and PLL3ON bits */RCC->CR &= (uint32_t)0xEBFFFFFF;/* Disable all interrupts and clear pending bits  */RCC->CIR = 0x00FF0000;/* Reset CFGR2 register */RCC->CFGR2 = 0x00000000;
#elif defined (STM32F10X_LD_VL) || defined (STM32F10X_MD_VL) || (defined STM32F10X_HD_VL)/* Disable all interrupts and clear pending bits  */RCC->CIR = 0x009F0000;/* Reset CFGR2 register */RCC->CFGR2 = 0x00000000;      
#else/* Disable all interrupts and clear pending bits  */RCC->CIR = 0x009F0000;
#endif /* STM32F10X_CL */#if defined (STM32F10X_HD) || (defined STM32F10X_XL) || (defined STM32F10X_HD_VL)#ifdef DATA_IN_ExtSRAMSystemInit_ExtMemCtl(); #endif /* DATA_IN_ExtSRAM */
#endif /* Configure the System clock frequency, HCLK, PCLK2 and PCLK1 prescalers *//* Configure the Flash Latency cycles and enable prefetch buffer */SetSysClock();#ifdef VECT_TAB_SRAMSCB->VTOR = SRAM_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal SRAM. */
#elseSCB->VTOR = FLASH_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal FLASH. */
#endif 
#else
/* 开启HSI 即内部晶振时钟 */RCC->CR |= (uint32_t)0x00000001; 
//  RCC_DeInit();
//  RCC_HSEConfig(RCC_HSE_ON);  //使能内部时钟 HSI/*选择HSI为PLL的时钟源HSI必须2分频给PLL*/RCC->CFGR |= (uint32_t)RCC_CFGR_PLLSRC_HSI_Div2; /*PLLCLK=8/2*9=36MHz   设置倍频得到时钟源PLL的频率*/RCC->CFGR |= (uint32_t)RCC_CFGR_PLLMULL9;/* PLL不分频输出  */RCC->CFGR |= (uint32_t)RCC_CFGR_HPRE_DIV1;/* 使能 PLL时钟 */RCC->CR |= RCC_CR_PLLON;/* 等待PLL时钟就绪*/while((RCC->CR & RCC_CR_PLLRDY) == 0){}/* 选择PLL为系统时钟的时钟源 */RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_SW));RCC->CFGR |= (uint32_t)RCC_CFGR_SW_PLL;    /* 等到PLL成为系统时钟的时钟源*/while ((RCC->CFGR & (uint32_t)RCC_CFGR_SWS) != (uint32_t)0x08){}	
#endif	
}/*** @brief  Update SystemCoreClock variable according to Clock Register Values.*         The SystemCoreClock variable contains the core clock (HCLK), it can*         be used by the user application to setup the SysTick timer or configure*         other parameters.*           * @note   Each time the core clock (HCLK) changes, this function must be called*         to update SystemCoreClock variable value. Otherwise, any configuration*         based on this variable will be incorrect.         *     * @note   - The system frequency computed by this function is not the real *           frequency in the chip. It is calculated based on the predefined *           constant and the selected clock source:*             *           - If SYSCLK source is HSI, SystemCoreClock will contain the HSI_VALUE(*)*                                              *           - If SYSCLK source is HSE, SystemCoreClock will contain the HSE_VALUE(**)*                          *           - If SYSCLK source is PLL, SystemCoreClock will contain the HSE_VALUE(**) *             or HSI_VALUE(*) multiplied by the PLL factors.*         *         (*) HSI_VALUE is a constant defined in stm32f1xx.h file (default value*             8 MHz) but the real value may vary depending on the variations*             in voltage and temperature.   *    *         (**) HSE_VALUE is a constant defined in stm32f1xx.h file (default value*              8 MHz or 25 MHz, depedning on the product used), user has to ensure*              that HSE_VALUE is same as the real frequency of the crystal used.*              Otherwise, this function may have wrong result.*                *         - The result of this function could be not correct when using fractional*           value for HSE crystal.* @param  None* @retval None*/
void SystemCoreClockUpdate (void)
{uint32_t tmp = 0, pllmull = 0, pllsource = 0;#ifdef  STM32F10X_CLuint32_t prediv1source = 0, prediv1factor = 0, prediv2factor = 0, pll2mull = 0;
#endif /* STM32F10X_CL */#if defined (STM32F10X_LD_VL) || defined (STM32F10X_MD_VL) || (defined STM32F10X_HD_VL)uint32_t prediv1factor = 0;
#endif /* STM32F10X_LD_VL or STM32F10X_MD_VL or STM32F10X_HD_VL *//* Get SYSCLK source -------------------------------------------------------*/tmp = RCC->CFGR & RCC_CFGR_SWS;switch (tmp){case 0x00:  /* HSI used as system clock */SystemCoreClock = HSI_VALUE;break;case 0x04:  /* HSE used as system clock */SystemCoreClock = HSE_VALUE;break;case 0x08:  /* PLL used as system clock *//* Get PLL clock source and multiplication factor ----------------------*/pllmull = RCC->CFGR & RCC_CFGR_PLLMULL;pllsource = RCC->CFGR & RCC_CFGR_PLLSRC;#ifndef STM32F10X_CL      pllmull = ( pllmull >> 18) + 2;if (pllsource == 0x00){/* HSI oscillator clock divided by 2 selected as PLL clock entry */SystemCoreClock = (HSI_VALUE >> 1) * pllmull;}else{#if defined (STM32F10X_LD_VL) || defined (STM32F10X_MD_VL) || (defined STM32F10X_HD_VL)prediv1factor = (RCC->CFGR2 & RCC_CFGR2_PREDIV1) + 1;/* HSE oscillator clock selected as PREDIV1 clock entry */SystemCoreClock = (HSE_VALUE / prediv1factor) * pllmull; #else/* HSE selected as PLL clock entry */if ((RCC->CFGR & RCC_CFGR_PLLXTPRE) != (uint32_t)RESET){/* HSE oscillator clock divided by 2 */SystemCoreClock = (HSE_VALUE >> 1) * pllmull;}else{SystemCoreClock = HSE_VALUE * pllmull;}#endif}
#elsepllmull = pllmull >> 18;if (pllmull != 0x0D){pllmull += 2;}else{ /* PLL multiplication factor = PLL input clock * 6.5 */pllmull = 13 / 2; }if (pllsource == 0x00){/* HSI oscillator clock divided by 2 selected as PLL clock entry */SystemCoreClock = (HSI_VALUE >> 1) * pllmull;}else{/* PREDIV1 selected as PLL clock entry *//* Get PREDIV1 clock source and division factor */prediv1source = RCC->CFGR2 & RCC_CFGR2_PREDIV1SRC;prediv1factor = (RCC->CFGR2 & RCC_CFGR2_PREDIV1) + 1;if (prediv1source == 0){ /* HSE oscillator clock selected as PREDIV1 clock entry */SystemCoreClock = (HSE_VALUE / prediv1factor) * pllmull;          }else{/* PLL2 clock selected as PREDIV1 clock entry *//* Get PREDIV2 division factor and PLL2 multiplication factor */prediv2factor = ((RCC->CFGR2 & RCC_CFGR2_PREDIV2) >> 4) + 1;pll2mull = ((RCC->CFGR2 & RCC_CFGR2_PLL2MUL) >> 8 ) + 2; SystemCoreClock = (((HSE_VALUE / prediv2factor) * pll2mull) / prediv1factor) * pllmull;                         }}
#endif /* STM32F10X_CL */ break;default:SystemCoreClock = HSI_VALUE;break;}/* Compute HCLK clock frequency ----------------*//* Get HCLK prescaler */tmp = AHBPrescTable[((RCC->CFGR & RCC_CFGR_HPRE) >> 4)];/* HCLK clock frequency */SystemCoreClock >>= tmp;  
}/*** @brief  Configures the System clock frequency, HCLK, PCLK2 and PCLK1 prescalers.* @param  None* @retval None*/
static void SetSysClock(void)
{
#ifdef SYSCLK_FREQ_HSESetSysClockToHSE();
#elif defined SYSCLK_FREQ_24MHzSetSysClockTo24();
#elif defined SYSCLK_FREQ_36MHzSetSysClockTo36();
#elif defined SYSCLK_FREQ_48MHzSetSysClockTo48();
#elif defined SYSCLK_FREQ_56MHzSetSysClockTo56();  
#elif defined SYSCLK_FREQ_72MHzSetSysClockTo72();
#endif/* If none of the define above is enabled, the HSI is used as System clocksource (default after reset) */ 
}/*** @brief  Setup the external memory controller. Called in startup_stm32f10x.s *          before jump to __main* @param  None* @retval None*/ 
#ifdef DATA_IN_ExtSRAM
/*** @brief  Setup the external memory controller. *         Called in startup_stm32f10x_xx.s/.c before jump to main.* 	      This function configures the external SRAM mounted on STM3210E-EVAL*         board (STM32 High density devices). This SRAM will be used as program*         data memory (including heap and stack).* @param  None* @retval None*/ 
void SystemInit_ExtMemCtl(void) 
{
/*!< FSMC Bank1 NOR/SRAM3 is used for the STM3210E-EVAL, if another Bank is required, then adjust the Register Addresses *//* Enable FSMC clock */RCC->AHBENR = 0x00000114;/* Enable GPIOD, GPIOE, GPIOF and GPIOG clocks */  RCC->APB2ENR = 0x000001E0;/* ---------------  SRAM Data lines, NOE and NWE configuration ---------------*/
/*----------------  SRAM Address lines configuration -------------------------*/
/*----------------  NOE and NWE configuration --------------------------------*/  
/*----------------  NE3 configuration ----------------------------------------*/
/*----------------  NBL0, NBL1 configuration ---------------------------------*/GPIOD->CRL = 0x44BB44BB;  GPIOD->CRH = 0xBBBBBBBB;GPIOE->CRL = 0xB44444BB;  GPIOE->CRH = 0xBBBBBBBB;GPIOF->CRL = 0x44BBBBBB;  GPIOF->CRH = 0xBBBB4444;GPIOG->CRL = 0x44BBBBBB;  GPIOG->CRH = 0x44444B44;/*----------------  FSMC Configuration ---------------------------------------*/  
/*----------------  Enable FSMC Bank1_SRAM Bank ------------------------------*/FSMC_Bank1->BTCR[4] = 0x00001011;FSMC_Bank1->BTCR[5] = 0x00000200;
}
#endif /* DATA_IN_ExtSRAM */#ifdef SYSCLK_FREQ_HSE
/*** @brief  Selects HSE as System clock source and configure HCLK, PCLK2*         and PCLK1 prescalers.* @note   This function should be used only after reset.* @param  None* @retval None*/
static void SetSysClockToHSE(void)
{__IO uint32_t StartUpCounter = 0, HSEStatus = 0;/* SYSCLK, HCLK, PCLK2 and PCLK1 configuration ---------------------------*/    /* Enable HSE */    RCC->CR |= ((uint32_t)RCC_CR_HSEON);/* Wait till HSE is ready and if Time out is reached exit */do{HSEStatus = RCC->CR & RCC_CR_HSERDY;StartUpCounter++;  } while((HSEStatus == 0) && (StartUpCounter != HSE_STARTUP_TIMEOUT));if ((RCC->CR & RCC_CR_HSERDY) != RESET){HSEStatus = (uint32_t)0x01;}else{HSEStatus = (uint32_t)0x00;}  if (HSEStatus == (uint32_t)0x01){#if !defined STM32F10X_LD_VL && !defined STM32F10X_MD_VL && !defined STM32F10X_HD_VL/* Enable Prefetch Buffer */FLASH->ACR |= FLASH_ACR_PRFTBE;/* Flash 0 wait state */FLASH->ACR &= (uint32_t)((uint32_t)~FLASH_ACR_LATENCY);#ifndef STM32F10X_CLFLASH->ACR |= (uint32_t)FLASH_ACR_LATENCY_0;
#elseif (HSE_VALUE <= 24000000){FLASH->ACR |= (uint32_t)FLASH_ACR_LATENCY_0;}else{FLASH->ACR |= (uint32_t)FLASH_ACR_LATENCY_1;}
#endif /* STM32F10X_CL */
#endif/* HCLK = SYSCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_HPRE_DIV1;/* PCLK2 = HCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE2_DIV1;/* PCLK1 = HCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE1_DIV1;/* Select HSE as system clock source */RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_SW));RCC->CFGR |= (uint32_t)RCC_CFGR_SW_HSE;    /* Wait till HSE is used as system clock source */while ((RCC->CFGR & (uint32_t)RCC_CFGR_SWS) != (uint32_t)0x04){}}else{ /* If HSE fails to start-up, the application will have wrong clock configuration. User can add here some code to deal with this error */}  
}
#elif defined SYSCLK_FREQ_24MHz
/*** @brief  Sets System clock frequency to 24MHz and configure HCLK, PCLK2 *         and PCLK1 prescalers.* @note   This function should be used only after reset.* @param  None* @retval None*/
static void SetSysClockTo24(void)
{__IO uint32_t StartUpCounter = 0, HSEStatus = 0;/* SYSCLK, HCLK, PCLK2 and PCLK1 configuration ---------------------------*/    /* Enable HSE */    RCC->CR |= ((uint32_t)RCC_CR_HSEON);/* Wait till HSE is ready and if Time out is reached exit */do{HSEStatus = RCC->CR & RCC_CR_HSERDY;StartUpCounter++;  } while((HSEStatus == 0) && (StartUpCounter != HSE_STARTUP_TIMEOUT));if ((RCC->CR & RCC_CR_HSERDY) != RESET){HSEStatus = (uint32_t)0x01;}else{HSEStatus = (uint32_t)0x00;}  if (HSEStatus == (uint32_t)0x01){
#if !defined STM32F10X_LD_VL && !defined STM32F10X_MD_VL && !defined STM32F10X_HD_VL /* Enable Prefetch Buffer */FLASH->ACR |= FLASH_ACR_PRFTBE;/* Flash 0 wait state */FLASH->ACR &= (uint32_t)((uint32_t)~FLASH_ACR_LATENCY);FLASH->ACR |= (uint32_t)FLASH_ACR_LATENCY_0;    
#endif/* HCLK = SYSCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_HPRE_DIV1;/* PCLK2 = HCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE2_DIV1;/* PCLK1 = HCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE1_DIV1;#ifdef STM32F10X_CL/* Configure PLLs ------------------------------------------------------*//* PLL configuration: PLLCLK = PREDIV1 * 6 = 24 MHz */ RCC->CFGR &= (uint32_t)~(RCC_CFGR_PLLXTPRE | RCC_CFGR_PLLSRC | RCC_CFGR_PLLMULL);RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLXTPRE_PREDIV1 | RCC_CFGR_PLLSRC_PREDIV1 | RCC_CFGR_PLLMULL6); /* PLL2 configuration: PLL2CLK = (HSE / 5) * 8 = 40 MHz *//* PREDIV1 configuration: PREDIV1CLK = PLL2 / 10 = 4 MHz */       RCC->CFGR2 &= (uint32_t)~(RCC_CFGR2_PREDIV2 | RCC_CFGR2_PLL2MUL |RCC_CFGR2_PREDIV1 | RCC_CFGR2_PREDIV1SRC);RCC->CFGR2 |= (uint32_t)(RCC_CFGR2_PREDIV2_DIV5 | RCC_CFGR2_PLL2MUL8 |RCC_CFGR2_PREDIV1SRC_PLL2 | RCC_CFGR2_PREDIV1_DIV10);/* Enable PLL2 */RCC->CR |= RCC_CR_PLL2ON;/* Wait till PLL2 is ready */while((RCC->CR & RCC_CR_PLL2RDY) == 0){}   
#elif defined (STM32F10X_LD_VL) || defined (STM32F10X_MD_VL) || defined (STM32F10X_HD_VL)/*  PLL configuration:  = (HSE / 2) * 6 = 24 MHz */RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_PLLSRC | RCC_CFGR_PLLXTPRE | RCC_CFGR_PLLMULL));RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLSRC_PREDIV1 | RCC_CFGR_PLLXTPRE_PREDIV1_Div2 | RCC_CFGR_PLLMULL6);
#else    /*  PLL configuration:  = (HSE / 2) * 6 = 24 MHz */RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_PLLSRC | RCC_CFGR_PLLXTPRE | RCC_CFGR_PLLMULL));RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLSRC_HSE | RCC_CFGR_PLLXTPRE_HSE_Div2 | RCC_CFGR_PLLMULL6);
#endif /* STM32F10X_CL *//* Enable PLL */RCC->CR |= RCC_CR_PLLON;/* Wait till PLL is ready */while((RCC->CR & RCC_CR_PLLRDY) == 0){}/* Select PLL as system clock source */RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_SW));RCC->CFGR |= (uint32_t)RCC_CFGR_SW_PLL;    /* Wait till PLL is used as system clock source */while ((RCC->CFGR & (uint32_t)RCC_CFGR_SWS) != (uint32_t)0x08){}}else{ /* If HSE fails to start-up, the application will have wrong clock configuration. User can add here some code to deal with this error */} 
}
#elif defined SYSCLK_FREQ_36MHz
/*** @brief  Sets System clock frequency to 36MHz and configure HCLK, PCLK2 *         and PCLK1 prescalers. * @note   This function should be used only after reset.* @param  None* @retval None*/
static void SetSysClockTo36(void)
{__IO uint32_t StartUpCounter = 0, HSEStatus = 0;/* SYSCLK, HCLK, PCLK2 and PCLK1 configuration ---------------------------*/    /* Enable HSE */    RCC->CR |= ((uint32_t)RCC_CR_HSEON);/* Wait till HSE is ready and if Time out is reached exit */do{HSEStatus = RCC->CR & RCC_CR_HSERDY;StartUpCounter++;  } while((HSEStatus == 0) && (StartUpCounter != HSE_STARTUP_TIMEOUT));if ((RCC->CR & RCC_CR_HSERDY) != RESET){HSEStatus = (uint32_t)0x01;}else{HSEStatus = (uint32_t)0x00;}  if (HSEStatus == (uint32_t)0x01){/* Enable Prefetch Buffer */FLASH->ACR |= FLASH_ACR_PRFTBE;/* Flash 1 wait state */FLASH->ACR &= (uint32_t)((uint32_t)~FLASH_ACR_LATENCY);FLASH->ACR |= (uint32_t)FLASH_ACR_LATENCY_1;    /* HCLK = SYSCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_HPRE_DIV1;/* PCLK2 = HCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE2_DIV1;/* PCLK1 = HCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE1_DIV1;#ifdef STM32F10X_CL/* Configure PLLs ------------------------------------------------------*//* PLL configuration: PLLCLK = PREDIV1 * 9 = 36 MHz */ RCC->CFGR &= (uint32_t)~(RCC_CFGR_PLLXTPRE | RCC_CFGR_PLLSRC | RCC_CFGR_PLLMULL);RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLXTPRE_PREDIV1 | RCC_CFGR_PLLSRC_PREDIV1 | RCC_CFGR_PLLMULL9); /*!< PLL2 configuration: PLL2CLK = (HSE / 5) * 8 = 40 MHz *//* PREDIV1 configuration: PREDIV1CLK = PLL2 / 10 = 4 MHz */RCC->CFGR2 &= (uint32_t)~(RCC_CFGR2_PREDIV2 | RCC_CFGR2_PLL2MUL |RCC_CFGR2_PREDIV1 | RCC_CFGR2_PREDIV1SRC);RCC->CFGR2 |= (uint32_t)(RCC_CFGR2_PREDIV2_DIV5 | RCC_CFGR2_PLL2MUL8 |RCC_CFGR2_PREDIV1SRC_PLL2 | RCC_CFGR2_PREDIV1_DIV10);/* Enable PLL2 */RCC->CR |= RCC_CR_PLL2ON;/* Wait till PLL2 is ready */while((RCC->CR & RCC_CR_PLL2RDY) == 0){}#else    /*  PLL configuration: PLLCLK = (HSE / 2) * 9 = 36 MHz */RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_PLLSRC | RCC_CFGR_PLLXTPRE | RCC_CFGR_PLLMULL));RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLSRC_HSE | RCC_CFGR_PLLXTPRE_HSE_Div2 | RCC_CFGR_PLLMULL9);
#endif /* STM32F10X_CL *//* Enable PLL */RCC->CR |= RCC_CR_PLLON;/* Wait till PLL is ready */while((RCC->CR & RCC_CR_PLLRDY) == 0){}/* Select PLL as system clock source */RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_SW));RCC->CFGR |= (uint32_t)RCC_CFGR_SW_PLL;    /* Wait till PLL is used as system clock source */while ((RCC->CFGR & (uint32_t)RCC_CFGR_SWS) != (uint32_t)0x08){}}else{ /* If HSE fails to start-up, the application will have wrong clock configuration. User can add here some code to deal with this error */} 
}
#elif defined SYSCLK_FREQ_48MHz
/*** @brief  Sets System clock frequency to 48MHz and configure HCLK, PCLK2 *         and PCLK1 prescalers. * @note   This function should be used only after reset.* @param  None* @retval None*/
static void SetSysClockTo48(void)
{__IO uint32_t StartUpCounter = 0, HSEStatus = 0;/* SYSCLK, HCLK, PCLK2 and PCLK1 configuration ---------------------------*/    /* Enable HSE */    RCC->CR |= ((uint32_t)RCC_CR_HSEON);/* Wait till HSE is ready and if Time out is reached exit */do{HSEStatus = RCC->CR & RCC_CR_HSERDY;StartUpCounter++;  } while((HSEStatus == 0) && (StartUpCounter != HSE_STARTUP_TIMEOUT));if ((RCC->CR & RCC_CR_HSERDY) != RESET){HSEStatus = (uint32_t)0x01;}else{HSEStatus = (uint32_t)0x00;}  if (HSEStatus == (uint32_t)0x01){/* Enable Prefetch Buffer */FLASH->ACR |= FLASH_ACR_PRFTBE;/* Flash 1 wait state */FLASH->ACR &= (uint32_t)((uint32_t)~FLASH_ACR_LATENCY);FLASH->ACR |= (uint32_t)FLASH_ACR_LATENCY_1;    /* HCLK = SYSCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_HPRE_DIV1;/* PCLK2 = HCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE2_DIV1;/* PCLK1 = HCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE1_DIV2;#ifdef STM32F10X_CL/* Configure PLLs ------------------------------------------------------*//* PLL2 configuration: PLL2CLK = (HSE / 5) * 8 = 40 MHz *//* PREDIV1 configuration: PREDIV1CLK = PLL2 / 5 = 8 MHz */RCC->CFGR2 &= (uint32_t)~(RCC_CFGR2_PREDIV2 | RCC_CFGR2_PLL2MUL |RCC_CFGR2_PREDIV1 | RCC_CFGR2_PREDIV1SRC);RCC->CFGR2 |= (uint32_t)(RCC_CFGR2_PREDIV2_DIV5 | RCC_CFGR2_PLL2MUL8 |RCC_CFGR2_PREDIV1SRC_PLL2 | RCC_CFGR2_PREDIV1_DIV5);/* Enable PLL2 */RCC->CR |= RCC_CR_PLL2ON;/* Wait till PLL2 is ready */while((RCC->CR & RCC_CR_PLL2RDY) == 0){}/* PLL configuration: PLLCLK = PREDIV1 * 6 = 48 MHz */ RCC->CFGR &= (uint32_t)~(RCC_CFGR_PLLXTPRE | RCC_CFGR_PLLSRC | RCC_CFGR_PLLMULL);RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLXTPRE_PREDIV1 | RCC_CFGR_PLLSRC_PREDIV1 | RCC_CFGR_PLLMULL6); 
#else    /*  PLL configuration: PLLCLK = HSE * 6 = 48 MHz */RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_PLLSRC | RCC_CFGR_PLLXTPRE | RCC_CFGR_PLLMULL));RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLSRC_HSE | RCC_CFGR_PLLMULL6);
#endif /* STM32F10X_CL *//* Enable PLL */RCC->CR |= RCC_CR_PLLON;/* Wait till PLL is ready */while((RCC->CR & RCC_CR_PLLRDY) == 0){}/* Select PLL as system clock source */RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_SW));RCC->CFGR |= (uint32_t)RCC_CFGR_SW_PLL;    /* Wait till PLL is used as system clock source */while ((RCC->CFGR & (uint32_t)RCC_CFGR_SWS) != (uint32_t)0x08){}}else{ /* If HSE fails to start-up, the application will have wrong clock configuration. User can add here some code to deal with this error */} 
}#elif defined SYSCLK_FREQ_56MHz
/*** @brief  Sets System clock frequency to 56MHz and configure HCLK, PCLK2 *         and PCLK1 prescalers. * @note   This function should be used only after reset.* @param  None* @retval None*/
static void SetSysClockTo56(void)
{__IO uint32_t StartUpCounter = 0, HSEStatus = 0;/* SYSCLK, HCLK, PCLK2 and PCLK1 configuration ---------------------------*/   /* Enable HSE */    RCC->CR |= ((uint32_t)RCC_CR_HSEON);/* Wait till HSE is ready and if Time out is reached exit */do{HSEStatus = RCC->CR & RCC_CR_HSERDY;StartUpCounter++;  } while((HSEStatus == 0) && (StartUpCounter != HSE_STARTUP_TIMEOUT));if ((RCC->CR & RCC_CR_HSERDY) != RESET){HSEStatus = (uint32_t)0x01;}else{HSEStatus = (uint32_t)0x00;}  if (HSEStatus == (uint32_t)0x01){/* Enable Prefetch Buffer */FLASH->ACR |= FLASH_ACR_PRFTBE;/* Flash 2 wait state */FLASH->ACR &= (uint32_t)((uint32_t)~FLASH_ACR_LATENCY);FLASH->ACR |= (uint32_t)FLASH_ACR_LATENCY_2;    /* HCLK = SYSCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_HPRE_DIV1;/* PCLK2 = HCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE2_DIV1;/* PCLK1 = HCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE1_DIV2;#ifdef STM32F10X_CL/* Configure PLLs ------------------------------------------------------*//* PLL2 configuration: PLL2CLK = (HSE / 5) * 8 = 40 MHz *//* PREDIV1 configuration: PREDIV1CLK = PLL2 / 5 = 8 MHz */RCC->CFGR2 &= (uint32_t)~(RCC_CFGR2_PREDIV2 | RCC_CFGR2_PLL2MUL |RCC_CFGR2_PREDIV1 | RCC_CFGR2_PREDIV1SRC);RCC->CFGR2 |= (uint32_t)(RCC_CFGR2_PREDIV2_DIV5 | RCC_CFGR2_PLL2MUL8 |RCC_CFGR2_PREDIV1SRC_PLL2 | RCC_CFGR2_PREDIV1_DIV5);/* Enable PLL2 */RCC->CR |= RCC_CR_PLL2ON;/* Wait till PLL2 is ready */while((RCC->CR & RCC_CR_PLL2RDY) == 0){}/* PLL configuration: PLLCLK = PREDIV1 * 7 = 56 MHz */ RCC->CFGR &= (uint32_t)~(RCC_CFGR_PLLXTPRE | RCC_CFGR_PLLSRC | RCC_CFGR_PLLMULL);RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLXTPRE_PREDIV1 | RCC_CFGR_PLLSRC_PREDIV1 | RCC_CFGR_PLLMULL7); 
#else     /* PLL configuration: PLLCLK = HSE * 7 = 56 MHz */RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_PLLSRC | RCC_CFGR_PLLXTPRE | RCC_CFGR_PLLMULL));RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLSRC_HSE | RCC_CFGR_PLLMULL7);#endif /* STM32F10X_CL *//* Enable PLL */RCC->CR |= RCC_CR_PLLON;/* Wait till PLL is ready */while((RCC->CR & RCC_CR_PLLRDY) == 0){}/* Select PLL as system clock source */RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_SW));RCC->CFGR |= (uint32_t)RCC_CFGR_SW_PLL;    /* Wait till PLL is used as system clock source */while ((RCC->CFGR & (uint32_t)RCC_CFGR_SWS) != (uint32_t)0x08){}}else{ /* If HSE fails to start-up, the application will have wrong clock configuration. User can add here some code to deal with this error */} 
}#elif defined SYSCLK_FREQ_72MHz
/*** @brief  Sets System clock frequency to 72MHz and configure HCLK, PCLK2 *         and PCLK1 prescalers. * @note   This function should be used only after reset.* @param  None* @retval None*/
static void SetSysClockTo72(void)
{__IO uint32_t StartUpCounter = 0, HSEStatus = 0;/* SYSCLK, HCLK, PCLK2 and PCLK1 configuration ---------------------------*/    /* Enable HSE */    RCC->CR |= ((uint32_t)RCC_CR_HSEON);/* Wait till HSE is ready and if Time out is reached exit */do{HSEStatus = RCC->CR & RCC_CR_HSERDY;StartUpCounter++;  } while((HSEStatus == 0) && (StartUpCounter != HSE_STARTUP_TIMEOUT));if ((RCC->CR & RCC_CR_HSERDY) != RESET){HSEStatus = (uint32_t)0x01;}else{HSEStatus = (uint32_t)0x00;}  if (HSEStatus == (uint32_t)0x01){/* Enable Prefetch Buffer */FLASH->ACR |= FLASH_ACR_PRFTBE;/* Flash 2 wait state */FLASH->ACR &= (uint32_t)((uint32_t)~FLASH_ACR_LATENCY);FLASH->ACR |= (uint32_t)FLASH_ACR_LATENCY_2;    /* HCLK = SYSCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_HPRE_DIV1;/* PCLK2 = HCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE2_DIV1;/* PCLK1 = HCLK */RCC->CFGR |= (uint32_t)RCC_CFGR_PPRE1_DIV2;#ifdef STM32F10X_CL/* Configure PLLs ------------------------------------------------------*//* PLL2 configuration: PLL2CLK = (HSE / 5) * 8 = 40 MHz *//* PREDIV1 configuration: PREDIV1CLK = PLL2 / 5 = 8 MHz */RCC->CFGR2 &= (uint32_t)~(RCC_CFGR2_PREDIV2 | RCC_CFGR2_PLL2MUL |RCC_CFGR2_PREDIV1 | RCC_CFGR2_PREDIV1SRC);RCC->CFGR2 |= (uint32_t)(RCC_CFGR2_PREDIV2_DIV5 | RCC_CFGR2_PLL2MUL8 |RCC_CFGR2_PREDIV1SRC_PLL2 | RCC_CFGR2_PREDIV1_DIV5);/* Enable PLL2 */RCC->CR |= RCC_CR_PLL2ON;/* Wait till PLL2 is ready */while((RCC->CR & RCC_CR_PLL2RDY) == 0){}/* PLL configuration: PLLCLK = PREDIV1 * 9 = 72 MHz */ RCC->CFGR &= (uint32_t)~(RCC_CFGR_PLLXTPRE | RCC_CFGR_PLLSRC | RCC_CFGR_PLLMULL);RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLXTPRE_PREDIV1 | RCC_CFGR_PLLSRC_PREDIV1 | RCC_CFGR_PLLMULL9); 
#else    /*  PLL configuration: PLLCLK = HSE * 9 = 72 MHz */RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_PLLSRC | RCC_CFGR_PLLXTPRE |RCC_CFGR_PLLMULL));RCC->CFGR |= (uint32_t)(RCC_CFGR_PLLSRC_HSE | RCC_CFGR_PLLMULL9);
#endif /* STM32F10X_CL *//* Enable PLL */RCC->CR |= RCC_CR_PLLON;/* Wait till PLL is ready */while((RCC->CR & RCC_CR_PLLRDY) == 0){}/* Select PLL as system clock source */RCC->CFGR &= (uint32_t)((uint32_t)~(RCC_CFGR_SW));RCC->CFGR |= (uint32_t)RCC_CFGR_SW_PLL;    /* Wait till PLL is used as system clock source */while ((RCC->CFGR & (uint32_t)RCC_CFGR_SWS) != (uint32_t)0x08){}}else{ /* If HSE fails to start-up, the application will have wrong clock configuration. User can add here some code to deal with this error */}
}
#endif/*** @}*//*** @}*//*** @}*/    
/******************* (C) COPYRIGHT 2011 STMicroelectronics *****END OF FILE****/