/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file    RNG/RNG_MultiRNG_IT/Src/main.c
  * @author  MCD Application Team
  * @brief   This sample code shows how to use the RNG HAL API
  *          to generate 32-bit long random numbers in interruption mode.
  ******************************************************************************
  * @attention
  *
  * Copyright (c) 2020 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.
  *
  ******************************************************************************
  */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */

/* USER CODE END Includes */

/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */
/* Length of array of 32-bit long random numbers to be filled up */
#define N  8
/* USER CODE END PD */

/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/
RNG_HandleTypeDef hrng;

/* USER CODE BEGIN PV */

/* Used for storing 8 Random 32bit Numbers */
__IO uint32_t aRandom32bit[N];

/* Used to counter the random numbers */
uint32_t counter = 0;

__IO uint8_t    ubUserButtonClickEvent = RESET;  /* Event detection: Set after User Button interrupt */
__IO uint32_t    RNGStatus = 0;

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_RNG_Init(void);
/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

/**
  * @brief  The application entry point.
  * @retval int
  */
int main(void)
{
  /* USER CODE BEGIN 1 */

  /* STM32WLxx HAL library initialization:
       - Configure the Flash prefetch
       - Systick timer is configured by default as source of time base, but user 
         can eventually implement his proper time base source (a general purpose 
         timer for example or other time source), keeping in mind that Time base 
         duration should be kept 1ms since PPP_TIMEOUT_VALUEs are defined and 
         handled in milliseconds basis.
       - Set NVIC Group Priority to 4
       - Low Level Initialization
     */
  /* USER CODE END 1 */

  /* MCU Configuration--------------------------------------------------------*/

  /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
  HAL_Init();

  /* USER CODE BEGIN Init */

  /* Initialize LED Error on board */
  BSP_LED_Init(LED3);

  /* USER CODE END Init */

  /* Configure the system clock */
  SystemClock_Config();

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_RNG_Init();
  /* USER CODE BEGIN 2 */

  /* Configure User push-button (B1) in Interrupt mode */
  BSP_PB_Init(BUTTON_SW1, BUTTON_MODE_EXTI);

  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {

    /* Wait for event on push button to perform following actions */
    while ((ubUserButtonClickEvent) == RESET)
    {
      __NOP();
    }
    /* Reset variable for next loop iteration */
    ubUserButtonClickEvent = RESET;

    /* Generate eight 32-bit long random numbers */
    counter = 0;
    /* Enable RNG peripheral IT */
    if (HAL_RNG_GenerateRandomNumber_IT(&hrng) != HAL_OK)
    {
      /* RNG peripheral start-up error */
      Error_Handler();
    }

    /* HAL_RNG_ReadyCallback() API retrieves the random numbers,
      stores them in aRandom32bit[] array and
      accordingly increases counter variable. */
    while (counter != N);
    /* USER CODE END WHILE */

    /* USER CODE BEGIN 3 */


  }
  /* USER CODE END 3 */
}

/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC_OscInitTypeDef RCC_OscInitStruct = {0};
  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  /** Configure the main internal regulator output voltage
  */
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);

  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_MSI;
  RCC_OscInitStruct.MSIState = RCC_MSI_ON;
  RCC_OscInitStruct.MSICalibrationValue = RCC_MSICALIBRATION_DEFAULT;
  RCC_OscInitStruct.MSIClockRange = RCC_MSIRANGE_11;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
  {
    Error_Handler();
  }
  /** Configure the SYSCLKSource, HCLK, PCLK1 and PCLK2 clocks dividers
  */
  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK3|RCC_CLOCKTYPE_HCLK
                              |RCC_CLOCKTYPE_SYSCLK|RCC_CLOCKTYPE_PCLK1
                              |RCC_CLOCKTYPE_PCLK2;
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_MSI;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
  RCC_ClkInitStruct.AHBCLK3Divider = RCC_SYSCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
  {
    Error_Handler();
  }
}

/**
  * @brief RNG Initialization Function
  * @param None
  * @retval None
  */
static void MX_RNG_Init(void)
{

  /* USER CODE BEGIN RNG_Init 0 */

  /* USER CODE END RNG_Init 0 */

  /* USER CODE BEGIN RNG_Init 1 */

  /* USER CODE END RNG_Init 1 */
  hrng.Instance = RNG;
  hrng.Init.ClockErrorDetection = RNG_CED_ENABLE;
  if (HAL_RNG_Init(&hrng) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN RNG_Init 2 */

  /* USER CODE END RNG_Init 2 */

}

/* USER CODE BEGIN 4 */
/**
  * @brief EXTI line detection callbacks
  * @param GPIO_Pin: Specifies the pins connected EXTI line
  * @retval None
  */
void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin)
{
  if (GPIO_Pin == BUTTON_SW1_PIN)
  {
    /* Set variable to report push button event to main program */
    ubUserButtonClickEvent = SET;
    RNGStatus = 1;
  }
}


/**
  * @brief  Data Ready callback in non-blocking mode.
  * @param  hrng: pointer to RNG_HandleTypeDef structure.
  * @retval None
  */
void HAL_RNG_ReadyDataCallback(RNG_HandleTypeDef *hrng, uint32_t random32bit)
{

  /* Straight random number retrieval */
  aRandom32bit[counter] = random32bit;
  counter++;

  /* HAL_RNG_IRQHandler() disables IT at each interruption,
     so, need to re-enable IT in callback to get several random numbers in a row */
  if (counter != N)
  {
    HAL_RNG_GenerateRandomNumber_IT(hrng);
  }

}

/**
  * @brief  RNG error callback.
  * @param  hrng: pointer to RNG_HandleTypeDef structure.
  * @retval None
  */
void HAL_RNG_ErrorCallback(RNG_HandleTypeDef *hrng)
{
  Error_Handler();
}
/* USER CODE END 4 */

/**
  * @brief  This function is executed in case of error occurrence.
  * @retval None
  */
void Error_Handler(void)
{
  /* USER CODE BEGIN Error_Handler_Debug */
  /* User can add his own implementation to report the HAL error return state */
  RNGStatus = 0XE;
  while (1)
  {
    /* Toggle LED3 */
    BSP_LED_Toggle(LED3);
    HAL_Delay(500);
  }
  /* USER CODE END Error_Handler_Debug */
}

#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 CODE BEGIN 6 */
  /* 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) */
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
