Simple "hello world" style program for X-NUCLEO-IKS01A1 MEMS Inertial

Dependencies:   BLE_API X_NUCLEO_IDB0XA1 X_NUCLEO_IKS01A1 mbed

Fork of HelloWorld_IKS01A1 by ST

Revision:
8:1c6281289d67
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/stm32f4xx_rcc.c	Sun Nov 15 09:00:40 2015 +0000
@@ -0,0 +1,1809 @@
+/**
+  ******************************************************************************
+  * @file    stm32f4xx_rcc.c
+  * @author  MCD Application Team
+  * @version V1.0.0
+  * @date    30-September-2011
+  * @brief   This file provides firmware functions to manage the following 
+  *          functionalities of the Reset and clock control (RCC) peripheral:
+  *           - Internal/external clocks, PLL, CSS and MCO configuration
+  *           - System, AHB and APB busses clocks configuration
+  *           - Peripheral clocks configuration
+  *           - Interrupts and flags management
+  *
+  *  @verbatim
+  *               
+  *          ===================================================================
+  *                               RCC specific features
+  *          ===================================================================
+  *    
+  *          After reset the device is running from Internal High Speed oscillator 
+  *          (HSI 16MHz) with Flash 0 wait state, Flash prefetch buffer, D-Cache 
+  *          and I-Cache are disabled, and all peripherals are off except internal
+  *          SRAM, Flash and JTAG.
+  *           - There is no prescaler on High speed (AHB) and Low speed (APB) busses;
+  *             all peripherals mapped on these busses are running at HSI speed.
+  *       	  - The clock for all peripherals is switched off, except the SRAM and FLASH.
+  *           - All GPIOs are in input floating state, except the JTAG pins which
+  *             are assigned to be used for debug purpose.
+  *        
+  *          Once the device started from reset, the user application has to:        
+  *           - Configure the clock source to be used to drive the System clock
+  *             (if the application needs higher frequency/performance)
+  *           - Configure the System clock frequency and Flash settings  
+  *           - Configure the AHB and APB busses prescalers
+  *           - Enable the clock for the peripheral(s) to be used
+  *           - Configure the clock source(s) for peripherals which clocks are not
+  *             derived from the System clock (I2S, RTC, ADC, USB OTG FS/SDIO/RNG)      
+  *                        
+  *  @endverbatim
+  *    
+  ******************************************************************************
+  * @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>
+  ******************************************************************************
+  */
+
+/* Includes ------------------------------------------------------------------*/
+#include "stm32f4xx_rcc.h"
+
+/** @addtogroup STM32F4xx_StdPeriph_Driver
+  * @{
+  */
+
+/** @defgroup RCC 
+  * @brief RCC driver modules
+  * @{
+  */ 
+
+/* 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 CSSON bit */
+#define CSSON_BitNumber           0x13
+#define CR_CSSON_BB               (PERIPH_BB_BASE + (CR_OFFSET * 32) + (CSSON_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 PLLI2SON bit */
+#define PLLI2SON_BitNumber        0x1A
+#define CR_PLLI2SON_BB            (PERIPH_BB_BASE + (CR_OFFSET * 32) + (PLLI2SON_BitNumber * 4))
+
+/* --- CFGR Register ---*/
+/* Alias word address of I2SSRC bit */
+#define CFGR_OFFSET               (RCC_OFFSET + 0x08)
+#define I2SSRC_BitNumber          0x17
+#define CFGR_I2SSRC_BB            (PERIPH_BB_BASE + (CFGR_OFFSET * 32) + (I2SSRC_BitNumber * 4))
+
+/* --- BDCR Register ---*/
+/* Alias word address of RTCEN bit */
+#define BDCR_OFFSET               (RCC_OFFSET + 0x70)
+#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 + 0x74)
+#define LSION_BitNumber           0x00
+#define CSR_LSION_BB              (PERIPH_BB_BASE + (CSR_OFFSET * 32) + (LSION_BitNumber * 4))
+/* ---------------------- RCC registers bit mask ------------------------ */
+/* CFGR register bit mask */
+#define CFGR_MCO2_RESET_MASK      ((uint32_t)0x07FFFFFF)
+#define CFGR_MCO1_RESET_MASK      ((uint32_t)0xF89FFFFF)
+
+/* RCC Flag Mask */
+#define FLAG_MASK                 ((uint8_t)0x1F)
+
+/* CR register byte 3 (Bits[23:16]) base address */
+#define CR_BYTE3_ADDRESS          ((uint32_t)0x40023802)
+
+/* CIR register byte 2 (Bits[15:8]) base address */
+#define CIR_BYTE2_ADDRESS         ((uint32_t)(RCC_BASE + 0x0C + 0x01))
+
+/* CIR register byte 3 (Bits[23:16]) base address */
+#define CIR_BYTE3_ADDRESS         ((uint32_t)(RCC_BASE + 0x0C + 0x02))
+
+/* BDCR register base address */
+#define BDCR_ADDRESS              (PERIPH_BASE + BDCR_OFFSET)
+
+/* Private macro -------------------------------------------------------------*/
+/* Private variables ---------------------------------------------------------*/
+static __I uint8_t APBAHBPrescTable[16] = {0, 0, 0, 0, 1, 2, 3, 4, 1, 2, 3, 4, 6, 7, 8, 9};
+
+/* Private function prototypes -----------------------------------------------*/
+/* Private functions ---------------------------------------------------------*/
+
+/** @defgroup RCC_Private_Functions
+  * @{
+  */ 
+
+/** @defgroup RCC_Group1 Internal and external clocks, PLL, CSS and MCO configuration functions
+ *  @brief   Internal and external clocks, PLL, CSS and MCO configuration functions 
+ *
+@verbatim   
+ ===============================================================================
+      Internal/external clocks, PLL, CSS and MCO configuration functions
+ ===============================================================================  
+
+  This section provide functions allowing to configure the internal/external clocks,
+  PLLs, CSS and MCO pins.
+  
+  1. HSI (high-speed internal), 16 MHz factory-trimmed RC used directly or through
+     the PLL as System clock source.
+
+  2. LSI (low-speed internal), 32 KHz low consumption RC used as IWDG and/or RTC
+     clock source.
+
+  3. HSE (high-speed external), 4 to 26 MHz crystal oscillator used directly or
+     through the PLL as System clock source. Can be used also as RTC clock source.
+
+  4. LSE (low-speed external), 32 KHz oscillator used as RTC clock source.   
+
+  5. PLL (clocked by HSI or HSE), featuring two different output clocks:
+      - The first output is used to generate the high speed system clock (up to 168 MHz)
+      - The second output is used to generate the clock for the USB OTG FS (48 MHz),
+        the random analog generator (<=48 MHz) and the SDIO (<= 48 MHz).
+
+  6. PLLI2S (clocked by HSI or HSE), used to generate an accurate clock to achieve 
+     high-quality audio performance on the I2S interface.
+  
+  7. CSS (Clock security system), once enable and if a HSE clock failure occurs 
+     (HSE used directly or through PLL as System clock source), the System clock
+     is automatically switched to HSI and an interrupt is generated if enabled. 
+     The interrupt is linked to the Cortex-M4 NMI (Non-Maskable Interrupt) 
+     exception vector.   
+
+  8. MCO1 (microcontroller clock output), used to output HSI, LSE, HSE or PLL
+     clock (through a configurable prescaler) on PA8 pin.
+
+  9. MCO2 (microcontroller clock output), used to output HSE, PLL, SYSCLK or PLLI2S
+     clock (through a configurable prescaler) on PC9 pin.
+
+@endverbatim
+  * @{
+  */
+
+/**
+  * @brief  Resets the RCC clock configuration to the default reset state.
+  * @note   The default reset state of the clock configuration is given below:
+  *            - HSI ON and used as system clock source
+  *            - HSE, PLL and PLLI2S OFF
+  *            - AHB, APB1 and APB2 prescaler set to 1.
+  *            - CSS, MCO1 and MCO2 OFF
+  *            - All interrupts disabled
+  * @note   This function doesn't modify the configuration of the
+  *            - Peripheral clocks
+  *            - LSI, LSE and RTC clocks 
+  * @param  None
+  * @retval None
+  */
+void RCC_DeInit(void)
+{
+  /* Set HSION bit */
+  RCC->CR |= (uint32_t)0x00000001;
+
+  /* Reset CFGR register */
+  RCC->CFGR = 0x00000000;
+
+  /* Reset HSEON, CSSON and PLLON bits */
+  RCC->CR &= (uint32_t)0xFEF6FFFF;
+
+  /* Reset PLLCFGR register */
+  RCC->PLLCFGR = 0x24003010;
+
+  /* Reset HSEBYP bit */
+  RCC->CR &= (uint32_t)0xFFFBFFFF;
+
+  /* Disable all interrupts */
+  RCC->CIR = 0x00000000;
+}
+
+/**
+  * @brief  Configures the External High Speed oscillator (HSE).
+  * @note   After enabling the HSE (RCC_HSE_ON or RCC_HSE_Bypass), the application
+  *         software should wait on HSERDY flag to be set indicating that HSE clock
+  *         is stable and can be used to clock the PLL and/or system clock.
+  * @note   HSE state can not be changed if it is used directly or through the
+  *         PLL as system clock. In this case, you have to select another source
+  *         of the system clock then change the HSE state (ex. disable it).
+  * @note   The HSE is stopped by hardware when entering STOP and STANDBY modes.  
+  * @note   This function reset the CSSON bit, so if the Clock security system(CSS)
+  *         was previously enabled you have to enable it again after calling this
+  *         function.    
+  * @param  RCC_HSE: specifies the new state of the HSE.
+  *          This parameter can be one of the following values:
+  *            @arg RCC_HSE_OFF: turn OFF the HSE oscillator, HSERDY flag goes low after
+  *                              6 HSE oscillator clock cycles.
+  *            @arg RCC_HSE_ON: turn ON the HSE oscillator
+  *            @arg RCC_HSE_Bypass: HSE oscillator bypassed with external clock
+  * @retval None
+  */
+void RCC_HSEConfig(uint8_t RCC_HSE)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_HSE(RCC_HSE));
+
+  /* Reset HSEON and HSEBYP bits before configuring the HSE ------------------*/
+  *(__IO uint8_t *) CR_BYTE3_ADDRESS = RCC_HSE_OFF;
+
+  /* Set the new HSE configuration -------------------------------------------*/
+  *(__IO uint8_t *) CR_BYTE3_ADDRESS = RCC_HSE;
+}
+
+/**
+  * @brief  Waits for HSE start-up.
+  * @note   This functions waits on HSERDY flag to be set and return SUCCESS if 
+  *         this flag is set, otherwise returns ERROR if the timeout is reached 
+  *         and this flag is not set. The timeout value is defined by the constant
+  *         HSE_STARTUP_TIMEOUT in stm32f4xx.h file. You can tailor it depending
+  *         on the HSE crystal used in your application. 
+  * @param  None
+  * @retval An ErrorStatus enumeration value:
+  *          - SUCCESS: HSE oscillator is stable and ready to use
+  *          - ERROR: HSE oscillator not yet ready
+  */
+ErrorStatus RCC_WaitForHSEStartUp(void)
+{
+  __IO uint32_t startupcounter = 0;
+  ErrorStatus status = ERROR;
+  FlagStatus hsestatus = RESET;
+  /* Wait till HSE is ready and if Time out is reached exit */
+  do
+  {
+    hsestatus = RCC_GetFlagStatus(RCC_FLAG_HSERDY);
+    startupcounter++;
+  } while((startupcounter != HSE_STARTUP_TIMEOUT) && (hsestatus == RESET));
+
+  if (RCC_GetFlagStatus(RCC_FLAG_HSERDY) != RESET)
+  {
+    status = SUCCESS;
+  }
+  else
+  {
+    status = ERROR;
+  }
+  return (status);
+}
+
+/**
+  * @brief  Adjusts the Internal High Speed oscillator (HSI) calibration value.
+  * @note   The calibration is used to compensate for the variations in voltage
+  *         and temperature that influence the frequency of the internal HSI RC.
+  * @param  HSICalibrationValue: specifies the calibration trimming value.
+  *         This parameter must be a number between 0 and 0x1F.
+  * @retval None
+  */
+void RCC_AdjustHSICalibrationValue(uint8_t HSICalibrationValue)
+{
+  uint32_t tmpreg = 0;
+  /* Check the parameters */
+  assert_param(IS_RCC_CALIBRATION_VALUE(HSICalibrationValue));
+
+  tmpreg = RCC->CR;
+
+  /* Clear HSITRIM[4:0] bits */
+  tmpreg &= ~RCC_CR_HSITRIM;
+
+  /* Set the HSITRIM[4:0] bits according to HSICalibrationValue value */
+  tmpreg |= (uint32_t)HSICalibrationValue << 3;
+
+  /* Store the new value */
+  RCC->CR = tmpreg;
+}
+
+/**
+  * @brief  Enables or disables the Internal High Speed oscillator (HSI).
+  * @note   The HSI is stopped by hardware when entering STOP and STANDBY modes.
+  *         It is used (enabled by hardware) as system clock source after startup
+  *         from Reset, wakeup from STOP and STANDBY mode, or in case of failure
+  *         of the HSE used directly or indirectly as system clock (if the Clock
+  *         Security System CSS is enabled).             
+  * @note   HSI can not be stopped if it is used as system clock source. In this case,
+  *         you have to select another source of the system clock then stop the HSI.  
+  * @note   After enabling the HSI, the application software should wait on HSIRDY
+  *         flag to be set indicating that HSI clock is stable and can be used as
+  *         system clock source.  
+  * @param  NewState: new state of the HSI.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @note   When the HSI is stopped, HSIRDY flag goes low after 6 HSI oscillator
+  *         clock cycles.  
+  * @retval None
+  */
+void RCC_HSICmd(FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+  *(__IO uint32_t *) CR_HSION_BB = (uint32_t)NewState;
+}
+
+/**
+  * @brief  Configures the External Low Speed oscillator (LSE).
+  * @note   As the LSE is in the Backup domain and write access is denied to
+  *         this domain after reset, you have to enable write access using 
+  *         PWR_BackupAccessCmd(ENABLE) function before to configure the LSE
+  *         (to be done once after reset).  
+  * @note   After enabling the LSE (RCC_LSE_ON or RCC_LSE_Bypass), the application
+  *         software should wait on LSERDY flag to be set indicating that LSE clock
+  *         is stable and can be used to clock the RTC.
+  * @param  RCC_LSE: specifies the new state of the LSE.
+  *          This parameter can be one of the following values:
+  *            @arg RCC_LSE_OFF: turn OFF the LSE oscillator, LSERDY flag goes low after
+  *                              6 LSE oscillator clock cycles.
+  *            @arg RCC_LSE_ON: turn ON the LSE oscillator
+  *            @arg RCC_LSE_Bypass: LSE oscillator bypassed with external clock
+  * @retval None
+  */
+void RCC_LSEConfig(uint8_t RCC_LSE)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_LSE(RCC_LSE));
+
+  /* Reset LSEON and LSEBYP bits before configuring the LSE ------------------*/
+  /* Reset LSEON bit */
+  *(__IO uint8_t *) BDCR_ADDRESS = RCC_LSE_OFF;
+
+  /* Reset LSEBYP bit */
+  *(__IO uint8_t *) BDCR_ADDRESS = 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 */
+      *(__IO uint8_t *) BDCR_ADDRESS = RCC_LSE_ON;
+      break;
+    case RCC_LSE_Bypass:
+      /* Set LSEBYP and LSEON bits */
+      *(__IO uint8_t *) BDCR_ADDRESS = RCC_LSE_Bypass | RCC_LSE_ON;
+      break;
+    default:
+      break;
+  }
+}
+
+/**
+  * @brief  Enables or disables the Internal Low Speed oscillator (LSI).
+  * @note   After enabling the LSI, the application software should wait on 
+  *         LSIRDY flag to be set indicating that LSI clock is stable and can
+  *         be used to clock the IWDG and/or the RTC.
+  * @note   LSI can not be disabled if the IWDG is running.  
+  * @param  NewState: new state of the LSI.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @note   When the LSI is stopped, LSIRDY flag goes low after 6 LSI oscillator
+  *         clock cycles. 
+  * @retval None
+  */
+void RCC_LSICmd(FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+  *(__IO uint32_t *) CSR_LSION_BB = (uint32_t)NewState;
+}
+
+/**
+  * @brief  Configures the main PLL clock source, multiplication and division factors.
+  * @note   This function must be used only when the main PLL is disabled.
+  *  
+  * @param  RCC_PLLSource: specifies the PLL entry clock source.
+  *          This parameter can be one of the following values:
+  *            @arg RCC_PLLSource_HSI: HSI oscillator clock selected as PLL clock entry
+  *            @arg RCC_PLLSource_HSE: HSE oscillator clock selected as PLL clock entry
+  * @note   This clock source (RCC_PLLSource) is common for the main PLL and PLLI2S.  
+  *  
+  * @param  PLLM: specifies the division factor for PLL VCO input clock
+  *          This parameter must be a number between 0 and 63.
+  * @note   You have to set the PLLM parameter correctly to ensure that the VCO input
+  *         frequency ranges from 1 to 2 MHz. It is recommended to select a frequency
+  *         of 2 MHz to limit PLL jitter.
+  *  
+  * @param  PLLN: specifies the multiplication factor for PLL VCO output clock
+  *          This parameter must be a number between 192 and 432.
+  * @note   You have to set the PLLN parameter correctly to ensure that the VCO
+  *         output frequency is between 192 and 432 MHz.
+  *   
+  * @param  PLLP: specifies the division factor for main system clock (SYSCLK)
+  *          This parameter must be a number in the range {2, 4, 6, or 8}.
+  * @note   You have to set the PLLP parameter correctly to not exceed 168 MHz on
+  *         the System clock frequency.
+  *  
+  * @param  PLLQ: specifies the division factor for OTG FS, SDIO and RNG clocks
+  *          This parameter must be a number between 4 and 15.
+  * @note   If the USB OTG FS is used in your application, you have to set the
+  *         PLLQ parameter correctly to have 48 MHz clock for the USB. However,
+  *         the SDIO and RNG need a frequency lower than or equal to 48 MHz to work
+  *         correctly.
+  *   
+  * @retval None
+  */
+void RCC_PLLConfig(uint32_t RCC_PLLSource, uint32_t PLLM, uint32_t PLLN, uint32_t PLLP, uint32_t PLLQ)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_PLL_SOURCE(RCC_PLLSource));
+  assert_param(IS_RCC_PLLM_VALUE(PLLM));
+  assert_param(IS_RCC_PLLN_VALUE(PLLN));
+  assert_param(IS_RCC_PLLP_VALUE(PLLP));
+  assert_param(IS_RCC_PLLQ_VALUE(PLLQ));
+
+  RCC->PLLCFGR = PLLM | (PLLN << 6) | (((PLLP >> 1) -1) << 16) | (RCC_PLLSource) |
+                 (PLLQ << 24);
+}
+
+/**
+  * @brief  Enables or disables the main PLL.
+  * @note   After enabling the main PLL, the application software should wait on 
+  *         PLLRDY flag to be set indicating that PLL clock is stable and can
+  *         be used as system clock source.
+  * @note   The main PLL can not be disabled if it is used as system clock source
+  * @note   The main PLL is disabled by hardware when entering STOP and STANDBY modes.
+  * @param  NewState: new state of the main PLL. This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_PLLCmd(FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+  *(__IO uint32_t *) CR_PLLON_BB = (uint32_t)NewState;
+}
+
+/**
+  * @brief  Configures the PLLI2S clock multiplication and division factors.
+  *  
+  * @note   This function must be used only when the PLLI2S is disabled.
+  * @note   PLLI2S clock source is common with the main PLL (configured in 
+  *         RCC_PLLConfig function )  
+  *             
+  * @param  PLLI2SN: specifies the multiplication factor for PLLI2S VCO output clock
+  *          This parameter must be a number between 192 and 432.
+  * @note   You have to set the PLLI2SN parameter correctly to ensure that the VCO 
+  *         output frequency is between 192 and 432 MHz.
+  *    
+  * @param  PLLI2SR: specifies the division factor for I2S clock
+  *          This parameter must be a number between 2 and 7.
+  * @note   You have to set the PLLI2SR parameter correctly to not exceed 192 MHz
+  *         on the I2S clock frequency.
+  *   
+  * @retval None
+  */
+void RCC_PLLI2SConfig(uint32_t PLLI2SN, uint32_t PLLI2SR)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_PLLI2SN_VALUE(PLLI2SN));
+  assert_param(IS_RCC_PLLI2SR_VALUE(PLLI2SR));
+
+  RCC->PLLI2SCFGR = (PLLI2SN << 6) | (PLLI2SR << 28);
+}
+
+/**
+  * @brief  Enables or disables the PLLI2S. 
+  * @note   The PLLI2S is disabled by hardware when entering STOP and STANDBY modes.  
+  * @param  NewState: new state of the PLLI2S. This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_PLLI2SCmd(FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+  *(__IO uint32_t *) CR_PLLI2SON_BB = (uint32_t)NewState;
+}
+
+/**
+  * @brief  Enables or disables the Clock Security System.
+  * @note   If a failure is detected on the HSE oscillator clock, this oscillator
+  *         is automatically disabled and an interrupt is generated to inform the
+  *         software about the failure (Clock Security System Interrupt, CSSI),
+  *         allowing the MCU to perform rescue operations. The CSSI is linked to 
+  *         the Cortex-M4 NMI (Non-Maskable Interrupt) exception vector.  
+  * @param  NewState: new state of the Clock Security System.
+  *         This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_ClockSecuritySystemCmd(FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+  *(__IO uint32_t *) CR_CSSON_BB = (uint32_t)NewState;
+}
+
+/**
+  * @brief  Selects the clock source to output on MCO1 pin(PA8).
+  * @note   PA8 should be configured in alternate function mode.
+  * @param  RCC_MCO1Source: specifies the clock source to output.
+  *          This parameter can be one of the following values:
+  *            @arg RCC_MCO1Source_HSI: HSI clock selected as MCO1 source
+  *            @arg RCC_MCO1Source_LSE: LSE clock selected as MCO1 source
+  *            @arg RCC_MCO1Source_HSE: HSE clock selected as MCO1 source
+  *            @arg RCC_MCO1Source_PLLCLK: main PLL clock selected as MCO1 source
+  * @param  RCC_MCO1Div: specifies the MCO1 prescaler.
+  *          This parameter can be one of the following values:
+  *            @arg RCC_MCO1Div_1: no division applied to MCO1 clock
+  *            @arg RCC_MCO1Div_2: division by 2 applied to MCO1 clock
+  *            @arg RCC_MCO1Div_3: division by 3 applied to MCO1 clock
+  *            @arg RCC_MCO1Div_4: division by 4 applied to MCO1 clock
+  *            @arg RCC_MCO1Div_5: division by 5 applied to MCO1 clock
+  * @retval None
+  */
+void RCC_MCO1Config(uint32_t RCC_MCO1Source, uint32_t RCC_MCO1Div)
+{
+  uint32_t tmpreg = 0;
+  
+  /* Check the parameters */
+  assert_param(IS_RCC_MCO1SOURCE(RCC_MCO1Source));
+  assert_param(IS_RCC_MCO1DIV(RCC_MCO1Div));  
+
+  tmpreg = RCC->CFGR;
+
+  /* Clear MCO1[1:0] and MCO1PRE[2:0] bits */
+  tmpreg &= CFGR_MCO1_RESET_MASK;
+
+  /* Select MCO1 clock source and prescaler */
+  tmpreg |= RCC_MCO1Source | RCC_MCO1Div;
+
+  /* Store the new value */
+  RCC->CFGR = tmpreg;  
+}
+
+/**
+  * @brief  Selects the clock source to output on MCO2 pin(PC9).
+  * @note   PC9 should be configured in alternate function mode.
+  * @param  RCC_MCO2Source: specifies the clock source to output.
+  *          This parameter can be one of the following values:
+  *            @arg RCC_MCO2Source_SYSCLK: System clock (SYSCLK) selected as MCO2 source
+  *            @arg RCC_MCO2Source_PLLI2SCLK: PLLI2S clock selected as MCO2 source
+  *            @arg RCC_MCO2Source_HSE: HSE clock selected as MCO2 source
+  *            @arg RCC_MCO2Source_PLLCLK: main PLL clock selected as MCO2 source
+  * @param  RCC_MCO2Div: specifies the MCO2 prescaler.
+  *          This parameter can be one of the following values:
+  *            @arg RCC_MCO2Div_1: no division applied to MCO2 clock
+  *            @arg RCC_MCO2Div_2: division by 2 applied to MCO2 clock
+  *            @arg RCC_MCO2Div_3: division by 3 applied to MCO2 clock
+  *            @arg RCC_MCO2Div_4: division by 4 applied to MCO2 clock
+  *            @arg RCC_MCO2Div_5: division by 5 applied to MCO2 clock
+  * @retval None
+  */
+void RCC_MCO2Config(uint32_t RCC_MCO2Source, uint32_t RCC_MCO2Div)
+{
+  uint32_t tmpreg = 0;
+  
+  /* Check the parameters */
+  assert_param(IS_RCC_MCO2SOURCE(RCC_MCO2Source));
+  assert_param(IS_RCC_MCO2DIV(RCC_MCO2Div));
+  
+  tmpreg = RCC->CFGR;
+  
+  /* Clear MCO2 and MCO2PRE[2:0] bits */
+  tmpreg &= CFGR_MCO2_RESET_MASK;
+
+  /* Select MCO2 clock source and prescaler */
+  tmpreg |= RCC_MCO2Source | RCC_MCO2Div;
+
+  /* Store the new value */
+  RCC->CFGR = tmpreg;  
+}
+
+/**
+  * @}
+  */
+
+/** @defgroup RCC_Group2 System AHB and APB busses clocks configuration functions
+ *  @brief   System, AHB and APB busses clocks configuration functions
+ *
+@verbatim   
+ ===============================================================================
+             System, AHB and APB busses clocks configuration functions
+ ===============================================================================  
+
+  This section provide functions allowing to configure the System, AHB, APB1 and 
+  APB2 busses clocks.
+  
+  1. Several clock sources can be used to drive the System clock (SYSCLK): HSI,
+     HSE and PLL.
+     The AHB clock (HCLK) is derived from System clock through configurable prescaler
+     and used to clock the CPU, memory and peripherals mapped on AHB bus (DMA, GPIO...).
+     APB1 (PCLK1) and APB2 (PCLK2) clocks are derived from AHB clock through 
+     configurable prescalers and used to clock the peripherals mapped on these busses.
+     You can use "RCC_GetClocksFreq()" function to retrieve the frequencies of these clocks.  
+
+@note All the peripheral clocks are derived from the System clock (SYSCLK) except:
+       - I2S: the I2S clock can be derived either from a specific PLL (PLLI2S) or
+          from an external clock mapped on the I2S_CKIN pin. 
+          You have to use RCC_I2SCLKConfig() function to configure this clock. 
+       - RTC: the RTC clock can be derived either from the LSI, LSE or HSE clock
+          divided by 2 to 31. You have to use RCC_RTCCLKConfig() and RCC_RTCCLKCmd()
+          functions to configure this clock. 
+       - USB OTG FS, SDIO and RTC: USB OTG FS require a frequency equal to 48 MHz
+          to work correctly, while the SDIO require a frequency equal or lower than
+          to 48. This clock is derived of the main PLL through PLLQ divider.
+       - IWDG clock which is always the LSI clock.
+       
+  2. The maximum frequency of the SYSCLK and HCLK is 168 MHz, PCLK2 82 MHz and PCLK1 42 MHz.
+     Depending on the device voltage range, the maximum frequency should be 
+     adapted accordingly:
+ +-------------------------------------------------------------------------------------+     
+ | Latency       |                HCLK clock frequency (MHz)                           |
+ |               |---------------------------------------------------------------------|     
+ |               | voltage range  | voltage range  | voltage range   | voltage range   |
+ |               | 2.7 V - 3.6 V  | 2.4 V - 2.7 V  | 2.1 V - 2.4 V   | 1.8 V - 2.1 V   |
+ |---------------|----------------|----------------|-----------------|-----------------|              
+ |0WS(1CPU cycle)|0 < HCLK <= 30  |0 < HCLK <= 24  |0 < HCLK <= 18   |0 < HCLK <= 16   |
+ |---------------|----------------|----------------|-----------------|-----------------|   
+ |1WS(2CPU cycle)|30 < HCLK <= 60 |24 < HCLK <= 48 |18 < HCLK <= 36  |16 < HCLK <= 32  | 
+ |---------------|----------------|----------------|-----------------|-----------------|   
+ |2WS(3CPU cycle)|60 < HCLK <= 90 |48 < HCLK <= 72 |36 < HCLK <= 54  |32 < HCLK <= 48  |
+ |---------------|----------------|----------------|-----------------|-----------------| 
+ |3WS(4CPU cycle)|90 < HCLK <= 120|72 < HCLK <= 96 |54 < HCLK <= 72  |48 < HCLK <= 64  |
+ |---------------|----------------|----------------|-----------------|-----------------| 
+ |4WS(5CPU cycle)|120< HCLK <= 150|96 < HCLK <= 120|72 < HCLK <= 90  |64 < HCLK <= 80  |
+ |---------------|----------------|----------------|-----------------|-----------------| 
+ |5WS(6CPU cycle)|120< HCLK <= 168|120< HCLK <= 144|90 < HCLK <= 108 |80 < HCLK <= 96  | 
+ |---------------|----------------|----------------|-----------------|-----------------| 
+ |6WS(7CPU cycle)|      NA        |144< HCLK <= 168|108 < HCLK <= 120|96 < HCLK <= 112 | 
+ |---------------|----------------|----------------|-----------------|-----------------| 
+ |7WS(8CPU cycle)|      NA        |      NA        |120 < HCLK <= 138|112 < HCLK <= 120| 
+ +-------------------------------------------------------------------------------------+    
+   @note When VOS bit (in PWR_CR register) is reset to '0’, the maximum value of HCLK is 144 MHz.
+         You can use PWR_MainRegulatorModeConfig() function to set or reset this bit.
+
+@endverbatim
+  * @{
+  */
+
+/**
+  * @brief  Configures the system clock (SYSCLK).
+  * @note   The HSI is used (enabled by hardware) as system clock source after
+  *         startup from Reset, wake-up from STOP and STANDBY mode, or in case
+  *         of failure of the HSE used directly or indirectly as system clock
+  *         (if the Clock Security System CSS is enabled).
+  * @note   A switch from one clock source to another occurs only if the target
+  *         clock source is ready (clock stable after startup delay or PLL locked). 
+  *         If a clock source which is not yet ready is selected, the switch will
+  *         occur when the clock source will be ready. 
+  *         You can use RCC_GetSYSCLKSource() function to know which clock is
+  *         currently used as system clock source. 
+  * @param  RCC_SYSCLKSource: specifies the clock source used as system clock.
+  *          This parameter can be one of the following values:
+  *            @arg RCC_SYSCLKSource_HSI:    HSI selected as system clock source
+  *            @arg RCC_SYSCLKSource_HSE:    HSE selected as system clock source
+  *            @arg RCC_SYSCLKSource_PLLCLK: PLL selected as system clock source
+  * @retval None
+  */
+void RCC_SYSCLKConfig(uint32_t RCC_SYSCLKSource)
+{
+  uint32_t tmpreg = 0;
+
+  /* Check the parameters */
+  assert_param(IS_RCC_SYSCLK_SOURCE(RCC_SYSCLKSource));
+
+  tmpreg = RCC->CFGR;
+
+  /* Clear SW[1:0] bits */
+  tmpreg &= ~RCC_CFGR_SW;
+
+  /* Set SW[1:0] bits according to RCC_SYSCLKSource value */
+  tmpreg |= RCC_SYSCLKSource;
+
+  /* Store the new value */
+  RCC->CFGR = tmpreg;
+}
+
+/**
+  * @brief  Returns the clock source used as system clock.
+  * @param  None
+  * @retval 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
+  */
+uint8_t RCC_GetSYSCLKSource(void)
+{
+  return ((uint8_t)(RCC->CFGR & RCC_CFGR_SWS));
+}
+
+/**
+  * @brief  Configures the AHB clock (HCLK).
+  * @note   Depending on the device voltage range, the software has to set correctly
+  *         these bits to ensure that HCLK not exceed the maximum allowed frequency
+  *         (for more details refer to section above
+  *           "CPU, AHB and APB busses clocks configuration functions")
+  * @param  RCC_SYSCLK: defines the AHB clock divider. This clock is derived from 
+  *         the system clock (SYSCLK).
+  *          This parameter can be one of the following values:
+  *            @arg RCC_SYSCLK_Div1: AHB clock = SYSCLK
+  *            @arg RCC_SYSCLK_Div2: AHB clock = SYSCLK/2
+  *            @arg RCC_SYSCLK_Div4: AHB clock = SYSCLK/4
+  *            @arg RCC_SYSCLK_Div8: AHB clock = SYSCLK/8
+  *            @arg RCC_SYSCLK_Div16: AHB clock = SYSCLK/16
+  *            @arg RCC_SYSCLK_Div64: AHB clock = SYSCLK/64
+  *            @arg RCC_SYSCLK_Div128: AHB clock = SYSCLK/128
+  *            @arg RCC_SYSCLK_Div256: AHB clock = SYSCLK/256
+  *            @arg RCC_SYSCLK_Div512: AHB clock = SYSCLK/512
+  * @retval None
+  */
+void RCC_HCLKConfig(uint32_t RCC_SYSCLK)
+{
+  uint32_t tmpreg = 0;
+  
+  /* Check the parameters */
+  assert_param(IS_RCC_HCLK(RCC_SYSCLK));
+
+  tmpreg = RCC->CFGR;
+
+  /* Clear HPRE[3:0] bits */
+  tmpreg &= ~RCC_CFGR_HPRE;
+
+  /* Set HPRE[3:0] bits according to RCC_SYSCLK value */
+  tmpreg |= RCC_SYSCLK;
+
+  /* Store the new value */
+  RCC->CFGR = tmpreg;
+}
+
+
+/**
+  * @brief  Configures the Low Speed APB clock (PCLK1).
+  * @param  RCC_HCLK: defines the APB1 clock divider. This clock is derived from 
+  *         the AHB clock (HCLK).
+  *          This parameter can be one of the following values:
+  *            @arg RCC_HCLK_Div1:  APB1 clock = HCLK
+  *            @arg RCC_HCLK_Div2:  APB1 clock = HCLK/2
+  *            @arg RCC_HCLK_Div4:  APB1 clock = HCLK/4
+  *            @arg RCC_HCLK_Div8:  APB1 clock = HCLK/8
+  *            @arg RCC_HCLK_Div16: APB1 clock = HCLK/16
+  * @retval None
+  */
+void RCC_PCLK1Config(uint32_t RCC_HCLK)
+{
+  uint32_t tmpreg = 0;
+
+  /* Check the parameters */
+  assert_param(IS_RCC_PCLK(RCC_HCLK));
+
+  tmpreg = RCC->CFGR;
+
+  /* Clear PPRE1[2:0] bits */
+  tmpreg &= ~RCC_CFGR_PPRE1;
+
+  /* Set PPRE1[2:0] bits according to RCC_HCLK value */
+  tmpreg |= RCC_HCLK;
+
+  /* Store the new value */
+  RCC->CFGR = tmpreg;
+}
+
+/**
+  * @brief  Configures the High Speed APB clock (PCLK2).
+  * @param  RCC_HCLK: defines the APB2 clock divider. This clock is derived from 
+  *         the AHB clock (HCLK).
+  *          This parameter can be one of the following values:
+  *            @arg RCC_HCLK_Div1:  APB2 clock = HCLK
+  *            @arg RCC_HCLK_Div2:  APB2 clock = HCLK/2
+  *            @arg RCC_HCLK_Div4:  APB2 clock = HCLK/4
+  *            @arg RCC_HCLK_Div8:  APB2 clock = HCLK/8
+  *            @arg RCC_HCLK_Div16: APB2 clock = HCLK/16
+  * @retval None
+  */
+void RCC_PCLK2Config(uint32_t RCC_HCLK)
+{
+  uint32_t tmpreg = 0;
+
+  /* Check the parameters */
+  assert_param(IS_RCC_PCLK(RCC_HCLK));
+
+  tmpreg = RCC->CFGR;
+
+  /* Clear PPRE2[2:0] bits */
+  tmpreg &= ~RCC_CFGR_PPRE2;
+
+  /* Set PPRE2[2:0] bits according to RCC_HCLK value */
+  tmpreg |= RCC_HCLK << 3;
+
+  /* Store the new value */
+  RCC->CFGR = tmpreg;
+}
+
+/**
+  * @brief  Returns the frequencies of different on chip clocks; SYSCLK, HCLK, 
+  *         PCLK1 and PCLK2.       
+  * 
+  * @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:
+  * @note     If SYSCLK source is HSI, function returns values based on HSI_VALUE(*)
+  * @note     If SYSCLK source is HSE, function returns values based on HSE_VALUE(**)
+  * @note     If SYSCLK source is PLL, function returns values based on HSE_VALUE(**) 
+  *           or HSI_VALUE(*) multiplied/divided by the PLL factors.         
+  * @note     (*) HSI_VALUE is a constant defined in stm32f4xx.h file (default value
+  *               16 MHz) but the real value may vary depending on the variations
+  *               in voltage and temperature.
+  * @note     (**) HSE_VALUE is a constant defined in stm32f4xx.h file (default value
+  *                25 MHz), user has to ensure that HSE_VALUE is same as the real
+  *                frequency of the crystal used. Otherwise, this function may
+  *                have wrong result.
+  *                
+  * @note   The result of this function could be not correct when using fractional
+  *         value for HSE crystal.
+  *   
+  * @param  RCC_Clocks: pointer to a RCC_ClocksTypeDef structure which will hold
+  *          the clocks frequencies.
+  *     
+  * @note   This function can be used by the user application to compute the 
+  *         baudrate for the communication peripherals or configure other parameters.
+  * @note   Each time SYSCLK, HCLK, PCLK1 and/or PCLK2 clock changes, this function
+  *         must be called to update the structure's field. Otherwise, any
+  *         configuration based on this function will be incorrect.
+  *    
+  * @retval None
+  */
+void RCC_GetClocksFreq(RCC_ClocksTypeDef* RCC_Clocks)
+{
+  uint32_t tmp = 0, presc = 0, pllvco = 0, pllp = 2, pllsource = 0, pllm = 2;
+
+  /* Get SYSCLK source -------------------------------------------------------*/
+  tmp = RCC->CFGR & RCC_CFGR_SWS;
+
+  switch (tmp)
+  {
+    case 0x00:  /* HSI used as system clock source */
+      RCC_Clocks->SYSCLK_Frequency = HSI_VALUE;
+      break;
+    case 0x04:  /* HSE used as system clock  source */
+      RCC_Clocks->SYSCLK_Frequency = HSE_VALUE;
+      break;
+    case 0x08:  /* PLL used as system clock  source */
+
+      /* PLL_VCO = (HSE_VALUE or HSI_VALUE / PLLM) * PLLN
+         SYSCLK = PLL_VCO / PLLP
+         */    
+      pllsource = (RCC->PLLCFGR & RCC_PLLCFGR_PLLSRC) >> 22;
+      pllm = RCC->PLLCFGR & RCC_PLLCFGR_PLLM;
+      
+      if (pllsource != 0)
+      {
+        /* HSE used as PLL clock source */
+        pllvco = (HSE_VALUE / pllm) * ((RCC->PLLCFGR & RCC_PLLCFGR_PLLN) >> 6);
+      }
+      else
+      {
+        /* HSI used as PLL clock source */
+        pllvco = (HSI_VALUE / pllm) * ((RCC->PLLCFGR & RCC_PLLCFGR_PLLN) >> 6);      
+      }
+
+      pllp = (((RCC->PLLCFGR & RCC_PLLCFGR_PLLP) >>16) + 1 ) *2;
+      RCC_Clocks->SYSCLK_Frequency = pllvco/pllp;
+      break;
+    default:
+      RCC_Clocks->SYSCLK_Frequency = HSI_VALUE;
+      break;
+  }
+  /* Compute HCLK, PCLK1 and PCLK2 clocks frequencies ------------------------*/
+
+  /* Get HCLK prescaler */
+  tmp = RCC->CFGR & RCC_CFGR_HPRE;
+  tmp = tmp >> 4;
+  presc = APBAHBPrescTable[tmp];
+  /* HCLK clock frequency */
+  RCC_Clocks->HCLK_Frequency = RCC_Clocks->SYSCLK_Frequency >> presc;
+
+  /* Get PCLK1 prescaler */
+  tmp = RCC->CFGR & RCC_CFGR_PPRE1;
+  tmp = tmp >> 10;
+  presc = APBAHBPrescTable[tmp];
+  /* PCLK1 clock frequency */
+  RCC_Clocks->PCLK1_Frequency = RCC_Clocks->HCLK_Frequency >> presc;
+
+  /* Get PCLK2 prescaler */
+  tmp = RCC->CFGR & RCC_CFGR_PPRE2;
+  tmp = tmp >> 13;
+  presc = APBAHBPrescTable[tmp];
+  /* PCLK2 clock frequency */
+  RCC_Clocks->PCLK2_Frequency = RCC_Clocks->HCLK_Frequency >> presc;
+}
+
+/**
+  * @}
+  */
+
+/** @defgroup RCC_Group3 Peripheral clocks configuration functions
+ *  @brief   Peripheral clocks configuration functions 
+ *
+@verbatim   
+ ===============================================================================
+                   Peripheral clocks configuration functions
+ ===============================================================================  
+
+  This section provide functions allowing to configure the Peripheral clocks. 
+  
+  1. The RTC clock which is derived from the LSI, LSE or HSE clock divided by 2 to 31.
+     
+  2. After restart from Reset or wakeup from STANDBY, all peripherals are off
+     except internal SRAM, Flash and JTAG. Before to start using a peripheral you
+     have to enable its interface clock. You can do this using RCC_AHBPeriphClockCmd()
+     , RCC_APB2PeriphClockCmd() and RCC_APB1PeriphClockCmd() functions.
+
+  3. To reset the peripherals configuration (to the default state after device reset)
+     you can use RCC_AHBPeriphResetCmd(), RCC_APB2PeriphResetCmd() and 
+     RCC_APB1PeriphResetCmd() functions.
+     
+  4. To further reduce power consumption in SLEEP mode the peripheral clocks can
+     be disabled prior to executing the WFI or WFE instructions. You can do this
+     using RCC_AHBPeriphClockLPModeCmd(), RCC_APB2PeriphClockLPModeCmd() and
+     RCC_APB1PeriphClockLPModeCmd() functions.  
+
+@endverbatim
+  * @{
+  */
+
+/**
+  * @brief  Configures the RTC clock (RTCCLK).
+  * @note   As the RTC clock configuration bits are in the Backup domain and write
+  *         access is denied to this domain after reset, you have to enable write
+  *         access using PWR_BackupAccessCmd(ENABLE) function before to configure
+  *         the RTC clock source (to be done once after reset).    
+  * @note   Once the RTC clock is configured it can't be changed unless the  
+  *         Backup domain is reset using RCC_BackupResetCmd() function, or by
+  *         a Power On Reset (POR).
+  *    
+  * @param  RCC_RTCCLKSource: specifies the RTC clock source.
+  *          This parameter can be one of the following values:
+  *            @arg RCC_RTCCLKSource_LSE: LSE selected as RTC clock
+  *            @arg RCC_RTCCLKSource_LSI: LSI selected as RTC clock
+  *            @arg RCC_RTCCLKSource_HSE_Divx: HSE clock divided by x selected
+  *                                            as RTC clock, where x:[2,31]
+  *  
+  * @note   If the LSE or LSI is used as RTC clock source, the RTC continues to
+  *         work in STOP and STANDBY modes, and can be used as wakeup source.
+  *         However, when the HSE clock is used as RTC clock source, the RTC
+  *         cannot be used in STOP and STANDBY modes.    
+  * @note   The maximum input clock frequency for RTC is 1MHz (when using HSE as
+  *         RTC clock source).
+  *  
+  * @retval None
+  */
+void RCC_RTCCLKConfig(uint32_t RCC_RTCCLKSource)
+{
+  uint32_t tmpreg = 0;
+
+  /* Check the parameters */
+  assert_param(IS_RCC_RTCCLK_SOURCE(RCC_RTCCLKSource));
+
+  if ((RCC_RTCCLKSource & 0x00000300) == 0x00000300)
+  { /* If HSE is selected as RTC clock source, configure HSE division factor for RTC clock */
+    tmpreg = RCC->CFGR;
+
+    /* Clear RTCPRE[4:0] bits */
+    tmpreg &= ~RCC_CFGR_RTCPRE;
+
+    /* Configure HSE division factor for RTC clock */
+    tmpreg |= (RCC_RTCCLKSource & 0xFFFFCFF);
+
+    /* Store the new value */
+    RCC->CFGR = tmpreg;
+  }
+    
+  /* Select the RTC clock source */
+  RCC->BDCR |= (RCC_RTCCLKSource & 0x00000FFF);
+}
+
+/**
+  * @brief  Enables or disables the RTC clock.
+  * @note   This function must be used only after the RTC clock source was selected
+  *         using the RCC_RTCCLKConfig function.
+  * @param  NewState: new state of the RTC clock. This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_RTCCLKCmd(FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+  *(__IO uint32_t *) BDCR_RTCEN_BB = (uint32_t)NewState;
+}
+
+/**
+  * @brief  Forces or releases the Backup domain reset.
+  * @note   This function resets the RTC peripheral (including the backup registers)
+  *         and the RTC clock source selection in RCC_CSR register.
+  * @note   The BKPSRAM is not affected by this reset.    
+  * @param  NewState: new state of the Backup domain reset.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_BackupResetCmd(FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+  *(__IO uint32_t *) BDCR_BDRST_BB = (uint32_t)NewState;
+}
+
+/**
+  * @brief  Configures the I2S clock source (I2SCLK).
+  * @note   This function must be called before enabling the I2S APB clock.
+  * @param  RCC_I2SCLKSource: specifies the I2S clock source.
+  *          This parameter can be one of the following values:
+  *            @arg RCC_I2S2CLKSource_PLLI2S: PLLI2S clock used as I2S clock source
+  *            @arg RCC_I2S2CLKSource_Ext: External clock mapped on the I2S_CKIN pin
+  *                                        used as I2S clock source
+  * @retval None
+  */
+void RCC_I2SCLKConfig(uint32_t RCC_I2SCLKSource)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_I2SCLK_SOURCE(RCC_I2SCLKSource));
+
+  *(__IO uint32_t *) CFGR_I2SSRC_BB = RCC_I2SCLKSource;
+}
+
+/**
+  * @brief  Enables or disables the AHB1 peripheral clock.
+  * @note   After reset, the peripheral clock (used for registers read/write access)
+  *         is disabled and the application software has to enable this clock before 
+  *         using it.   
+  * @param  RCC_AHBPeriph: specifies the AHB1 peripheral to gates its clock.
+  *          This parameter can be any combination of the following values:
+  *            @arg RCC_AHB1Periph_GPIOA:       GPIOA clock
+  *            @arg RCC_AHB1Periph_GPIOB:       GPIOB clock 
+  *            @arg RCC_AHB1Periph_GPIOC:       GPIOC clock
+  *            @arg RCC_AHB1Periph_GPIOD:       GPIOD clock
+  *            @arg RCC_AHB1Periph_GPIOE:       GPIOE clock
+  *            @arg RCC_AHB1Periph_GPIOF:       GPIOF clock
+  *            @arg RCC_AHB1Periph_GPIOG:       GPIOG clock
+  *            @arg RCC_AHB1Periph_GPIOG:       GPIOG clock
+  *            @arg RCC_AHB1Periph_GPIOI:       GPIOI clock
+  *            @arg RCC_AHB1Periph_CRC:         CRC clock
+  *            @arg RCC_AHB1Periph_BKPSRAM:     BKPSRAM interface clock
+  *            @arg RCC_AHB1Periph_CCMDATARAMEN CCM data RAM interface clock
+  *            @arg RCC_AHB1Periph_DMA1:        DMA1 clock
+  *            @arg RCC_AHB1Periph_DMA2:        DMA2 clock
+  *            @arg RCC_AHB1Periph_ETH_MAC:     Ethernet MAC clock
+  *            @arg RCC_AHB1Periph_ETH_MAC_Tx:  Ethernet Transmission clock
+  *            @arg RCC_AHB1Periph_ETH_MAC_Rx:  Ethernet Reception clock
+  *            @arg RCC_AHB1Periph_ETH_MAC_PTP: Ethernet PTP clock
+  *            @arg RCC_AHB1Periph_OTG_HS:      USB OTG HS clock
+  *            @arg RCC_AHB1Periph_OTG_HS_ULPI: USB OTG HS ULPI clock
+  * @param  NewState: new state of the specified peripheral clock.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_AHB1PeriphClockCmd(uint32_t RCC_AHB1Periph, FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_AHB1_CLOCK_PERIPH(RCC_AHB1Periph));
+
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+  if (NewState != DISABLE)
+  {
+    RCC->AHB1ENR |= RCC_AHB1Periph;
+  }
+  else
+  {
+    RCC->AHB1ENR &= ~RCC_AHB1Periph;
+  }
+}
+
+/**
+  * @brief  Enables or disables the AHB2 peripheral clock.
+  * @note   After reset, the peripheral clock (used for registers read/write access)
+  *         is disabled and the application software has to enable this clock before 
+  *         using it. 
+  * @param  RCC_AHBPeriph: specifies the AHB2 peripheral to gates its clock.
+  *          This parameter can be any combination of the following values:
+  *            @arg RCC_AHB2Periph_DCMI:   DCMI clock
+  *            @arg RCC_AHB2Periph_CRYP:   CRYP clock
+  *            @arg RCC_AHB2Periph_HASH:   HASH clock
+  *            @arg RCC_AHB2Periph_RNG:    RNG clock
+  *            @arg RCC_AHB2Periph_OTG_FS: USB OTG FS clock
+  * @param  NewState: new state of the specified peripheral clock.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_AHB2PeriphClockCmd(uint32_t RCC_AHB2Periph, FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_AHB2_PERIPH(RCC_AHB2Periph));
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+  if (NewState != DISABLE)
+  {
+    RCC->AHB2ENR |= RCC_AHB2Periph;
+  }
+  else
+  {
+    RCC->AHB2ENR &= ~RCC_AHB2Periph;
+  }
+}
+
+/**
+  * @brief  Enables or disables the AHB3 peripheral clock.
+  * @note   After reset, the peripheral clock (used for registers read/write access)
+  *         is disabled and the application software has to enable this clock before 
+  *         using it. 
+  * @param  RCC_AHBPeriph: specifies the AHB3 peripheral to gates its clock.
+  *          This parameter must be: RCC_AHB3Periph_FSMC
+  * @param  NewState: new state of the specified peripheral clock.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_AHB3PeriphClockCmd(uint32_t RCC_AHB3Periph, FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_AHB3_PERIPH(RCC_AHB3Periph));  
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+  if (NewState != DISABLE)
+  {
+    RCC->AHB3ENR |= RCC_AHB3Periph;
+  }
+  else
+  {
+    RCC->AHB3ENR &= ~RCC_AHB3Periph;
+  }
+}
+
+/**
+  * @brief  Enables or disables the Low Speed APB (APB1) peripheral clock.
+  * @note   After reset, the peripheral clock (used for registers read/write access)
+  *         is disabled and the application software has to enable this clock before 
+  *         using it. 
+  * @param  RCC_APB1Periph: specifies the APB1 peripheral to gates its clock.
+  *          This parameter can be any combination of the following values:
+  *            @arg RCC_APB1Periph_TIM2:   TIM2 clock
+  *            @arg RCC_APB1Periph_TIM3:   TIM3 clock
+  *            @arg RCC_APB1Periph_TIM4:   TIM4 clock
+  *            @arg RCC_APB1Periph_TIM5:   TIM5 clock
+  *            @arg RCC_APB1Periph_TIM6:   TIM6 clock
+  *            @arg RCC_APB1Periph_TIM7:   TIM7 clock
+  *            @arg RCC_APB1Periph_TIM12:  TIM12 clock
+  *            @arg RCC_APB1Periph_TIM13:  TIM13 clock
+  *            @arg RCC_APB1Periph_TIM14:  TIM14 clock
+  *            @arg RCC_APB1Periph_WWDG:   WWDG clock
+  *            @arg RCC_APB1Periph_SPI2:   SPI2 clock
+  *            @arg RCC_APB1Periph_SPI3:   SPI3 clock
+  *            @arg RCC_APB1Periph_USART2: USART2 clock
+  *            @arg RCC_APB1Periph_USART3: USART3 clock
+  *            @arg RCC_APB1Periph_UART4:  UART4 clock
+  *            @arg RCC_APB1Periph_UART5:  UART5 clock
+  *            @arg RCC_APB1Periph_I2C1:   I2C1 clock
+  *            @arg RCC_APB1Periph_I2C2:   I2C2 clock
+  *            @arg RCC_APB1Periph_I2C3:   I2C3 clock
+  *            @arg RCC_APB1Periph_CAN1:   CAN1 clock
+  *            @arg RCC_APB1Periph_CAN2:   CAN2 clock
+  *            @arg RCC_APB1Periph_PWR:    PWR clock
+  *            @arg RCC_APB1Periph_DAC:    DAC clock
+  * @param  NewState: new state of the specified peripheral clock.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_APB1PeriphClockCmd(uint32_t RCC_APB1Periph, FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_APB1_PERIPH(RCC_APB1Periph));  
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+  if (NewState != DISABLE)
+  {
+    RCC->APB1ENR |= RCC_APB1Periph;
+  }
+  else
+  {
+    RCC->APB1ENR &= ~RCC_APB1Periph;
+  }
+}
+
+/**
+  * @brief  Enables or disables the High Speed APB (APB2) peripheral clock.
+  * @note   After reset, the peripheral clock (used for registers read/write access)
+  *         is disabled and the application software has to enable this clock before 
+  *         using it.
+  * @param  RCC_APB2Periph: specifies the APB2 peripheral to gates its clock.
+  *          This parameter can be any combination of the following values:
+  *            @arg RCC_APB2Periph_TIM1:   TIM1 clock
+  *            @arg RCC_APB2Periph_TIM8:   TIM8 clock
+  *            @arg RCC_APB2Periph_USART1: USART1 clock
+  *            @arg RCC_APB2Periph_USART6: USART6 clock
+  *            @arg RCC_APB2Periph_ADC1:   ADC1 clock
+  *            @arg RCC_APB2Periph_ADC2:   ADC2 clock
+  *            @arg RCC_APB2Periph_ADC3:   ADC3 clock
+  *            @arg RCC_APB2Periph_SDIO:   SDIO clock
+  *            @arg RCC_APB2Periph_SPI1:   SPI1 clock
+  *            @arg RCC_APB2Periph_SYSCFG: SYSCFG clock
+  *            @arg RCC_APB2Periph_TIM9:   TIM9 clock
+  *            @arg RCC_APB2Periph_TIM10:  TIM10 clock
+  *            @arg RCC_APB2Periph_TIM11:  TIM11 clock
+  * @param  NewState: new state of the specified peripheral clock.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_APB2PeriphClockCmd(uint32_t RCC_APB2Periph, FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_APB2_PERIPH(RCC_APB2Periph));
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+  if (NewState != DISABLE)
+  {
+    RCC->APB2ENR |= RCC_APB2Periph;
+  }
+  else
+  {
+    RCC->APB2ENR &= ~RCC_APB2Periph;
+  }
+}
+
+/**
+  * @brief  Forces or releases AHB1 peripheral reset.
+  * @param  RCC_AHB1Periph: specifies the AHB1 peripheral to reset.
+  *          This parameter can be any combination of the following values:
+  *            @arg RCC_AHB1Periph_GPIOA:   GPIOA clock
+  *            @arg RCC_AHB1Periph_GPIOB:   GPIOB clock 
+  *            @arg RCC_AHB1Periph_GPIOC:   GPIOC clock
+  *            @arg RCC_AHB1Periph_GPIOD:   GPIOD clock
+  *            @arg RCC_AHB1Periph_GPIOE:   GPIOE clock
+  *            @arg RCC_AHB1Periph_GPIOF:   GPIOF clock
+  *            @arg RCC_AHB1Periph_GPIOG:   GPIOG clock
+  *            @arg RCC_AHB1Periph_GPIOG:   GPIOG clock
+  *            @arg RCC_AHB1Periph_GPIOI:   GPIOI clock
+  *            @arg RCC_AHB1Periph_CRC:     CRC clock
+  *            @arg RCC_AHB1Periph_DMA1:    DMA1 clock
+  *            @arg RCC_AHB1Periph_DMA2:    DMA2 clock
+  *            @arg RCC_AHB1Periph_ETH_MAC: Ethernet MAC clock
+  *            @arg RCC_AHB1Periph_OTG_HS:  USB OTG HS clock
+  *                  
+  * @param  NewState: new state of the specified peripheral reset.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_AHB1PeriphResetCmd(uint32_t RCC_AHB1Periph, FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_AHB1_RESET_PERIPH(RCC_AHB1Periph));
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+  if (NewState != DISABLE)
+  {
+    RCC->AHB1RSTR |= RCC_AHB1Periph;
+  }
+  else
+  {
+    RCC->AHB1RSTR &= ~RCC_AHB1Periph;
+  }
+}
+
+/**
+  * @brief  Forces or releases AHB2 peripheral reset.
+  * @param  RCC_AHB2Periph: specifies the AHB2 peripheral to reset.
+  *          This parameter can be any combination of the following values:
+  *            @arg RCC_AHB2Periph_DCMI:   DCMI clock
+  *            @arg RCC_AHB2Periph_CRYP:   CRYP clock
+  *            @arg RCC_AHB2Periph_HASH:   HASH clock
+  *            @arg RCC_AHB2Periph_RNG:    RNG clock
+  *            @arg RCC_AHB2Periph_OTG_FS: USB OTG FS clock
+  * @param  NewState: new state of the specified peripheral reset.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_AHB2PeriphResetCmd(uint32_t RCC_AHB2Periph, FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_AHB2_PERIPH(RCC_AHB2Periph));
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+  if (NewState != DISABLE)
+  {
+    RCC->AHB2RSTR |= RCC_AHB2Periph;
+  }
+  else
+  {
+    RCC->AHB2RSTR &= ~RCC_AHB2Periph;
+  }
+}
+
+/**
+  * @brief  Forces or releases AHB3 peripheral reset.
+  * @param  RCC_AHB3Periph: specifies the AHB3 peripheral to reset.
+  *          This parameter must be: RCC_AHB3Periph_FSMC
+  * @param  NewState: new state of the specified peripheral reset.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_AHB3PeriphResetCmd(uint32_t RCC_AHB3Periph, FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_AHB3_PERIPH(RCC_AHB3Periph));
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+
+  if (NewState != DISABLE)
+  {
+    RCC->AHB3RSTR |= RCC_AHB3Periph;
+  }
+  else
+  {
+    RCC->AHB3RSTR &= ~RCC_AHB3Periph;
+  }
+}
+
+/**
+  * @brief  Forces or releases Low Speed APB (APB1) peripheral reset.
+  * @param  RCC_APB1Periph: specifies the APB1 peripheral to reset.
+  *          This parameter can be any combination of the following values:
+  *            @arg RCC_APB1Periph_TIM2:   TIM2 clock
+  *            @arg RCC_APB1Periph_TIM3:   TIM3 clock
+  *            @arg RCC_APB1Periph_TIM4:   TIM4 clock
+  *            @arg RCC_APB1Periph_TIM5:   TIM5 clock
+  *            @arg RCC_APB1Periph_TIM6:   TIM6 clock
+  *            @arg RCC_APB1Periph_TIM7:   TIM7 clock
+  *            @arg RCC_APB1Periph_TIM12:  TIM12 clock
+  *            @arg RCC_APB1Periph_TIM13:  TIM13 clock
+  *            @arg RCC_APB1Periph_TIM14:  TIM14 clock
+  *            @arg RCC_APB1Periph_WWDG:   WWDG clock
+  *            @arg RCC_APB1Periph_SPI2:   SPI2 clock
+  *            @arg RCC_APB1Periph_SPI3:   SPI3 clock
+  *            @arg RCC_APB1Periph_USART2: USART2 clock
+  *            @arg RCC_APB1Periph_USART3: USART3 clock
+  *            @arg RCC_APB1Periph_UART4:  UART4 clock
+  *            @arg RCC_APB1Periph_UART5:  UART5 clock
+  *            @arg RCC_APB1Periph_I2C1:   I2C1 clock
+  *            @arg RCC_APB1Periph_I2C2:   I2C2 clock
+  *            @arg RCC_APB1Periph_I2C3:   I2C3 clock
+  *            @arg RCC_APB1Periph_CAN1:   CAN1 clock
+  *            @arg RCC_APB1Periph_CAN2:   CAN2 clock
+  *            @arg RCC_APB1Periph_PWR:    PWR clock
+  *            @arg RCC_APB1Periph_DAC:    DAC clock
+  * @param  NewState: new state of the specified peripheral reset.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_APB1PeriphResetCmd(uint32_t RCC_APB1Periph, FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_APB1_PERIPH(RCC_APB1Periph));
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+  if (NewState != DISABLE)
+  {
+    RCC->APB1RSTR |= RCC_APB1Periph;
+  }
+  else
+  {
+    RCC->APB1RSTR &= ~RCC_APB1Periph;
+  }
+}
+
+/**
+  * @brief  Forces or releases High Speed APB (APB2) peripheral reset.
+  * @param  RCC_APB2Periph: specifies the APB2 peripheral to reset.
+  *          This parameter can be any combination of the following values:
+  *            @arg RCC_APB2Periph_TIM1:   TIM1 clock
+  *            @arg RCC_APB2Periph_TIM8:   TIM8 clock
+  *            @arg RCC_APB2Periph_USART1: USART1 clock
+  *            @arg RCC_APB2Periph_USART6: USART6 clock
+  *            @arg RCC_APB2Periph_ADC1:   ADC1 clock
+  *            @arg RCC_APB2Periph_ADC2:   ADC2 clock
+  *            @arg RCC_APB2Periph_ADC3:   ADC3 clock
+  *            @arg RCC_APB2Periph_SDIO:   SDIO clock
+  *            @arg RCC_APB2Periph_SPI1:   SPI1 clock
+  *            @arg RCC_APB2Periph_SYSCFG: SYSCFG clock
+  *            @arg RCC_APB2Periph_TIM9:   TIM9 clock
+  *            @arg RCC_APB2Periph_TIM10:  TIM10 clock
+  *            @arg RCC_APB2Periph_TIM11:  TIM11 clock
+  * @param  NewState: new state of the specified peripheral reset.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_APB2PeriphResetCmd(uint32_t RCC_APB2Periph, FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_APB2_RESET_PERIPH(RCC_APB2Periph));
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+  if (NewState != DISABLE)
+  {
+    RCC->APB2RSTR |= RCC_APB2Periph;
+  }
+  else
+  {
+    RCC->APB2RSTR &= ~RCC_APB2Periph;
+  }
+}
+
+/**
+  * @brief  Enables or disables the AHB1 peripheral clock during Low Power (Sleep) mode.
+  * @note   Peripheral clock gating in SLEEP mode can be used to further reduce
+  *         power consumption.
+  * @note   After wakeup from SLEEP mode, the peripheral clock is enabled again.
+  * @note   By default, all peripheral clocks are enabled during SLEEP mode.
+  * @param  RCC_AHBPeriph: specifies the AHB1 peripheral to gates its clock.
+  *          This parameter can be any combination of the following values:
+  *            @arg RCC_AHB1Periph_GPIOA:       GPIOA clock
+  *            @arg RCC_AHB1Periph_GPIOB:       GPIOB clock 
+  *            @arg RCC_AHB1Periph_GPIOC:       GPIOC clock
+  *            @arg RCC_AHB1Periph_GPIOD:       GPIOD clock
+  *            @arg RCC_AHB1Periph_GPIOE:       GPIOE clock
+  *            @arg RCC_AHB1Periph_GPIOF:       GPIOF clock
+  *            @arg RCC_AHB1Periph_GPIOG:       GPIOG clock
+  *            @arg RCC_AHB1Periph_GPIOG:       GPIOG clock
+  *            @arg RCC_AHB1Periph_GPIOI:       GPIOI clock
+  *            @arg RCC_AHB1Periph_CRC:         CRC clock
+  *            @arg RCC_AHB1Periph_BKPSRAM:     BKPSRAM interface clock
+  *            @arg RCC_AHB1Periph_DMA1:        DMA1 clock
+  *            @arg RCC_AHB1Periph_DMA2:        DMA2 clock
+  *            @arg RCC_AHB1Periph_ETH_MAC:     Ethernet MAC clock
+  *            @arg RCC_AHB1Periph_ETH_MAC_Tx:  Ethernet Transmission clock
+  *            @arg RCC_AHB1Periph_ETH_MAC_Rx:  Ethernet Reception clock
+  *            @arg RCC_AHB1Periph_ETH_MAC_PTP: Ethernet PTP clock
+  *            @arg RCC_AHB1Periph_OTG_HS:      USB OTG HS clock
+  *            @arg RCC_AHB1Periph_OTG_HS_ULPI: USB OTG HS ULPI clock
+  * @param  NewState: new state of the specified peripheral clock.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_AHB1PeriphClockLPModeCmd(uint32_t RCC_AHB1Periph, FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_AHB1_LPMODE_PERIPH(RCC_AHB1Periph));
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+  if (NewState != DISABLE)
+  {
+    RCC->AHB1LPENR |= RCC_AHB1Periph;
+  }
+  else
+  {
+    RCC->AHB1LPENR &= ~RCC_AHB1Periph;
+  }
+}
+
+/**
+  * @brief  Enables or disables the AHB2 peripheral clock during Low Power (Sleep) mode.
+  * @note   Peripheral clock gating in SLEEP mode can be used to further reduce
+  *           power consumption.
+  * @note   After wakeup from SLEEP mode, the peripheral clock is enabled again.
+  * @note   By default, all peripheral clocks are enabled during SLEEP mode.
+  * @param  RCC_AHBPeriph: specifies the AHB2 peripheral to gates its clock.
+  *          This parameter can be any combination of the following values:
+  *            @arg RCC_AHB2Periph_DCMI:   DCMI clock
+  *            @arg RCC_AHB2Periph_CRYP:   CRYP clock
+  *            @arg RCC_AHB2Periph_HASH:   HASH clock
+  *            @arg RCC_AHB2Periph_RNG:    RNG clock
+  *            @arg RCC_AHB2Periph_OTG_FS: USB OTG FS clock  
+  * @param  NewState: new state of the specified peripheral clock.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_AHB2PeriphClockLPModeCmd(uint32_t RCC_AHB2Periph, FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_AHB2_PERIPH(RCC_AHB2Periph));
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+  if (NewState != DISABLE)
+  {
+    RCC->AHB2LPENR |= RCC_AHB2Periph;
+  }
+  else
+  {
+    RCC->AHB2LPENR &= ~RCC_AHB2Periph;
+  }
+}
+
+/**
+  * @brief  Enables or disables the AHB3 peripheral clock during Low Power (Sleep) mode.
+  * @note   Peripheral clock gating in SLEEP mode can be used to further reduce
+  *         power consumption.
+  * @note   After wakeup from SLEEP mode, the peripheral clock is enabled again.
+  * @note   By default, all peripheral clocks are enabled during SLEEP mode.
+  * @param  RCC_AHBPeriph: specifies the AHB3 peripheral to gates its clock.
+  *          This parameter must be: RCC_AHB3Periph_FSMC
+  * @param  NewState: new state of the specified peripheral clock.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_AHB3PeriphClockLPModeCmd(uint32_t RCC_AHB3Periph, FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_AHB3_PERIPH(RCC_AHB3Periph));
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+  if (NewState != DISABLE)
+  {
+    RCC->AHB3LPENR |= RCC_AHB3Periph;
+  }
+  else
+  {
+    RCC->AHB3LPENR &= ~RCC_AHB3Periph;
+  }
+}
+
+/**
+  * @brief  Enables or disables the APB1 peripheral clock during Low Power (Sleep) mode.
+  * @note   Peripheral clock gating in SLEEP mode can be used to further reduce
+  *         power consumption.
+  * @note   After wakeup from SLEEP mode, the peripheral clock is enabled again.
+  * @note   By default, all peripheral clocks are enabled during SLEEP mode.
+  * @param  RCC_APB1Periph: specifies the APB1 peripheral to gates its clock.
+  *          This parameter can be any combination of the following values:
+  *            @arg RCC_APB1Periph_TIM2:   TIM2 clock
+  *            @arg RCC_APB1Periph_TIM3:   TIM3 clock
+  *            @arg RCC_APB1Periph_TIM4:   TIM4 clock
+  *            @arg RCC_APB1Periph_TIM5:   TIM5 clock
+  *            @arg RCC_APB1Periph_TIM6:   TIM6 clock
+  *            @arg RCC_APB1Periph_TIM7:   TIM7 clock
+  *            @arg RCC_APB1Periph_TIM12:  TIM12 clock
+  *            @arg RCC_APB1Periph_TIM13:  TIM13 clock
+  *            @arg RCC_APB1Periph_TIM14:  TIM14 clock
+  *            @arg RCC_APB1Periph_WWDG:   WWDG clock
+  *            @arg RCC_APB1Periph_SPI2:   SPI2 clock
+  *            @arg RCC_APB1Periph_SPI3:   SPI3 clock
+  *            @arg RCC_APB1Periph_USART2: USART2 clock
+  *            @arg RCC_APB1Periph_USART3: USART3 clock
+  *            @arg RCC_APB1Periph_UART4:  UART4 clock
+  *            @arg RCC_APB1Periph_UART5:  UART5 clock
+  *            @arg RCC_APB1Periph_I2C1:   I2C1 clock
+  *            @arg RCC_APB1Periph_I2C2:   I2C2 clock
+  *            @arg RCC_APB1Periph_I2C3:   I2C3 clock
+  *            @arg RCC_APB1Periph_CAN1:   CAN1 clock
+  *            @arg RCC_APB1Periph_CAN2:   CAN2 clock
+  *            @arg RCC_APB1Periph_PWR:    PWR clock
+  *            @arg RCC_APB1Periph_DAC:    DAC clock
+  * @param  NewState: new state of the specified peripheral clock.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_APB1PeriphClockLPModeCmd(uint32_t RCC_APB1Periph, FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_APB1_PERIPH(RCC_APB1Periph));
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+  if (NewState != DISABLE)
+  {
+    RCC->APB1LPENR |= RCC_APB1Periph;
+  }
+  else
+  {
+    RCC->APB1LPENR &= ~RCC_APB1Periph;
+  }
+}
+
+/**
+  * @brief  Enables or disables the APB2 peripheral clock during Low Power (Sleep) mode.
+  * @note   Peripheral clock gating in SLEEP mode can be used to further reduce
+  *         power consumption.
+  * @note   After wakeup from SLEEP mode, the peripheral clock is enabled again.
+  * @note   By default, all peripheral clocks are enabled during SLEEP mode.
+  * @param  RCC_APB2Periph: specifies the APB2 peripheral to gates its clock.
+  *          This parameter can be any combination of the following values:
+  *            @arg RCC_APB2Periph_TIM1:   TIM1 clock
+  *            @arg RCC_APB2Periph_TIM8:   TIM8 clock
+  *            @arg RCC_APB2Periph_USART1: USART1 clock
+  *            @arg RCC_APB2Periph_USART6: USART6 clock
+  *            @arg RCC_APB2Periph_ADC1:   ADC1 clock
+  *            @arg RCC_APB2Periph_ADC2:   ADC2 clock
+  *            @arg RCC_APB2Periph_ADC3:   ADC3 clock
+  *            @arg RCC_APB2Periph_SDIO:   SDIO clock
+  *            @arg RCC_APB2Periph_SPI1:   SPI1 clock
+  *            @arg RCC_APB2Periph_SYSCFG: SYSCFG clock
+  *            @arg RCC_APB2Periph_TIM9:   TIM9 clock
+  *            @arg RCC_APB2Periph_TIM10:  TIM10 clock
+  *            @arg RCC_APB2Periph_TIM11:  TIM11 clock
+  * @param  NewState: new state of the specified peripheral clock.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_APB2PeriphClockLPModeCmd(uint32_t RCC_APB2Periph, FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_APB2_PERIPH(RCC_APB2Periph));
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+  if (NewState != DISABLE)
+  {
+    RCC->APB2LPENR |= RCC_APB2Periph;
+  }
+  else
+  {
+    RCC->APB2LPENR &= ~RCC_APB2Periph;
+  }
+}
+
+/**
+  * @}
+  */
+
+/** @defgroup RCC_Group4 Interrupts and flags management functions
+ *  @brief   Interrupts and flags management functions 
+ *
+@verbatim   
+ ===============================================================================
+                   Interrupts and flags management functions
+ ===============================================================================  
+
+@endverbatim
+  * @{
+  */
+
+/**
+  * @brief  Enables or disables the specified RCC interrupts.
+  * @param  RCC_IT: specifies the RCC interrupt sources to be enabled or disabled.
+  *          This parameter can be any combination of the following values:
+  *            @arg RCC_IT_LSIRDY: LSI ready interrupt
+  *            @arg RCC_IT_LSERDY: LSE ready interrupt
+  *            @arg RCC_IT_HSIRDY: HSI ready interrupt
+  *            @arg RCC_IT_HSERDY: HSE ready interrupt
+  *            @arg RCC_IT_PLLRDY: main PLL ready interrupt
+  *            @arg RCC_IT_PLLI2SRDY: PLLI2S ready interrupt  
+  * @param  NewState: new state of the specified RCC interrupts.
+  *          This parameter can be: ENABLE or DISABLE.
+  * @retval None
+  */
+void RCC_ITConfig(uint8_t RCC_IT, FunctionalState NewState)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_IT(RCC_IT));
+  assert_param(IS_FUNCTIONAL_STATE(NewState));
+  if (NewState != DISABLE)
+  {
+    /* Perform Byte access to RCC_CIR[14:8] bits to enable the selected interrupts */
+    *(__IO uint8_t *) CIR_BYTE2_ADDRESS |= RCC_IT;
+  }
+  else
+  {
+    /* Perform Byte access to RCC_CIR[14:8] bits to disable the selected interrupts */
+    *(__IO uint8_t *) CIR_BYTE2_ADDRESS &= (uint8_t)~RCC_IT;
+  }
+}
+
+/**
+  * @brief  Checks whether the specified RCC flag is set or not.
+  * @param  RCC_FLAG: specifies the flag to check.
+  *          This parameter can be one of the following values:
+  *            @arg RCC_FLAG_HSIRDY: HSI oscillator clock ready
+  *            @arg RCC_FLAG_HSERDY: HSE oscillator clock ready
+  *            @arg RCC_FLAG_PLLRDY: main PLL clock ready
+  *            @arg RCC_FLAG_PLLI2SRDY: PLLI2S clock ready
+  *            @arg RCC_FLAG_LSERDY: LSE oscillator clock ready
+  *            @arg RCC_FLAG_LSIRDY: LSI oscillator clock ready
+  *            @arg RCC_FLAG_BORRST: POR/PDR or BOR reset
+  *            @arg RCC_FLAG_PINRST: Pin reset
+  *            @arg RCC_FLAG_PORRST: POR/PDR reset
+  *            @arg RCC_FLAG_SFTRST: Software reset
+  *            @arg RCC_FLAG_IWDGRST: Independent Watchdog reset
+  *            @arg RCC_FLAG_WWDGRST: Window Watchdog reset
+  *            @arg RCC_FLAG_LPWRRST: Low Power reset
+  * @retval The new state of RCC_FLAG (SET or RESET).
+  */
+FlagStatus RCC_GetFlagStatus(uint8_t RCC_FLAG)
+{
+  uint32_t tmp = 0;
+  uint32_t statusreg = 0;
+  FlagStatus bitstatus = RESET;
+
+  /* Check the parameters */
+  assert_param(IS_RCC_FLAG(RCC_FLAG));
+
+  /* Get the RCC register index */
+  tmp = RCC_FLAG >> 5;
+  if (tmp == 1)               /* The flag to check is in CR register */
+  {
+    statusreg = RCC->CR;
+  }
+  else if (tmp == 2)          /* The flag to check is in BDCR register */
+  {
+    statusreg = RCC->BDCR;
+  }
+  else                       /* The flag to check is in CSR register */
+  {
+    statusreg = RCC->CSR;
+  }
+
+  /* Get the flag position */
+  tmp = RCC_FLAG & FLAG_MASK;
+  if ((statusreg & ((uint32_t)1 << tmp)) != (uint32_t)RESET)
+  {
+    bitstatus = SET;
+  }
+  else
+  {
+    bitstatus = RESET;
+  }
+  /* Return the flag status */
+  return bitstatus;
+}
+
+/**
+  * @brief  Clears the RCC reset flags.
+  *         The reset flags are: RCC_FLAG_PINRST, RCC_FLAG_PORRST,  RCC_FLAG_SFTRST,
+  *         RCC_FLAG_IWDGRST, RCC_FLAG_WWDGRST, RCC_FLAG_LPWRRST
+  * @param  None
+  * @retval None
+  */
+void RCC_ClearFlag(void)
+{
+  /* Set RMVF bit to clear the reset flags */
+  RCC->CSR |= RCC_CSR_RMVF;
+}
+
+/**
+  * @brief  Checks whether the specified RCC interrupt has occurred or not.
+  * @param  RCC_IT: specifies the RCC interrupt source to check.
+  *          This parameter can be one of the following values:
+  *            @arg RCC_IT_LSIRDY: LSI ready interrupt
+  *            @arg RCC_IT_LSERDY: LSE ready interrupt
+  *            @arg RCC_IT_HSIRDY: HSI ready interrupt
+  *            @arg RCC_IT_HSERDY: HSE ready interrupt
+  *            @arg RCC_IT_PLLRDY: main PLL ready interrupt
+  *            @arg RCC_IT_PLLI2SRDY: PLLI2S ready interrupt  
+  *            @arg RCC_IT_CSS: Clock Security System interrupt
+  * @retval The new state of RCC_IT (SET or RESET).
+  */
+ITStatus RCC_GetITStatus(uint8_t RCC_IT)
+{
+  ITStatus bitstatus = RESET;
+
+  /* Check the parameters */
+  assert_param(IS_RCC_GET_IT(RCC_IT));
+
+  /* Check the status of the specified RCC interrupt */
+  if ((RCC->CIR & RCC_IT) != (uint32_t)RESET)
+  {
+    bitstatus = SET;
+  }
+  else
+  {
+    bitstatus = RESET;
+  }
+  /* Return the RCC_IT status */
+  return  bitstatus;
+}
+
+/**
+  * @brief  Clears the RCC's interrupt pending bits.
+  * @param  RCC_IT: specifies the interrupt pending bit to clear.
+  *          This parameter can be any combination of the following values:
+  *            @arg RCC_IT_LSIRDY: LSI ready interrupt
+  *            @arg RCC_IT_LSERDY: LSE ready interrupt
+  *            @arg RCC_IT_HSIRDY: HSI ready interrupt
+  *            @arg RCC_IT_HSERDY: HSE ready interrupt
+  *            @arg RCC_IT_PLLRDY: main PLL ready interrupt
+  *            @arg RCC_IT_PLLI2SRDY: PLLI2S ready interrupt  
+  *            @arg RCC_IT_CSS: Clock Security System interrupt
+  * @retval None
+  */
+void RCC_ClearITPendingBit(uint8_t RCC_IT)
+{
+  /* Check the parameters */
+  assert_param(IS_RCC_CLEAR_IT(RCC_IT));
+
+  /* Perform Byte access to RCC_CIR[23:16] bits to clear the selected interrupt
+     pending bits */
+  *(__IO uint8_t *) CIR_BYTE3_ADDRESS = RCC_IT;
+}
+
+/**
+  * @}
+  */ 
+
+/**
+  * @}
+  */ 
+
+/**
+  * @}
+  */ 
+
+/**
+  * @}
+  */ 
+
+/******************* (C) COPYRIGHT 2011 STMicroelectronics *****END OF FILE****/
+