/**
  ******************************************************************************
  * @file    Examples_MIX/CRC/CRC_CalculateAndCheck/Src/main.c
  * @author  MCD Application Team
  * @brief   This sample code shows how to use the STM32F2xx CRC HAL API
  *          to compute a CRC code of a given buffer of data words (32-bit).
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2017 STMicroelectronics.
  * All rights reserved.
  *
  * This software is licensed under terms that can be found in the LICENSE file
  * in the root directory of this software component.
  * If no LICENSE file comes with this software, it is provided AS-IS.
  *
  ******************************************************************************
  */

/* Includes ------------------------------------------------------------------*/
#include "main.h"

#include "stm32f2xx_ll_crc.h"


/** @addtogroup STM32F2xx_HAL_Examples
  * @{
  */

/** @addtogroup CRC_CalculateAndCheck
  * @{
  */

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

/* Private define ------------------------------------------------------------*/
#define BUFFER_SIZE    9

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

/* Private variables ---------------------------------------------------------*/
/* CRC handler declaration */
CRC_HandleTypeDef   CrcHandle;

/* Used for storing CRC Value */
__IO uint32_t uwCRCValue = 0;

static const uint32_t aDataBuffer[BUFFER_SIZE] =
{
  0x00001021, 0x20423063, 0x408450a5,
  0x60c670e7, 0x9129a14a, 0xb16bc18c,
  0xd1ade1ce, 0xf1ef1231, 0x32732252
};

/* Expected CRC Value */
uint32_t uwExpectedCRCValue = 0xFF813A5C;


/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void Error_Handler(void);

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

/**
  * @brief  Main program
  * @param  None
  * @retval None
  */
int main(void)
{
  register volatile uint32_t index = 0;

  /* STM32F2xx HAL library initialization:
       - Configure the Flash prefetch, instruction and Data caches
       - Configure the Systick to generate an interrupt each 1 msec
       - Set NVIC Group Priority to 4
       - Global MSP (MCU Support Package) initialization
     */
  HAL_Init();
  
  /* Configure the system clock to 120 MHz */
  SystemClock_Config();

  /* Configure LED1 and LED3 */
  BSP_LED_Init(LED1);
  BSP_LED_Init(LED3);

  /*##-1- Configure the CRC peripheral #######################################*/
  CrcHandle.Instance = CRC;

  if (HAL_CRC_Init(&CrcHandle) != HAL_OK)
  {
    /* Initialization Error */
    Error_Handler();
  }

  /*##-2- Compute the CRC of "aDataBuffer" ###################################*/
  uwCRCValue = HAL_CRC_Calculate(&CrcHandle, (uint32_t *)&aDataBuffer, BUFFER_SIZE);

  /*##-3- Compare the CRC value to the Expected one ##########################*/
  if (uwCRCValue != uwExpectedCRCValue)
  {
    /* Wrong CRC value: enter Error_Handler */
    Error_Handler();
  }
  else
  {
    /*##-4- Compute the CRC of "aDataBuffer" ###################################*/
    /* Reset the CRC calculation unit */
    LL_CRC_ResetCRCCalculationUnit(CRC);

    /* Compute the CRC of Data Buffer array*/
    for (index = 0; index < BUFFER_SIZE; index++)
    {
      LL_CRC_FeedData32(CRC, aDataBuffer[index]);
    }
    uwCRCValue = LL_CRC_ReadData32(CRC);

    /*##-5- Compare the CRC value to the Expected one ##########################*/
    if (uwCRCValue != uwExpectedCRCValue)
    {
      /* Wrong CRC value: enter Error_Handler */
      Error_Handler();
    }
    else
    {
      /* Right CRC value: Turn LED1 on */
      BSP_LED_On(LED1);
    }
  }

  /* Infinite loop */
  while (1)
  {
  }
}

/**
  * @brief  System Clock Configuration
  *         The system Clock is configured as follow : 
  *            System Clock source            = PLL (HSE)
  *            SYSCLK(Hz)                     = 120000000
  *            HCLK(Hz)                       = 120000000
  *            AHB Prescaler                  = 1
  *            APB1 Prescaler                 = 4
  *            APB2 Prescaler                 = 2
  *            HSE Frequency(Hz)              = 8000000
  *            PLL_M                          = 8
  *            PLL_N                          = 240
  *            PLL_P                          = 2
  *            PLL_Q                          = 5
  *            VDD(V)                         = 3.3
  *            Flash Latency(WS)              = 3
  * @param  None
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_ClkInitTypeDef RCC_ClkInitStruct;
  RCC_OscInitTypeDef RCC_OscInitStruct;

  /* Enable HSE Oscillator and activate PLL with HSE as source */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_BYPASS;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLM = 8;
  RCC_OscInitStruct.PLL.PLLN = 240;
  RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
  RCC_OscInitStruct.PLL.PLLQ = 5;
  HAL_RCC_OscConfig(&RCC_OscInitStruct);
  
  /* 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;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;
  HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_3);
}
/**
  * @brief  This function is executed in case of error occurrence.
  * @param  None
  * @retval None
  */
static void Error_Handler(void)
{
  /* Turn LED3 on */
  BSP_LED_On(LED3);
  while (1)
  {
  }

}

#ifdef  USE_FULL_ASSERT
/**
  * @brief  Reports the name of the source file and the source line number
  *         where the assert_param error has occurred.
  * @param  file: pointer to the source file name
  * @param  line: assert_param error line source number
  * @retval None
  */
void assert_failed(uint8_t *file, uint32_t line)
{
  /* User can add his own implementation to report the file name and line number,
     ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */

  /* Infinite loop */
  while (1)
  {
  }
}
#endif

/**
  * @}
  */

/**
  * @}
  */