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/******************** (C) COPYRIGHT 2007 STMicroelectronics ********************

* File Name          : stm32f10x_rcc.c

* Author             : MCD Application Team

* Date First Issued  : 09/29/2006

* Description        : This file provides all the RCC firmware functions.

********************************************************************************

* History:

* 04/02/2007: V0.2

* 02/05/2007: V0.1

* 09/29/2006: V0.01

********************************************************************************

* THE PRESENT SOFTWARE 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 SOFTWARE AND/OR THE USE MADE BY CUSTOMERS OF THE CODING

* INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.

*******************************************************************************/

/* Includes ------------------------------------------------------------------*/

#include "stm32f10x_rcc.h"

/* Private typedef -----------------------------------------------------------*/

/* Private define ------------------------------------------------------------*/

/* ------------ RCC registers bit address in the alias region ----------- */

#define RCC_OFFSET                (RCC_BASE - PERIPH_BASE)

/* --- CR Register ---*/

/* Alias word address of HSION bit */

#define CR_OFFSET                 (RCC_OFFSET + 0x00)

#define HSION_BitNumber           0x00

#define CR_HSION_BB               (PERIPH_BB_BASE + (CR_OFFSET * 32) + (HSION_BitNumber * 4))

/* Alias word address of PLLON bit */

#define PLLON_BitNumber           0x18

#define CR_PLLON_BB               (PERIPH_BB_BASE + (CR_OFFSET * 32) + (PLLON_BitNumber * 4))

/* Alias word address of CSSON bit */

#define CSSON_BitNumber           0x13

#define CR_CSSON_BB               (PERIPH_BB_BASE + (CR_OFFSET * 32) + (CSSON_BitNumber * 4))

/* --- CFGR Register ---*/

/* Alias word address of USBPRE bit */

#define CFGR_OFFSET               (RCC_OFFSET + 0x04)

#define USBPRE_BitNumber          0x16

#define CFGR_USBPRE_BB            (PERIPH_BB_BASE + (CFGR_OFFSET * 32) + (USBPRE_BitNumber * 4))

/* --- BDCR Register ---*/

/* Alias word address of RTCEN bit */

#define BDCR_OFFSET               (RCC_OFFSET + 0x20)

#define RTCEN_BitNumber           0x0F

#define BDCR_RTCEN_BB             (PERIPH_BB_BASE + (BDCR_OFFSET * 32) + (RTCEN_BitNumber * 4))

/* Alias word address of BDRST bit */

#define BDRST_BitNumber           0x10

#define BDCR_BDRST_BB             (PERIPH_BB_BASE + (BDCR_OFFSET * 32) + (BDRST_BitNumber * 4))

/* --- CSR Register ---*/

/* Alias word address of LSION bit */

#define CSR_OFFSET                (RCC_OFFSET + 0x24)

#define LSION_BitNumber           0x00

#define CSR_LSION_BB              (PERIPH_BB_BASE + (CSR_OFFSET * 32) + (LSION_BitNumber * 4))

/* ---------------------- RCC registers bit mask ------------------------ */

/* CR register bit mask */

#define CR_HSEBYP_Reset           ((u32)0xFFFBFFFF)

#define CR_HSEBYP_Set             ((u32)0x00040000)

#define CR_HSEON_Reset            ((u32)0xFFFEFFFF)

#define CR_HSEON_Set              ((u32)0x00010000)

#define CR_HSITRIM_Mask           ((u32)0xFFFFFF07)

/* CFGR register bit mask */

#define CFGR_PLL_Mask             ((u32)0xFFC0FFFF)

#define CFGR_PLLMull_Mask         ((u32)0x003C0000)

#define CFGR_PLLSRC_Mask          ((u32)0x00010000)

#define CFGR_PLLXTPRE_Mask        ((u32)0x00020000)

#define CFGR_SWS_Mask             ((u32)0x0000000C)

#define CFGR_SW_Mask              ((u32)0xFFFFFFFC)

#define CFGR_HPRE_Reset_Mask      ((u32)0xFFFFFF0F)

#define CFGR_HPRE_Set_Mask        ((u32)0x000000F0)

#define CFGR_PPRE1_Reset_Mask     ((u32)0xFFFFF8FF)

#define CFGR_PPRE1_Set_Mask       ((u32)0x00000700)

#define CFGR_PPRE2_Reset_Mask     ((u32)0xFFFFC7FF)

#define CFGR_PPRE2_Set_Mask       ((u32)0x00003800)

#define CFGR_ADCPRE_Reset_Mask    ((u32)0xFFFF3FFF)

#define CFGR_ADCPRE_Set_Mask      ((u32)0x0000C000)

/* CSR register bit mask */

#define CSR_RVMF_Set              ((u32)0x01000000)

/* RCC Flag Mask */

#define FLAG_Mask                 ((u8)0x1F)

/* Typical Value of the HSI in Hz */

#define HSI_Value                 ((u32)8000000)

/* BDCR register base address */

#define BDCR_BASE                 (PERIPH_BASE + BDCR_OFFSET)

/* Private macro -------------------------------------------------------------*/

/* Private variables ---------------------------------------------------------*/

static uc8 APBAHBPrescTable[16] = {0, 0, 0, 0, 1, 2, 3, 4, 1, 2, 3, 4, 6, 7, 8, 9};

static uc8 ADCPrescTable[4] = {2, 4, 6, 8};

/* Private function prototypes -----------------------------------------------*/

/* Private functions ---------------------------------------------------------*/

/*******************************************************************************

* Function Name  : RCC_DeInit

* Description    : Deinitializes the RCC peripheral registers to their default

*                  reset values.

*                   - The HSITRIM[4:0] bits in RCC_CR register are not modified

*                     by this function.

*                   - The RCC_BDCR and RCC_CSR registers are not reset by this

*                     function.

* Input          : None

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_DeInit(void)

{

  /* Disable APB2 Peripheral Reset */

  RCC->APB2RSTR = 0x00000000;

  /* Disable APB1 Peripheral Reset */

  RCC->APB1RSTR = 0x00000000;

  /* FLITF and SRAM Clock ON */

  RCC->AHBENR = 0x00000014;

  /* Disable APB2 Peripheral Clock */

  RCC->APB2ENR = 0x00000000;

  /* Disable APB1 Peripheral Clock */

  RCC->APB1ENR = 0x00000000;

  /* Set HSION bit */

  RCC->CR |= (u32)0x00000001;

  /* Reset SW[1:0], HPRE[3:0], PPRE1[2:0], PPRE2[2:0], ADCPRE[1:0] and MCO[2:0] bits*/

  RCC->CFGR &= 0xF8FF0000;

  /* Reset HSEON, CSSON and PLLON bits */

  RCC->CR &= 0xFEF6FFFF;

  /* Reset HSEBYP bit */

  RCC->CR &= 0xFFFBFFFF;

  /* Reset PLLSRC, PLLXTPRE, PLLMUL[3:0] and USBPRE bits */

  RCC->CFGR &= 0xFF80FFFF;

  /* Disable all interrupts */

  RCC->CIR = 0x00000000;

}

/*******************************************************************************

* Function Name  : RCC_HSEConfig

* Description    : Configures the External High Speed oscillator (HSE).

* Input          : - RCC_HSE: specifies the new state of the HSE.

*                    This parameter can be one of the following values:

*                       - RCC_HSE_OFF: HSE oscillator OFF

*                       - RCC_HSE_ON: HSE oscillator ON

*                       - RCC_HSE_Bypass: HSE oscillator bypassed with external

*                         clock

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_HSEConfig(u32 RCC_HSE)

{

  /* Check the parameters */

  assert(IS_RCC_HSE(RCC_HSE));

  /* Reset HSEON and HSEBYP bits before configuring the HSE ------------------*/

  /* Reset HSEON bit */

  RCC->CR &= CR_HSEON_Reset;

  /* Reset HSEBYP bit */

  RCC->CR &= CR_HSEBYP_Reset;

  /* Configure HSE (RCC_HSE_OFF is already covered by the code section above) */

  switch(RCC_HSE)

  {

    case RCC_HSE_ON:

      /* Set HSEON bit */

      RCC->CR |= CR_HSEON_Set;

      break;

    case RCC_HSE_Bypass:

      /* Set HSEBYP and HSEON bits */

      RCC->CR |= CR_HSEBYP_Set | CR_HSEON_Set;

      break;

    default:

      break;

  }

}

/*******************************************************************************

* Function Name  : RCC_AdjustHSICalibrationValue

* Description    : Adjusts the Internal High Speed oscillator (HSI) calibration

*                  value.

* Input          : - HSICalibrationValue: specifies the calibration trimming value.

*                    This parameter must be a number between 0 and 0x1F.

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_AdjustHSICalibrationValue(u8 HSICalibrationValue)

{

  u32 tmpreg = 0;

  /* Check the parameters */

  assert(IS_RCC_CALIBRATION_VALUE(HSICalibrationValue));

  tmpreg = RCC->CR;

  /* Clear HSITRIM[7:3] bits */

  tmpreg &= CR_HSITRIM_Mask;

  /* Set the HSITRIM[7:3] bits according to HSICalibrationValue value */

  tmpreg |= (u32)HSICalibrationValue << 3;

  /* Store the new value */

  RCC->CR = tmpreg;

}

/*******************************************************************************

* Function Name  : RCC_HSICmd

* Description    : Enables or disables the Internal High Speed oscillator (HSI).

*                  HSI can not be stopped if it is used directly or through the

*                  PLL as system clock, or if a Flash programmation is on going.

* Input          : - NewState: new state of the HSI.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_HSICmd(FunctionalState NewState)

{

  /* Check the parameters */

  assert(IS_FUNCTIONAL_STATE(NewState));

  *(vu32 *) CR_HSION_BB = (u32)NewState;

}

/*******************************************************************************

* Function Name  : RCC_PLLConfig

* Description    : Configures the PLL clock source and multiplication factor.

*                  This function must be used only when the PLL is disabled.

* Input          : - RCC_PLLSource: specifies the PLL entry clock source.

*                    This parameter can be one of the following values:

*                       - RCC_PLLSource_HSI_Div2: HSI oscillator clock divided

*                         by 2 selected as PLL clock entry

*                       - RCC_PLLSource_HSE_Div1: HSE oscillator clock selected

*                         as PLL clock entry

*                       - RCC_PLLSource_HSE_Div2: HSE oscillator clock divided

*                         by 2 selected as PLL clock entry

*                  - RCC_PLLMul: specifies the PLL multiplication factor.

*                    This parameter can be RCC_PLLMul_x where x:[2,16]

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_PLLConfig(u32 RCC_PLLSource, u32 RCC_PLLMul)

{

  u32 tmpreg = 0;

  /* Check the parameters */

  assert(IS_RCC_PLL_SOURCE(RCC_PLLSource));

  assert(IS_RCC_PLL_MUL(RCC_PLLMul));

  tmpreg = RCC->CFGR;

  /* Clear PLLSRC, PLLXTPRE and PLLMUL[21:18] bits */

  tmpreg &= CFGR_PLL_Mask;

  /* Set the PLL configuration bits */

  tmpreg |= RCC_PLLSource | RCC_PLLMul;

  /* Store the new value */

  RCC->CFGR = tmpreg;

}

/*******************************************************************************

* Function Name  : RCC_PLLCmd

* Description    : Enables or disables the PLL.

*                  The PLL can not be disabled if it is used as system clock.

* Input          : - NewState: new state of the PLL.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_PLLCmd(FunctionalState NewState)

{

  /* Check the parameters */

  assert(IS_FUNCTIONAL_STATE(NewState));

  *(vu32 *) CR_PLLON_BB = (u32)NewState;

}

/*******************************************************************************

* Function Name  : RCC_SYSCLKConfig

* Description    : Configures the system clock (SYSCLK).

* Input          : - RCC_SYSCLKSource: specifies the clock source used as system

*                    clock. This parameter can be one of the following values:

*                       - RCC_SYSCLKSource_HSI: HSI selected as system clock

*                       - RCC_SYSCLKSource_HSE: HSE selected as system clock

*                       - RCC_SYSCLKSource_PLLCLK: PLL selected as system clock

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_SYSCLKConfig(u32 RCC_SYSCLKSource)

{

  u32 tmpreg = 0;

  /* Check the parameters */

  assert(IS_RCC_SYSCLK_SOURCE(RCC_SYSCLKSource));

  tmpreg = RCC->CFGR;

  /* Clear SW[1:0] bits */

  tmpreg &= CFGR_SW_Mask;

  /* Set SW[1:0] bits according to RCC_SYSCLKSource value */

  tmpreg |= RCC_SYSCLKSource;

  /* Store the new value */

  RCC->CFGR = tmpreg;

}

/*******************************************************************************

* Function Name  : RCC_GetSYSCLKSource

* Description    : Returns the clock source used as system clock.

* Input          : None

* Output         : None

* Return         : The clock source used as system clock. The returned value can

*                  be one of the following:

*                       - 0x00: HSI used as system clock

*                       - 0x04: HSE used as system clock

*                       - 0x08: PLL used as system clock

*******************************************************************************/

u8 RCC_GetSYSCLKSource(void)

{

  return ((u8)(RCC->CFGR & CFGR_SWS_Mask));

}

/*******************************************************************************

* Function Name  : RCC_HCLKConfig

* Description    : Configures the AHB clock (HCLK).

* Input          : - RCC_HCLK: defines the AHB clock. This clock is derived

*                    from the system clock (SYSCLK).

*                    This parameter can be one of the following values:

*                       - RCC_SYSCLK_Div1: AHB clock = SYSCLK

*                       - RCC_SYSCLK_Div2: AHB clock = SYSCLK/2

*                       - RCC_SYSCLK_Div4: AHB clock = SYSCLK/4

*                       - RCC_SYSCLK_Div8: AHB clock = SYSCLK/8

*                       - RCC_SYSCLK_Div16: AHB clock = SYSCLK/16

*                       - RCC_SYSCLK_Div64: AHB clock = SYSCLK/64

*                       - RCC_SYSCLK_Div128: AHB clock = SYSCLK/128

*                       - RCC_SYSCLK_Div256: AHB clock = SYSCLK/256

*                       - RCC_SYSCLK_Div512: AHB clock = SYSCLK/512

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_HCLKConfig(u32 RCC_HCLK)

{

  u32 tmpreg = 0;

  /* Check the parameters */

  assert(IS_RCC_HCLK(RCC_HCLK));

  tmpreg = RCC->CFGR;

  /* Clear HPRE[7:4] bits */

  tmpreg &= CFGR_HPRE_Reset_Mask;

  /* Set HPRE[7:4] bits according to RCC_HCLK value */

  tmpreg |= RCC_HCLK;

  /* Store the new value */

  RCC->CFGR = tmpreg;

}

/*******************************************************************************

* Function Name  : RCC_PCLK1Config

* Description    : Configures the Low Speed APB clock (PCLK1).

* Input          : - RCC_PCLK1: defines the APB1 clock. This clock is derived

*                    from the AHB clock (HCLK).

*                    This parameter can be one of the following values:

*                       - RCC_HCLK_Div1: APB1 clock = HCLK

*                       - RCC_HCLK_Div2: APB1 clock = HCLK/2

*                       - RCC_HCLK_Div4: APB1 clock = HCLK/4

*                       - RCC_HCLK_Div8: APB1 clock = HCLK/8

*                       - RCC_HCLK_Div16: APB1 clock = HCLK/16

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_PCLK1Config(u32 RCC_PCLK1)

{

  u32 tmpreg = 0;

  /* Check the parameters */

  assert(IS_RCC_PCLK(RCC_PCLK1));

  tmpreg = RCC->CFGR;

  /* Clear PPRE1[10:8] bits */

  tmpreg &= CFGR_PPRE1_Reset_Mask;

  /* Set PPRE1[10:8] bits according to RCC_PCLK1 value */

  tmpreg |= RCC_PCLK1;

  /* Store the new value */

  RCC->CFGR = tmpreg;

}

/*******************************************************************************

* Function Name  : RCC_PCLK2Config

* Description    : Configures the High Speed APB clock (PCLK2).

* Input          : - RCC_PCLK2: defines the APB2 clock. This clock is derived

*                    from the AHB clock (HCLK).

*                    This parameter can be one of the following values:

*                       - RCC_HCLK_Div1: APB2 clock = HCLK

*                       - RCC_HCLK_Div2: APB2 clock = HCLK/2

*                       - RCC_HCLK_Div4: APB2 clock = HCLK/4

*                       - RCC_HCLK_Div8: APB2 clock = HCLK/8

*                       - RCC_HCLK_Div16: APB2 clock = HCLK/16

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_PCLK2Config(u32 RCC_PCLK2)

{

  u32 tmpreg = 0;

  /* Check the parameters */

  assert(IS_RCC_PCLK(RCC_PCLK2));

  tmpreg = RCC->CFGR;

  /* Clear PPRE2[13:11] bits */

  tmpreg &= CFGR_PPRE2_Reset_Mask;

  /* Set PPRE2[13:11] bits according to RCC_PCLK2 value */

  tmpreg |= RCC_PCLK2 << 3;

  /* Store the new value */

  RCC->CFGR = tmpreg;

}

/*******************************************************************************

* Function Name  : RCC_ITConfig

* Description    : Enables or disables the specified RCC interrupts.

* Input          : - RCC_IT: specifies the RCC interrupt sources to be enabled

*                    or disabled.

*                    This parameter can be any combination of the following values:

*                       - RCC_IT_LSIRDY: LSI ready interrupt

*                       - RCC_IT_LSERDY: LSE ready interrupt

*                       - RCC_IT_HSIRDY: HSI ready interrupt

*                       - RCC_IT_HSERDY: HSE ready interrupt

*                       - RCC_IT_PLLRDY: PLL ready interrupt

*                  - NewState: new state of the specified RCC interrupts.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_ITConfig(u8 RCC_IT, FunctionalState NewState)

{

  /* Check the parameters */

  assert(IS_RCC_IT(RCC_IT));

  assert(IS_FUNCTIONAL_STATE(NewState));

  if (NewState != DISABLE)

  {

    /* Perform Byte access to RCC_CIR[12:8] bits to enable the selected interrupts */

    *(vu8 *) 0x40021009 |= RCC_IT;

  }

  else

  {

    /* Perform Byte access to RCC_CIR[12:8] bits to disable the selected interrupts */

    *(vu8 *) 0x40021009 &= ~(u32)RCC_IT;

  }

}

/*******************************************************************************

* Function Name  : RCC_USBCLKConfig

* Description    : Configures the USB clock (USBCLK).

* Input          : - RCC_USBCLKSource: specifies the USB clock source. This clock

*                    is derived from the PLL output.

*                    This parameter can be one of the following values:

*                       - RCC_USBCLKSource_PLLCLK_1Div5: PLL clock divided by 1,5

*                         selected as USB clock source

*                       - RCC_USBCLKSource_PLLCLK_Div1: PLL clock selected as USB

*                         clock source

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_USBCLKConfig(u32 RCC_USBCLKSource)

{

  /* Check the parameters */

  assert(IS_RCC_USBCLK_SOURCE(RCC_USBCLKSource));

  *(vu32 *) CFGR_USBPRE_BB = RCC_USBCLKSource;

}

/*******************************************************************************

* Function Name  : RCC_ADCCLKConfig

* Description    : Configures the ADC clock (ADCCLK).

* Input          : - RCC_ADCCLK: defines the ADC clock. This clock is derived

*                    from the APB2 clock (PCLK2).

*                    This parameter can be one of the following values:

*                       - RCC_PCLK2_Div2: ADC clock = PCLK2/2

*                       - RCC_PCLK2_Div4: ADC clock = PCLK2/4

*                       - RCC_PCLK2_Div6: ADC clock = PCLK2/6

*                       - RCC_PCLK2_Div8: ADC clock = PCLK2/8

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_ADCCLKConfig(u32 RCC_ADCCLK)

{

  u32 tmpreg = 0;

  /* Check the parameters */

  assert(IS_RCC_ADCCLK(RCC_ADCCLK));

  tmpreg = RCC->CFGR;

  /* Clear ADCPRE[15:14] bits */

  tmpreg &= CFGR_ADCPRE_Reset_Mask;

  /* Set ADCPRE[15:14] bits according to RCC_ADCCLK value */

  tmpreg |= RCC_ADCCLK;

  /* Store the new value */

  RCC->CFGR = tmpreg;

}

/*******************************************************************************

* Function Name  : RCC_LSEConfig

* Description    : Configures the External Low Speed oscillator (LSE).

* Input          : - RCC_LSE: specifies the new state of the LSE.

*                    This parameter can be one of the following values:

*                       - RCC_LSE_OFF: LSE oscillator OFF

*                       - RCC_LSE_ON: LSE oscillator ON

*                       - RCC_LSE_Bypass: LSE oscillator bypassed with external

*                         clock

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_LSEConfig(u32 RCC_LSE)

{

  /* Check the parameters */

  assert(IS_RCC_LSE(RCC_LSE));

  /* Reset LSEON and LSEBYP bits before configuring the LSE ------------------*/

  /* Reset LSEON bit */

  *(vu8 *) BDCR_BASE = RCC_LSE_OFF;

  /* Reset LSEBYP bit */

  *(vu8 *) BDCR_BASE = RCC_LSE_OFF;

  /* Configure LSE (RCC_LSE_OFF is already covered by the code section above) */

  switch(RCC_LSE)

  {

    case RCC_LSE_ON:

      /* Set LSEON bit */

      *(vu8 *) BDCR_BASE = RCC_LSE_ON;

      break;

    case RCC_LSE_Bypass:

      /* Set LSEBYP and LSEON bits */

      *(vu8 *) BDCR_BASE = RCC_LSE_Bypass | RCC_LSE_ON;

      break;

    default:

      break;

  }

}

/*******************************************************************************

* Function Name  : RCC_LSICmd

* Description    : Enables or disables the Internal Low Speed oscillator (LSI).

*                  LSI can not be disabled if the IWDG is running.

* Input          : - NewState: new state of the LSI.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_LSICmd(FunctionalState NewState)

{

  /* Check the parameters */

  assert(IS_FUNCTIONAL_STATE(NewState));

  *(vu32 *) CSR_LSION_BB = (u32)NewState;

}

/*******************************************************************************

* Function Name  : RCC_RTCCLKConfig

* Description    : Configures the RTC clock (RTCCLK).

*                  Once the RTC clock is selected it can’t be changed unless the

*                  Backup domain is reset.

* Input          : - RCC_RTCCLKSource: specifies the RTC clock source.

*                    This parameter can be one of the following values:

*                       - RCC_RTCCLKSource_LSE: LSE oscillator clock used as RTC

*                         clock

*                       - RCC_RTCCLKSource_LSI: LSI oscillator clock used as RTC

*                         clock

*                       - RCC_RTCCLKSource_HSE_Div128: HSE oscillator clock divided

*                         by 128 used as RTC clock

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_RTCCLKConfig(u32 RCC_RTCCLKSource)

{

  /* Check the parameters */

  assert(IS_RCC_RTCCLK_SOURCE(RCC_RTCCLKSource));

  /* Select the RTC clock source */

  RCC->BDCR |= RCC_RTCCLKSource;

}

/*******************************************************************************

* Function Name  : RCC_RTCCLKCmd

* Description    : Enables or disables the RTC clock.

*                  This function must be used only after the RTC clock was

*                  selected using the RCC_RTCCLKConfig function.

* Input          : - NewState: new state of the RTC clock.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_RTCCLKCmd(FunctionalState NewState)

{

  /* Check the parameters */

  assert(IS_FUNCTIONAL_STATE(NewState));

  *(vu32 *) BDCR_RTCEN_BB = (u32)NewState;

}

/*******************************************************************************

* Function Name  : RCC_GetClocksFreq

* Description    : Returns the frequencies of different on chip clocks.

* Input          : - RCC_Clocks: pointer to a RCC_ClocksTypeDef structure which

*                    will hold the clocks frequencies.

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_GetClocksFreq(RCC_ClocksTypeDef* RCC_Clocks)

{

  u32 tmp = 0, pllmull = 0, pllsource = 0, presc = 0;

  /* Get SYSCLK source -------------------------------------------------------*/

  tmp = RCC->CFGR & CFGR_SWS_Mask;

  switch (tmp)

  {

    case 0x00:  /* HSI used as system clock */

      RCC_Clocks->SYSCLK_Frequency = HSI_Value;

      break;

    case 0x04:  /* HSE used as system clock */

      RCC_Clocks->SYSCLK_Frequency = HSE_Value;

      break;

    case 0x08:  /* PLL used as system clock */

      /* Get PLL clock source and multiplication factor ----------------------*/

      pllmull = RCC->CFGR & CFGR_PLLMull_Mask;

      pllmull = ( pllmull >> 18) + 2;

      pllsource = RCC->CFGR & CFGR_PLLSRC_Mask;

      if (pllsource == 0x00)

      {/* HSI oscillator clock divided by 2 selected as PLL clock entry */

        RCC_Clocks->SYSCLK_Frequency = (HSI_Value >> 1) * pllmull;

      }

      else

      {/* HSE selected as PLL clock entry */

        if ((RCC->CFGR & CFGR_PLLXTPRE_Mask) != (u32)RESET)

        {/* HSE oscillator clock divided by 2 */

          RCC_Clocks->SYSCLK_Frequency = (HSE_Value >> 1) * pllmull;

        }

        else

        {

          RCC_Clocks->SYSCLK_Frequency = HSE_Value * pllmull;

        }

      }

      break;

    default:

      RCC_Clocks->SYSCLK_Frequency = HSI_Value;

      break;

  }

  /* Compute HCLK, PCLK1, PCLK2 and ADCCLK clocks frequencies ----------------*/

  /* Get HCLK prescaler */

  tmp = RCC->CFGR & CFGR_HPRE_Set_Mask;

  tmp = tmp >> 4;

  presc = APBAHBPrescTable[tmp];

  /* HCLK clock frequency */

  RCC_Clocks->HCLK_Frequency = RCC_Clocks->SYSCLK_Frequency >> presc;

  /* Get PCLK1 prescaler */

  tmp = RCC->CFGR & CFGR_PPRE1_Set_Mask;

  tmp = tmp >> 8;

  presc = APBAHBPrescTable[tmp];

  /* PCLK1 clock frequency */

  RCC_Clocks->PCLK1_Frequency = RCC_Clocks->HCLK_Frequency >> presc;

  /* Get PCLK2 prescaler */

  tmp = RCC->CFGR & CFGR_PPRE2_Set_Mask;

  tmp = tmp >> 11;

  presc = APBAHBPrescTable[tmp];

  /* PCLK2 clock frequency */

  RCC_Clocks->PCLK2_Frequency = RCC_Clocks->HCLK_Frequency >> presc;

  /* Get ADCCLK prescaler */

  tmp = RCC->CFGR & CFGR_ADCPRE_Set_Mask;

  tmp = tmp >> 14;

  presc = ADCPrescTable[tmp];

  /* ADCCLK clock frequency */

  RCC_Clocks->ADCCLK_Frequency = RCC_Clocks->PCLK2_Frequency / presc;

}

/*******************************************************************************

* Function Name  : RCC_AHBPeriphClockCmd

* Description    : Enables or disables the AHB peripheral clock.

* Input          : - RCC_AHBPeriph: specifies the AHB peripheral to gates its clock.

*                    This parameter can be any combination of the following values:

*                       - RCC_AHBPeriph_DMA

*                       - RCC_AHBPeriph_SRAM

*                       - RCC_AHBPeriph_FLITF

*                    SRAM and FLITF clock can be disabled only during sleep mode.

*                  - NewState: new state of the specified peripheral clock.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_AHBPeriphClockCmd(u32 RCC_AHBPeriph, FunctionalState NewState)

{

  /* Check the parameters */

  assert(IS_RCC_AHB_PERIPH(RCC_AHBPeriph));

  assert(IS_FUNCTIONAL_STATE(NewState));

  if (NewState != DISABLE)

  {

    RCC->AHBENR |= RCC_AHBPeriph;

  }

  else

  {

    RCC->AHBENR &= ~RCC_AHBPeriph;

  }

}

/*******************************************************************************

* Function Name  : RCC_APB2PeriphClockCmd

* Description    : Enables or disables the High Speed APB (APB2) peripheral clock.

* Input          : - RCC_APB2Periph: specifies the APB2 peripheral to gates its

*                    clock.

*                    This parameter can be any combination of the following values:

*                       - RCC_APB2Periph_AFIO, RCC_APB2Periph_GPIOA, RCC_APB2Periph_GPIOB

*                         RCC_APB2Periph_GPIOC, RCC_APB2Periph_GPIOD, RCC_APB2Periph_GPIOE

*                         RCC_APB2Periph_ADC1, RCC_APB2Periph_ADC2, RCC_APB2Periph_TIM1

*                         RCC_APB2Periph_SPI1, RCC_APB2Periph_USART1, RCC_APB2Periph_ALL

*                  - NewState: new state of the specified peripheral clock.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_APB2PeriphClockCmd(u32 RCC_APB2Periph, FunctionalState NewState)

{

  /* Check the parameters */

  assert(IS_RCC_APB2_PERIPH(RCC_APB2Periph));

  assert(IS_FUNCTIONAL_STATE(NewState));

  if (NewState != DISABLE)

  {

    RCC->APB2ENR |= RCC_APB2Periph;

  }

  else

  {

    RCC->APB2ENR &= ~RCC_APB2Periph;

  }

}

/*******************************************************************************

* Function Name  : RCC_APB1PeriphClockCmd

* Description    : Enables or disables the Low Speed APB (APB1) peripheral clock.

* Input          : - RCC_APB1Periph: specifies the APB1 peripheral to gates its

*                    clock.

*                    This parameter can be any combination of the following values:

*                       - RCC_APB1Periph_TIM2, RCC_APB1Periph_TIM3, RCC_APB1Periph_TIM4

*                         RCC_APB1Periph_WWDG, RCC_APB1Periph_SPI2, RCC_APB1Periph_USART2

*                         RCC_APB1Periph_USART3, RCC_APB1Periph_I2C1, RCC_APB1Periph_I2C2

*                         RCC_APB1Periph_USB, RCC_APB1Periph_CAN, RCC_APB1Periph_BKP

*                         RCC_APB1Periph_PWR, RCC_APB1Periph_ALL

*                  - NewState: new state of the specified peripheral clock.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None

* Return         : None

*******************************************************************************/

void RCC_APB1PeriphClockCmd(u32 RCC_APB1Periph, FunctionalState NewState)