/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file    I2C/I2C_WakeUpFromStop2/Src/main.c
  * @author  MCD Application Team
  * @brief   This sample code shows how to use STM32WLxx I2C HAL API to transmit 
  *          and receive a data buffer with a communication process in stop mode 2
  *          based on IT transfer. 
  *          The communication is done using 2 Boards.
  ******************************************************************************
  * @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 */
/* Uncomment this line to use the board as master, if not it is used as slave */
//#define MASTER_BOARD
/* USER CODE END PD */

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

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/
I2C_HandleTypeDef hi2c3;

/* USER CODE BEGIN PV */
/* Buffer used for transmission */
uint8_t aTxBuffer[] = " ****I2C_TwoBoards communication wake up from stop mode 2 based on IT****  ****I2C_TwoBoards communication wake up from stop mode 2 based on IT****  ****I2C_TwoBoards communication wake up from stop mode 2 based on IT**** ";

/* Buffer used for reception */
uint8_t aRxBuffer[RXBUFFERSIZE];
/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_I2C3_Init(void);
/* USER CODE BEGIN PFP */
/* Private function prototypes -----------------------------------------------*/
static uint16_t Buffercmp(uint8_t* pBuffer1, uint8_t* pBuffer2, uint16_t BufferLength);
#ifndef MASTER_BOARD
static void EXTI25_Enable_IT(void);
#endif

/* 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 */

  /* USER CODE END 1 */

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

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

  /* USER CODE BEGIN Init */

  /* USER CODE END Init */

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

  /* USER CODE BEGIN SysInit */

  /* USER CODE END SysInit */

  /* Initialize all configured peripherals */
  MX_GPIO_Init();
  MX_I2C3_Init();
  /* USER CODE BEGIN 2 */
  /* Configure LED2, LED1 and LED3 */
  BSP_LED_Init(LED2);
  BSP_LED_Init(LED3);
  BSP_LED_Init(LED1);

#ifdef MASTER_BOARD

  /* Configure User push-button (B1) */
  BSP_PB_Init(BUTTON_SW1, BUTTON_MODE_GPIO);

  /* Wait for User push-button (B1) press before starting the Communication */
  while (BSP_PB_GetState(BUTTON_SW1) != GPIO_PIN_RESET)
  {
  }

  /* Wait for User push-button (B1) release before starting the Communication */
  while (BSP_PB_GetState(BUTTON_SW1) != GPIO_PIN_SET)
  {
  }

  /* The board sends the message and expects to receive it back */

  /*##- Start the transmission process #####################################*/
  /* While the I2C in reception process, user can transmit data through 
     "aTxBuffer" buffer */
  do
  {
    if(HAL_I2C_Master_Transmit_IT(&hi2c3, (uint16_t)I2C_ADDRESS, (uint8_t*)aTxBuffer, TXBUFFERSIZE)!= HAL_OK)
    {
      /* Error_Handler() function is called when error occurs. */
      Error_Handler();
    }

    /*##- Wait for the end of the transfer #################################*/  
    /*  Before starting a new communication transfer, you need to check the current   
        state of the peripheral; if it's busy you need to wait for the end of current
        transfer before starting a new one.
        For simplicity reasons, this example is just waiting till the end of the 
        transfer, but application may perform other tasks while transfer operation
        is ongoing. */  
    while (HAL_I2C_GetState(&hi2c3) != HAL_I2C_STATE_READY)
    {
    } 

    /* When Acknowledge failure occurs (Slave don't acknowledge it's address)
       Master restarts communication */
  }
  while(HAL_I2C_GetError(&hi2c3) == HAL_I2C_ERROR_AF);

  /* Wait for User push-button (B1) press before starting the Communication */
  while (BSP_PB_GetState(BUTTON_SW1) != GPIO_PIN_RESET)
  {
  }

  /* Wait for User push-button (B1) release before starting the Communication */
  while (BSP_PB_GetState(BUTTON_SW1) != GPIO_PIN_SET)
  {
  }

  /*##- Put I2C peripheral in reception process ###########################*/  
  do
  {
    if(HAL_I2C_Master_Receive_IT(&hi2c3, (uint16_t)I2C_ADDRESS, (uint8_t *)aRxBuffer, RXBUFFERSIZE) != HAL_OK)
    {
      /* Error_Handler() function is called when error occurs. */
      Error_Handler();
    }

    /*##- Wait for the end of the transfer #################################*/  
    /*  Before starting a new communication transfer, you need to check the current   
        state of the peripheral; if it's busy you need to wait for the end of current
        transfer before starting a new one.
        For simplicity reasons, this example is just waiting till the end of the 
        transfer, but application may perform other tasks while transfer operation
        is ongoing. */  
    while (HAL_I2C_GetState(&hi2c3) != HAL_I2C_STATE_READY)
    {
    } 

    /* When Acknowledge failure occurs (Slave don't acknowledge it's address)
       Master restarts communication */
  }
  while(HAL_I2C_GetError(&hi2c3) == HAL_I2C_ERROR_AF);

#else
  /*## Unmask wakeup with Interrupt request from I2C3 #####################*/
  EXTI25_Enable_IT();
  
  /*##- Enable I2C peripheral in wake up from stop mode 2 #################*/  
  HAL_I2CEx_EnableWakeUp(&hi2c3);
  
  /*##- Put I2C peripheral in reception process ###########################*/  
  if(HAL_I2C_Slave_Receive_IT(&hi2c3, (uint8_t *)aRxBuffer, RXBUFFERSIZE) != HAL_OK)
  {
    /* Transfer error in reception process */
    Error_Handler();        
  }
 
  /* enter stop mode 2 */
  /* Turn LED1 on */
  BSP_LED_On(LED1);
  HAL_PWREx_EnterSTOP2Mode(PWR_STOPENTRY_WFI);

  /* ... STOP mode 2 ... */

  /* Wake Up from Stop mode 2 */
  /* Turn LED1 off */
  BSP_LED_Off(LED1);

  /*##- Wait for the end of the transfer ###################################*/  
  /*  Before starting a new communication transfer, you need to check the current   
      state of the peripheral; if it's busy you need to wait for the end of current
      transfer before starting a new one.
      For simplicity reasons, this example is just waiting till the end of the 
      transfer, but application may perform other tasks while transfer operation
      is ongoing. */
  while (HAL_I2C_GetState(&hi2c3) != HAL_I2C_STATE_READY)
  {
  } 
  
  /*##- Start the transmission process #####################################*/  
  /* While the I2C in reception process, user can transmit data through 
     "aTxBuffer" buffer */
  if(HAL_I2C_Slave_Transmit_IT(&hi2c3, (uint8_t*)aTxBuffer, TXBUFFERSIZE)!= HAL_OK)
  {
    /* Transfer error in transmission process */
    Error_Handler();
  }

  /* enter stop mode 2 */
  /* Turn LED1 on */
  BSP_LED_On(LED1);
  HAL_PWREx_EnterSTOP2Mode(PWR_STOPENTRY_WFI);

  /* ... STOP mode 2 ... */  

  /* Wake Up from Stop mode 2 */
  /* Turn LED1 off */
  BSP_LED_Off(LED1);
#endif /* MASTER_BOARD */

  /*##- Wait for the end of the transfer ###################################*/  
  /*  Before starting a new communication transfer, you need to check the current   
      state of the peripheral; if it's busy you need to wait for the end of current
      transfer before starting a new one.
      For simplicity reasons, this example is just waiting till the end of the
      transfer, but application may perform other tasks while transfer operation
      is ongoing. */
  while (HAL_I2C_GetState(&hi2c3) != HAL_I2C_STATE_READY)
  {
  } 
  
  /*##- Compare the sent and received buffers ##############################*/
  if(Buffercmp((uint8_t*)aTxBuffer,(uint8_t*)aRxBuffer,RXBUFFERSIZE))
  {
    /* Processing Error */
    Error_Handler();      
  }
  /* USER CODE END 2 */

  /* Infinite loop */
  /* USER CODE BEGIN WHILE */
  while (1)
  {
    /* 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_SCALE2);

  /** Initializes the CPU, AHB and APB buses clocks
  */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
  RCC_OscInitStruct.HSIState = RCC_HSI_ON;
  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;
  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_HSI;
  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_0) != HAL_OK)
  {
    Error_Handler();
  }
}

/**
  * @brief I2C3 Initialization Function
  * @param None
  * @retval None
  */
static void MX_I2C3_Init(void)
{

  /* USER CODE BEGIN I2C3_Init 0 */

  /* USER CODE END I2C3_Init 0 */

  /* USER CODE BEGIN I2C3_Init 1 */

  /* USER CODE END I2C3_Init 1 */
  hi2c3.Instance = I2C3;
  hi2c3.Init.Timing = 0x0020098E;
  hi2c3.Init.OwnAddress1 = 202;
  hi2c3.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
  hi2c3.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE;
  hi2c3.Init.OwnAddress2 = 0;
  hi2c3.Init.OwnAddress2Masks = I2C_OA2_NOMASK;
  hi2c3.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE;
  hi2c3.Init.NoStretchMode = I2C_NOSTRETCH_DISABLE;
  if (HAL_I2C_Init(&hi2c3) != HAL_OK)
  {
    Error_Handler();
  }
  /** Configure Analogue filter
  */
  if (HAL_I2CEx_ConfigAnalogFilter(&hi2c3, I2C_ANALOGFILTER_ENABLE) != HAL_OK)
  {
    Error_Handler();
  }
  /** Configure Digital filter
  */
  if (HAL_I2CEx_ConfigDigitalFilter(&hi2c3, 0) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN I2C3_Init 2 */

  /* USER CODE END I2C3_Init 2 */

}

/**
  * @brief GPIO Initialization Function
  * @param None
  * @retval None
  */
static void MX_GPIO_Init(void)
{

  /* GPIO Ports Clock Enable */
  __HAL_RCC_GPIOB_CLK_ENABLE();

}

/* USER CODE BEGIN 4 */
/**
  * @brief  Tx Transfer completed callback.
  * @param  I2cHandle: I2C handle. 
  * @note   This example shows a simple way to report end of IT Tx transfer, and 
  *         you can add your own implementation. 
  * @retval None
  */
#ifdef MASTER_BOARD
void HAL_I2C_MasterTxCpltCallback(I2C_HandleTypeDef *I2cHandle)
{
  /* Toggle LED2: Transfer in transmission process is correct */
  BSP_LED_Toggle(LED2);
}
#else
void HAL_I2C_SlaveTxCpltCallback(I2C_HandleTypeDef *I2cHandle)
{
  /* Restore config: clock, GPIO... */
  SystemClock_Config();

  /* Restore GPIO configuration */
  BSP_LED_Init(LED2);
  BSP_LED_Init(LED1);

  /* Wake Up from Stop Mode 2 */
  /* Turn LED1 off */
  BSP_LED_Off(LED1);
  /* Turn off LED2: Transfer in transmission process is correct */
  BSP_LED_Off(LED2);
}
#endif /* MASTER_BOARD */

/**
  * @brief  Rx Transfer completed callback.
  * @param  I2cHandle: I2C handle
  * @note   This example shows a simple way to report end of IT Rx transfer, and 
  *         you can add your own implementation.
  * @retval None
  */
#ifdef MASTER_BOARD
void HAL_I2C_MasterRxCpltCallback(I2C_HandleTypeDef *I2cHandle)
{
  /* Toggle LED2: Transfer in reception process is correct */
  BSP_LED_Toggle(LED2);
}
#else
void HAL_I2C_SlaveRxCpltCallback(I2C_HandleTypeDef *I2cHandle)
{
  /* Restore config: clock, GPIO... */
  SystemClock_Config();

  /* Restore GPIO configuration */
  BSP_LED_Init(LED2);
  BSP_LED_Init(LED1);

  /* Wake Up from Stop Mode 2 */
  /* Turn LED1 off */
  BSP_LED_Off(LED1);

  /* Turn On LED2: Transfer in reception process is correct */
  BSP_LED_On(LED2);
}
#endif /* MASTER_BOARD */

/**
  * @brief  I2C error callbacks.
  * @param  I2cHandle: I2C handle
  * @note   This example shows a simple way to report transfer error, and you can
  *         add your own implementation.
  * @retval None
  */
#ifdef MASTER_BOARD
void HAL_I2C_ErrorCallback(I2C_HandleTypeDef *I2cHandle)
{
  /* Turn LED3 on: Transfer error in reception/transmission process */
  BSP_LED_On(LED3); 
}
#else
void HAL_I2C_ErrorCallback(I2C_HandleTypeDef *I2cHandle)
{
  /* Restore config: clock, GPIO... */
  SystemClock_Config();

  /** Error_Handler() function is called when error occurs.
    * 1- When Slave doesn't acknowledge its address, Master restarts communication.
    * 2- When Master doesn't acknowledge the last data transferred, Slave doesn't care in this example.
    */
  if (HAL_I2C_GetError(I2cHandle) != HAL_I2C_ERROR_AF)
  {
    /* Restore GPIO configuration */
    BSP_LED_Init(LED2);
    BSP_LED_Init(LED3);

    /* Turn Off LED2 */
    BSP_LED_Off(LED2);

    /* Turn On LED3 */
    BSP_LED_On(LED3);
  }
}

#endif /* MASTER_BOARD */
#ifndef MASTER_BOARD
static void EXTI25_Enable_IT(void)
{
  EXTI_HandleTypeDef hexti;
  EXTI_ConfigTypeDef exticonfig;  
  exticonfig.Line = EXTI_LINE_25;
  exticonfig.Mode = EXTI_MODE_INTERRUPT;  
  HAL_EXTI_SetConfigLine(&hexti,&exticonfig);
}
#endif
/**
  * @brief  Compares two buffers.
  * @param  pBuffer1, pBuffer2: buffers to be compared.
  * @param  BufferLength: buffer's length
  * @retval 0  : pBuffer1 identical to pBuffer2
  *         >0 : pBuffer1 differs from pBuffer2
  */
static uint16_t Buffercmp(uint8_t* pBuffer1, uint8_t* pBuffer2, uint16_t BufferLength)
{
  while (BufferLength--)
  {
    if ((*pBuffer1) != *pBuffer2)
    {
      return BufferLength;
    }
    pBuffer1++;
    pBuffer2++;
  }

  return 0;
}
/* 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 */
  /* Turn LED3 on */
  BSP_LED_On(LED3);
  while(1)
  {
  }
  /* 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) */
  Error_Handler();
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
