text: /**
    ******************************************************************************
    * @file    system_stm32f4xx.c
    * @author  MCD Application Team
    * @version V2.3.2
    * @date    26-June-2015
    * @brief   CMSIS Cortex-M4 Device Peripheral Access Layer System Source File.
    *
    *   This file provides two functions and one global variable to be called from 
    *   user application:
    *      - SystemInit(): This function is called at startup just after reset and 
    *                      before branch to main program. This call is made inside
    *                      the "startup_stm32f4xx.s" file.
    *
    *      - SystemCoreClock variable: Contains the core clock (HCLK), it can be used
    *                                  by the user application to setup the SysTick 
    *                                  timer or configure other parameters.
    *                                     
    *      - SystemCoreClockUpdate(): Updates the variable SystemCoreClock and must
    *                                 be called whenever the core clock is changed
    *                                 during program execution.
    *
    * This file configures the system clock as follows:
    *-----------------------------------------------------------------------------
    * System clock source                | 1- PLL_HSE_EXTC        | 3- PLL_HSI
    *                                    | (external 8 MHz clock) | (internal 16 MHz)
    *                                    | 2- PLL_HSE_XTAL        |
    *                                    | (external 8 MHz xtal)  |
    *-----------------------------------------------------------------------------
    * SYSCLK(MHz)                        | 180                    | 180
    *-----------------------------------------------------------------------------
    * AHBCLK (MHz)                       | 180                    | 180
    *-----------------------------------------------------------------------------
    * APB1CLK (MHz)                      |  45                    |  45
    *-----------------------------------------------------------------------------
    * APB2CLK (MHz)                      |  90                    |  90
    *-----------------------------------------------------------------------------
    * USB capable (48 MHz precise clock) | YES                    |  NO
    *-----------------------------------------------------------------------------  
    ******************************************************************************
    * @attention
    *
    * <h2><center>&copy; COPYRIGHT 2015 STMicroelectronics</center></h2>
    *
    * Redistribution and use in source and binary forms, with or without modification,
    * are permitted provided that the following conditions are met:
    *   1. Redistributions of source code must retain the above copyright notice,
    *      this list of conditions and the following disclaimer.
    *   2. Redistributions in binary form must reproduce the above copyright notice,
    *      this list of conditions and the following disclaimer in the documentation
    *      and/or other materials provided with the distribution.
    *   3. Neither the name of STMicroelectronics nor the names of its contributors
    *      may be used to endorse or promote products derived from this software
    *      without specific prior written permission.
    *
    * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
    * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
    * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
    * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
    * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
    * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
    * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
    * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
    *
    ******************************************************************************
    */
  
  /** @addtogroup CMSIS
    * @{
    */
  
  /** @addtogroup stm32f4xx_system
    * @{
    */  
    
  /** @addtogroup STM32F4xx_System_Private_Includes
    * @{
    */
  
  
  #include "stm32f4xx.h"
  #include "hal_tick.h"
  
  #if !defined  (HSE_VALUE) 
    #define HSE_VALUE    ((uint32_t)8000000) /*!< Default value of the External oscillator in Hz */
  #endif /* HSE_VALUE */
  
  #if !defined  (HSI_VALUE)
    #define HSI_VALUE    ((uint32_t)16000000) /*!< Value of the Internal oscillator in Hz*/
  #endif /* HSI_VALUE */
  
  /**
    * @}
    */
  
  /** @addtogroup STM32F4xx_System_Private_TypesDefinitions
    * @{
    */
  
  /**
    * @}
    */
  
  /** @addtogroup STM32F4xx_System_Private_Defines
    * @{
    */
  
  /************************* Miscellaneous Configuration ************************/
  /*!< Uncomment the following line if you need to use external SRAM or SDRAM as data memory  */
  #if defined(STM32F405xx) || defined(STM32F415xx) || defined(STM32F407xx) || defined(STM32F417xx) ||\
      defined(STM32F427xx) || defined(STM32F437xx) || defined(STM32F429xx) || defined(STM32F439xx)
  /* #define DATA_IN_ExtSRAM */
  #endif /* STM32F40xxx || STM32F41xxx || STM32F42xxx || STM32F43xxx */
   
  #if defined(STM32F427xx) || defined(STM32F437xx) || defined(STM32F429xx) || defined(STM32F439xx) ||\
      defined(STM32F446xx)
  /* #define DATA_IN_ExtSDRAM */
  #endif /* STM32F427xx || STM32F437xx || STM32F429xx || STM32F439xx || STM32F446xx */
  
  #if defined(DATA_IN_ExtSRAM) && defined(DATA_IN_ExtSDRAM)
   #error "Please select DATA_IN_ExtSRAM or DATA_IN_ExtSDRAM " 
  #endif /* DATA_IN_ExtSRAM && DATA_IN_ExtSDRAM */
  
  /*!< Uncomment the following line if you need to relocate your vector Table in
       Internal SRAM. */
  /* #define VECT_TAB_SRAM */
  #define VECT_TAB_OFFSET  0x00 /*!< Vector Table base offset field. 
                                     This value must be a multiple of 0x200. */
  /******************************************************************************/
  
  /**
    * @}
    */
  
  /** @addtogroup STM32F4xx_System_Private_Macros
    * @{
    */
  
  /* Select the clock sources (other than HSI) to start with (0=OFF, 1=ON) */
  #define USE_PLL_HSE_EXTC (1) /* Use external clock */
  #define USE_PLL_HSE_XTAL (0) /* Use external xtal */
  #define DEBUG_MCO        (1) // Output the MCO1/MCO2 on PA8/PC9 for debugging (0=OFF, 1=ON)
  
  /**
    * @}
    */
  
  /** @addtogroup STM32F4xx_System_Private_Variables
    * @{
    */
    /* This variable is updated in three ways:
        1) by calling CMSIS function SystemCoreClockUpdate()
        2) by calling HAL API function HAL_RCC_GetHCLKFreq()
        3) each time HAL_RCC_ClockConfig() is called to configure the system clock frequency 
           Note: If you use this function to configure the system clock; then there
                 is no need to call the 2 first functions listed above, since SystemCoreClock
                 variable is updated automatically.
    */
  uint32_t SystemCoreClock = 16000000;
  const uint8_t AHBPrescTable[16] = {0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 7, 8, 9};
  
  /**
    * @}
    */
  
  /** @addtogroup STM32F4xx_System_Private_FunctionPrototypes
    * @{
    */
  
  #if defined (DATA_IN_ExtSRAM) || defined (DATA_IN_ExtSDRAM)
    static void SystemInit_ExtMemCtl(void); 
  #endif /* DATA_IN_ExtSRAM || DATA_IN_ExtSDRAM */
  
  #if (USE_PLL_HSE_XTAL != 0) || (USE_PLL_HSE_EXTC != 0)
  uint8_t SetSysClock_PLL_HSE(uint8_t bypass);
  #endif
  
  uint8_t SetSysClock_PLL_HSI(void);
  
  /**
    * @}
    */
  
  /** @addtogroup STM32F4xx_System_Private_Functions
    * @{
    */
  
  /**
    * @brief  Setup the microcontroller system
    *         Initialize the FPU setting, vector table location and External memory 
    *         configuration.
    * @param  None
    * @retval None
    */
  void SystemInit(void)
  {
    /* FPU settings ------------------------------------------------------------*/
    #if (__FPU_PRESENT == 1) && (__FPU_USED == 1)
      SCB->CPACR |= ((3UL << 10*2)|(3UL << 11*2));  /* set CP10 and CP11 Full Access */
    #endif
    /* Reset the RCC clock configuration to the default reset state ------------*/
    /* 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;
  
  #if defined (DATA_IN_ExtSRAM) || defined (DATA_IN_ExtSDRAM)
    SystemInit_ExtMemCtl(); 
  #endif /* DATA_IN_ExtSRAM || DATA_IN_ExtSDRAM */
  
    /* Configure the Vector Table location add offset address ------------------*/
  #ifdef VECT_TAB_SRAM
    SCB->VTOR = SRAM_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal SRAM */
  #else
    SCB->VTOR = FLASH_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal FLASH */
  #endif
  
    /* Configure the Cube driver */
    SystemCoreClock = 18000000; // At this stage the HSI is used as system clock
    HAL_Init();
  
    /* Configure the System clock source, PLL Multiplier and Divider factors,
       AHB/APBx prescalers and Flash settings */
    SetSysClock();
    
    /* Reset the timer to avoid issues after the RAM initialization */
    TIM_MST_RESET_ON;
    TIM_MST_RESET_OFF;  
  }
  
  /**
     * @brief  Update SystemCoreClock variable according to Clock Register Values.
    *         The SystemCoreClock variable contains the core clock (HCLK), it can
    *         be used by the user application to setup the SysTick timer or configure
    *         other parameters.
    *           
    * @note   Each time the core clock (HCLK) changes, this function must be called
    *         to update SystemCoreClock variable value. Otherwise, any configuration
    *         based on this variable will be incorrect.         
    *     
    * @note   - The system frequency computed by this function is not the real 
    *           frequency in the chip. It is calculated based on the predefined 
    *           constant and the selected clock source:
    *             
    *           - If SYSCLK source is HSI, SystemCoreClock will contain the HSI_VALUE(*)
    *                                              
    *           - If SYSCLK source is HSE, SystemCoreClock will contain the HSE_VALUE(**)
    *                          
    *           - If SYSCLK source is PLL, SystemCoreClock will contain the HSE_VALUE(**) 
    *             or HSI_VALUE(*) multiplied/divided by the PLL factors.
    *         
    *         (*) HSI_VALUE is a constant defined in stm32f4xx_hal_conf.h file (default value
    *             16 MHz) but the real value may vary depending on the variations
    *             in voltage and temperature.   
    *    
    *         (**) HSE_VALUE is a constant defined in stm32f4xx_hal_conf.h file (its value
    *              depends on the application requirements), user has to ensure that HSE_VALUE
    *              is same as the real frequency of the crystal used. Otherwise, this function
    *              may have wrong result.
    *                
    *         - The result of this function could be not correct when using fractional
    *           value for HSE crystal.
    *     
    * @param  None
    * @retval None
    */
  void SystemCoreClockUpdate(void)
  {
    uint32_t tmp = 0, 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 */
        SystemCoreClock = HSI_VALUE;
        break;
      case 0x04:  /* HSE used as system clock source */
        SystemCoreClock = HSE_VALUE;
        break;
      case 0x08:  /* PLL used as system clock source */
  
        /* PLL_VCO = (HSE_VALUE or HSI_VALUE / PLL_M) * PLL_N
           SYSCLK = PLL_VCO / PLL_P
           */    
        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;
        SystemCoreClock = pllvco/pllp;
        break;
      default:
        SystemCoreClock = HSI_VALUE;
        break;
    }
    /* Compute HCLK frequency --------------------------------------------------*/
    /* Get HCLK prescaler */
    tmp = AHBPrescTable[((RCC->CFGR & RCC_CFGR_HPRE) >> 4)];
    /* HCLK frequency */
    SystemCoreClock >>= tmp;
  }
  
  #if defined (DATA_IN_ExtSRAM) || defined (DATA_IN_ExtSDRAM)
  /**
    * @brief  Setup the external memory controller.
    *         Called in startup_stm32f4xx.s before jump to main.
    *         This function configures the external memories (SRAM/SDRAM)
    *         This SRAM/SDRAM will be used as program data memory (including heap and stack).
    * @param  None
    * @retval None
    */
  void SystemInit_ExtMemCtl(void)
  {
    __IO uint32_t tmp = 0x00;
  #if defined(STM32F427xx) || defined(STM32F437xx) || defined(STM32F429xx) || defined(STM32F439xx) || defined(STM32F446xx)
  #if defined (DATA_IN_ExtSDRAM)
    register uint32_t tmpreg = 0, timeout = 0xFFFF;
    register uint32_t index;
  
  #if defined(STM32F446xx)
    /* Enable GPIOA, GPIOC, GPIOD, GPIOE, GPIOF, GPIOG interface
        clock */
    RCC->AHB1ENR |= 0x0000007D;
  #else
    /* Enable GPIOC, GPIOD, GPIOE, GPIOF, GPIOG, GPIOH and GPIOI interface 
        clock */
    RCC->AHB1ENR |= 0x000001F8;
  #endif /* STM32F446xx */  
    /* Delay after an RCC peripheral clock enabling */
    tmp = READ_BIT(RCC->AHB1ENR, RCC_AHB1ENR_GPIOCEN);
    
  #if defined(STM32F446xx)
    /* Connect PAx pins to FMC Alternate function */
    GPIOA->AFR[0]  |= 0xC0000000;
    GPIOA->AFR[1]  |= 0x00000000;
    /* Configure PDx pins in Alternate function mode */
    GPIOA->MODER   |= 0x00008000;
    /* Configure PDx pins speed to 50 MHz */
    GPIOA->OSPEEDR |= 0x00008000;
    /* Configure PDx pins Output type to push-pull */
    GPIOA->OTYPER  |= 0x00000000;
    /* No pull-up, pull-down for PDx pins */
    GPIOA->PUPDR   |= 0x00000000;
  
    /* Connect PCx pins to FMC Alternate function */
    GPIOC->AFR[0]  |= 0x00CC0000;
    GPIOC->AFR[1]  |= 0x00000000;
    /* Configure PDx pins in Alternate function mode */
    GPIOC->MODER   |= 0x00000A00;
    /* Configure PDx pins speed to 50 MHz */
    GPIOC->OSPEEDR |= 0x00000A00;
    /* Configure PDx pins Output type to push-pull */
    GPIOC->OTYPER  |= 0x00000000;
    /* No pull-up, pull-down for PDx pins */
    GPIOC->PUPDR   |= 0x00000000;
  #endif /* STM32F446xx */
  
    /* Connect PDx pins to FMC Alternate function */
    GPIOD->AFR[0]  = 0x000000CC;
    GPIOD->AFR[1]  = 0xCC000CCC;
    /* Configure PDx pins in Alternate function mode */  
    GPIOD->MODER   = 0xA02A000A;
    /* Configure PDx pins speed to 50 MHz */  
    GPIOD->OSPEEDR = 0xA02A000A;
    /* Configure PDx pins Output type to push-pull */  
    GPIOD->OTYPER  = 0x00000000;
    /* No pull-up, pull-down for PDx pins */ 
    GPIOD->PUPDR   = 0x00000000;
  
    /* Connect PEx pins to FMC Alternate function */
    GPIOE->AFR[0]  = 0xC00000CC;
    GPIOE->AFR[1]  = 0xCCCCCCCC;
    /* Configure PEx pins in Alternate function mode */ 
    GPIOE->MODER   = 0xAAAA800A;
    /* Configure PEx pins speed to 50 MHz */ 
    GPIOE->OSPEEDR = 0xAAAA800A;
    /* Configure PEx pins Output type to push-pull */  
    GPIOE->OTYPER  = 0x00000000;
    /* No pull-up, pull-down for PEx pins */ 
    GPIOE->PUPDR   = 0x00000000;
  
    /* Connect PFx pins to FMC Alternate function */
    GPIOF->AFR[0]  = 0xCCCCCCCC;
    GPIOF->AFR[1]  = 0xCCCCCCCC;
    /* Configure PFx pins in Alternate function mode */   
    GPIOF->MODER   = 0xAA800AAA;
    /* Configure PFx pins speed to 50 MHz */ 
    GPIOF->OSPEEDR = 0xAA800AAA;
    /* Configure PFx pins Output type to push-pull */  
    GPIOF->OTYPER  = 0x00000000;
    /* No pull-up, pull-down for PFx pins */ 
    GPIOF->PUPDR   = 0x00000000;
  
    /* Connect PGx pins to FMC Alternate function */
    GPIOG->AFR[0]  = 0xCCCCCCCC;
    GPIOG->AFR[1]  = 0xCCCCCCCC;
    /* Configure PGx pins in Alternate function mode */ 
    GPIOG->MODER   = 0xAAAAAAAA;
    /* Configure PGx pins speed to 50 MHz */ 
    GPIOG->OSPEEDR = 0xAAAAAAAA;
    /* Configure PGx pins Output type to push-pull */  
    GPIOG->OTYPER  = 0x00000000;
    /* No pull-up, pull-down for PGx pins */ 
    GPIOG->PUPDR   = 0x00000000;
  
  #if defined(STM32F427xx) || defined(STM32F437xx) || defined(STM32F429xx) || defined(STM32F439xx)  
    /* Connect PHx pins to FMC Alternate function */
    GPIOH->AFR[0]  = 0x00C0CC00;
    GPIOH->AFR[1]  = 0xCCCCCCCC;
    /* Configure PHx pins in Alternate function mode */ 
    GPIOH->MODER   = 0xAAAA08A0;
    /* Configure PHx pins speed to 50 MHz */ 
    GPIOH->OSPEEDR = 0xAAAA08A0;
    /* Configure PHx pins Output type to push-pull */  
    GPIOH->OTYPER  = 0x00000000;
    /* No pull-up, pull-down for PHx pins */ 
    GPIOH->PUPDR   = 0x00000000;
    
    /* Connect PIx pins to FMC Alternate function */
    GPIOI->AFR[0]  = 0xCCCCCCCC;
    GPIOI->AFR[1]  = 0x00000CC0;
    /* Configure PIx pins in Alternate function mode */ 
    GPIOI->MODER   = 0x0028AAAA;
    /* Configure PIx pins speed to 50 MHz */ 
    GPIOI->OSPEEDR = 0x0028AAAA;
    /* Configure PIx pins Output type to push-pull */  
    GPIOI->OTYPER  = 0x00000000;
    /* No pull-up, pull-down for PIx pins */ 
    GPIOI->PUPDR   = 0x00000000;
  #endif /* STM32F427xx || STM32F437xx || STM32F429xx || STM32F439xx */
    
  /*-- FMC Configuration -------------------------------------------------------*/
    /* Enable the FMC interface clock */
    RCC->AHB3ENR |= 0x00000001;
    /* Delay after an RCC peripheral clock enabling */
    tmp = READ_BIT(RCC->AHB3ENR, RCC_AHB3ENR_FMCEN);
  
    /* Configure and enable SDRAM bank1 */
  #if defined(STM32F446xx)
    FMC_Bank5_6->SDCR[0] = 0x00001954;
  #else  
    FMC_Bank5_6->SDCR[0] = 0x000019E4;
  #endif /* STM32F446xx */
    FMC_Bank5_6->SDTR[0] = 0x01115351;      
    
    /* SDRAM initialization sequence */
    /* Clock enable command */
    FMC_Bank5_6->SDCMR = 0x00000011; 
    tmpreg = FMC_Bank5_6->SDSR & 0x00000020; 
    while((tmpreg != 0) && (timeout-- > 0))
    {
      tmpreg = FMC_Bank5_6->SDSR & 0x00000020; 
    }
  
    /* Delay */
    for (index = 0; index<1000; index++);
    
    /* PALL command */
    FMC_Bank5_6->SDCMR = 0x00000012;           
    timeout = 0xFFFF;
    while((tmpreg != 0) && (timeout-- > 0))
    {
      tmpreg = FMC_Bank5_6->SDSR & 0x00000020; 
    }
    
    /* Auto refresh command */
  #if defined(STM32F446xx)
    FMC_Bank5_6->SDCMR = 0x000000F3;
  #else  
    FMC_Bank5_6->SDCMR = 0x00000073;
  #endif /* STM32F446xx */
    timeout = 0xFFFF;
    while((tmpreg != 0) && (timeout-- > 0))
    {
      tmpreg = FMC_Bank5_6->SDSR & 0x00000020; 
    }
   
    /* MRD register program */
  #if defined(STM32F446xx)
    FMC_Bank5_6->SDCMR = 0x00044014;
  #else  
    FMC_Bank5_6->SDCMR = 0x00046014;
  #endif /* STM32F446xx */
    timeout = 0xFFFF;
    while((tmpreg != 0) && (timeout-- > 0))
    {
      tmpreg = FMC_Bank5_6->SDSR & 0x00000020; 
    } 
    
    /* Set refresh count */
    tmpreg = FMC_Bank5_6->SDRTR;
  #if defined(STM32F446xx)
    FMC_Bank5_6->SDRTR = (tmpreg | (0x0000050C<<1));
  #else    
    FMC_Bank5_6->SDRTR = (tmpreg | (0x0000027C<<1));
  #endif /* STM32F446xx */
    
    /* Disable write protection */
    tmpreg = FMC_Bank5_6->SDCR[0]; 
    FMC_Bank5_6->SDCR[0] = (tmpreg & 0xFFFFFDFF);
  #endif /* DATA_IN_ExtSDRAM */
  #endif /* STM32F427xx || STM32F437xx || STM32F429xx || STM32F439xx || STM32F446xx */
  
  #if defined(STM32F405xx) || defined(STM32F415xx) || defined(STM32F407xx) || defined(STM32F417xx) ||\
      defined(STM32F427xx) || defined(STM32F437xx) || defined(STM32F429xx) || defined(STM32F439xx)
  
  #if defined(DATA_IN_ExtSRAM)
  /*-- GPIOs Configuration -----------------------------------------------------*/
     /* Enable GPIOD, GPIOE, GPIOF and GPIOG interface clock */
    RCC->AHB1ENR   |= 0x00000078;
    /* Delay after an RCC peripheral clock enabling */
    tmp = READ_BIT(RCC->AHB1ENR, RCC_AHB1ENR_GPIODEN);
    
    /* Connect PDx pins to FMC Alternate function */
    GPIOD->AFR[0]  = 0x00CCC0CC;
    GPIOD->AFR[1]  = 0xCCCCCCCC;
    /* Configure PDx pins in Alternate function mode */  
    GPIOD->MODER   = 0xAAAA0A8A;
    /* Configure PDx pins speed to 100 MHz */  
    GPIOD->OSPEEDR = 0xFFFF0FCF;
    /* Configure PDx pins Output type to push-pull */  
    GPIOD->OTYPER  = 0x00000000;
    /* No pull-up, pull-down for PDx pins */ 
    GPIOD->PUPDR   = 0x00000000;
  
    /* Connect PEx pins to FMC Alternate function */
    GPIOE->AFR[0]  = 0xC00CC0CC;
    GPIOE->AFR[1]  = 0xCCCCCCCC;
    /* Configure PEx pins in Alternate function mode */ 
    GPIOE->MODER   = 0xAAAA828A;
    /* Configure PEx pins speed to 100 MHz */ 
    GPIOE->OSPEEDR = 0xFFFFC3CF;
    /* Configure PEx pins Output type to push-pull */  
    GPIOE->OTYPER  = 0x00000000;
    /* No pull-up, pull-down for PEx pins */ 
    GPIOE->PUPDR   = 0x00000000;
  
    /* Connect PFx pins to FMC Alternate function */
    GPIOF->AFR[0]  = 0x00CCCCCC;
    GPIOF->AFR[1]  = 0xCCCC0000;
    /* Configure PFx pins in Alternate function mode */   
    GPIOF->MODER   = 0xAA000AAA;
    /* Configure PFx pins speed to 100 MHz */ 
    GPIOF->OSPEEDR = 0xFF000FFF;
    /* Configure PFx pins Output type to push-pull */  
    GPIOF->OTYPER  = 0x00000000;
    /* No pull-up, pull-down for PFx pins */ 
    GPIOF->PUPDR   = 0x00000000;
  
    /* Connect PGx pins to FMC Alternate function */
    GPIOG->AFR[0]  = 0x00CCCCCC;
    GPIOG->AFR[1]  = 0x000000C0;
    /* Configure PGx pins in Alternate function mode */ 
    GPIOG->MODER   = 0x00085AAA;
    /* Configure PGx pins speed to 100 MHz */ 
    GPIOG->OSPEEDR = 0x000CAFFF;
    /* Configure PGx pins Output type to push-pull */  
    GPIOG->OTYPER  = 0x00000000;
    /* No pull-up, pull-down for PGx pins */ 
    GPIOG->PUPDR   = 0x00000000;
    
  /*-- FMC/FSMC Configuration --------------------------------------------------*/
    /* Enable the FMC/FSMC interface clock */
    RCC->AHB3ENR         |= 0x00000001;
  
  #if defined(STM32F427xx) || defined(STM32F437xx) || defined(STM32F429xx)|| defined(STM32F439xx)
    /* Delay after an RCC peripheral clock enabling */
    tmp = READ_BIT(RCC->AHB3ENR, RCC_AHB3ENR_FMCEN);
    /* Configure and enable Bank1_SRAM2 */
    FMC_Bank1->BTCR[2]  = 0x00001011;
    FMC_Bank1->BTCR[3]  = 0x00000201;
    FMC_Bank1E->BWTR[2] = 0x0fffffff;
  #endif /* STM32F427xx || STM32F437xx || STM32F429xx || STM32F439xx */ 
  
  #if defined(STM32F405xx) || defined(STM32F415xx) || defined(STM32F407xx)|| defined(STM32F417xx)
    /* Delay after an RCC peripheral clock enabling */
    tmp = READ_BIT(RCC->AHB3ENR, RCC_AHB3ENR_FSMCEN);
    /* Configure and enable Bank1_SRAM2 */
    FSMC_Bank1->BTCR[2]  = 0x00001011;
    FSMC_Bank1->BTCR[3]  = 0x00000201;
    FSMC_Bank1E->BWTR[2] = 0x0FFFFFFF;
  #endif /* STM32F405xx || STM32F415xx || STM32F407xx || STM32F417xx */
  
  #endif /* DATA_IN_ExtSRAM */
  #endif /* STM32F405xx || STM32F415xx || STM32F407xx || STM32F417xx || STM32F427xx || STM32F437xx || STM32F429xx || STM32F439xx */
    (void)(tmp); 
  }
  #endif /* DATA_IN_ExtSRAM || DATA_IN_ExtSDRAM */
  
  /**
    * @brief  Configures the System clock source, PLL Multiplier and Divider factors,
    *               AHB/APBx prescalers and Flash settings
    * @note   This function should be called only once the RCC clock configuration  
    *         is reset to the default reset state (done in SystemInit() function).             
    * @param  None
    * @retval None
    */
  void SetSysClock(void)
  {
    /* 1- Try to start with HSE and external clock */
  #if USE_PLL_HSE_EXTC != 0
    if (SetSysClock_PLL_HSE(1) == 0)
  #endif
    {
      /* 2- If fail try to start with HSE and external xtal */
      #if USE_PLL_HSE_XTAL != 0
      if (SetSysClock_PLL_HSE(0) == 0)
      #endif
      {
        /* 3- If fail start with HSI clock */
        if (SetSysClock_PLL_HSI() == 0)
        {
          while(1)
          {
            // [TODO] Put something here to tell the user that a problem occured...
          }
        }
      }
    }
    
    // Output clock on MCO2 pin(PC9) for debugging purpose
  #if DEBUG_MCO == 1
    HAL_RCC_MCOConfig(RCC_MCO2, RCC_MCO2SOURCE_SYSCLK, RCC_MCODIV_4);
  #endif
  }
  
  #if (USE_PLL_HSE_XTAL != 0) || (USE_PLL_HSE_EXTC != 0)
  /******************************************************************************/
  /*            PLL (clocked by HSE) used as System clock source                */
  /******************************************************************************/
  uint8_t SetSysClock_PLL_HSE(uint8_t bypass)
  {
    RCC_ClkInitTypeDef RCC_ClkInitStruct;
    RCC_OscInitTypeDef RCC_OscInitStruct;
    RCC_PeriphCLKInitTypeDef PeriphClkInitStruct;
    
    /* The voltage scaling allows optimizing the power consumption when the device is 
       clocked below the maximum system frequency, to update the voltage scaling value 
       regarding system frequency refer to product datasheet. */
    __HAL_RCC_PWR_CLK_ENABLE();
    __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
    
    // Enable HSE oscillator and activate PLL with HSE as source
    RCC_OscInitStruct.OscillatorType      = RCC_OSCILLATORTYPE_HSE;
    if (bypass == 0)
    {
      RCC_OscInitStruct.HSEState          = RCC_HSE_ON; // External 8 MHz xtal on OSC_IN/OSC_OUT
    }
    else
    {
      RCC_OscInitStruct.HSEState          = RCC_HSE_BYPASS; // External 8 MHz clock on OSC_IN
    }
    
    RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
    RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
    RCC_OscInitStruct.PLL.PLLM = 8;             // VCO input clock = 1 MHz (8 MHz / 8)
    RCC_OscInitStruct.PLL.PLLN = 360;           // VCO output clock = 360 MHz (1 MHz * 360)
    RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2; // PLLCLK = 180 MHz (360 MHz / 2)
    RCC_OscInitStruct.PLL.PLLQ = 7;             // 
    RCC_OscInitStruct.PLL.PLLR = 2;             // 
    if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
    {
      return 0; // FAIL
    }
  
    // Activate the OverDrive to reach the 180 MHz Frequency
    if (HAL_PWREx_ActivateOverDrive() != HAL_OK)
    {
      return 0; // FAIL
    }
    
    // Select PLLSAI output as USB clock source
    PeriphClkInitStruct.PLLSAI.PLLSAIM = 8;
    PeriphClkInitStruct.PLLSAI.PLLSAIN = 384;
    PeriphClkInitStruct.PLLSAI.PLLSAIP = RCC_PLLSAIP_DIV8;
    PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_CK48;
    PeriphClkInitStruct.Clk48ClockSelection = RCC_CK48CLKSOURCE_PLLSAIP;
    HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct);
    
    // Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2 clocks dividers
    RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2;
    RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
    RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1; // 180 MHz
    RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;  //  45 MHz
    RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;  //  90 MHz
    if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5) != HAL_OK)
    {
      return 0; // FAIL
    }
  
    // Output clock on MCO1 pin(PA8) for debugging purpose
  #if DEBUG_MCO == 1
    if (bypass == 0)
      HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_HSE, RCC_MCODIV_2); // 4 MHz with xtal
    else
      HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_HSE, RCC_MCODIV_1); // 8 MHz with external clock (MCO)
  #endif
  
    return 1; // OK
  }
  #endif
  
  /******************************************************************************/
  /*            PLL (clocked by HSI) used as System clock source                */
  /******************************************************************************/
  uint8_t SetSysClock_PLL_HSI(void)
  {
    RCC_ClkInitTypeDef RCC_ClkInitStruct;
    RCC_OscInitTypeDef RCC_OscInitStruct;
  
    /* The voltage scaling allows optimizing the power consumption when the device is 
       clocked below the maximum system frequency, to update the voltage scaling value 
       regarding system frequency refer to product datasheet. */
    __HAL_RCC_PWR_CLK_ENABLE();
    __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
   
    // Enable HSI oscillator and activate PLL with HSI as source
    RCC_OscInitStruct.OscillatorType      = RCC_OSCILLATORTYPE_HSI | RCC_OSCILLATORTYPE_HSE;
    RCC_OscInitStruct.HSIState            = RCC_HSI_ON;
    RCC_OscInitStruct.HSEState            = RCC_HSE_OFF;
    RCC_OscInitStruct.HSICalibrationValue = 16;
    RCC_OscInitStruct.PLL.PLLState        = RCC_PLL_ON;
    RCC_OscInitStruct.PLL.PLLSource       = RCC_PLLSOURCE_HSI;   
    RCC_OscInitStruct.PLL.PLLM            = 16;            // VCO input clock = 1 MHz (16 MHz / 16)
    RCC_OscInitStruct.PLL.PLLN            = 360;           // VCO output clock = 360 MHz (1 MHz * 360)
    RCC_OscInitStruct.PLL.PLLP            = RCC_PLLP_DIV2; // PLLCLK = 180 MHz (360 MHz / 2)
    RCC_OscInitStruct.PLL.PLLQ            = 7;             //
    RCC_OscInitStruct.PLL.PLLQ            = 6;             //
    if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
    {
      return 0; // FAIL
    }
   
    /* Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2 clocks dividers */
    RCC_ClkInitStruct.ClockType      = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
    RCC_ClkInitStruct.SYSCLKSource   = RCC_SYSCLKSOURCE_PLLCLK; // 180 MHz
    RCC_ClkInitStruct.AHBCLKDivider  = RCC_SYSCLK_DIV1;         // 180 MHz
    RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;           //  45 MHz
    RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;           //  90 MHz
    if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5) != HAL_OK)
    {
      return 0; // FAIL
    }
  
    // Output clock on MCO1 pin(PA8) for debugging purpose
  #if DEBUG_MCO == 1
    HAL_RCC_MCOConfig(RCC_MCO1, RCC_MCO1SOURCE_HSI, RCC_MCODIV_1); // 16 MHz
  #endif
  
    return 1; // OK
  }
  
  /**
    * @}
    */
  
  /**
    * @}
    */
  
  /**
    * @}
    */
  /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
  