/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file    UART/UART_HyperTerminal_TxPolling_RxIT/Src/main.c
  * @author  MCD Application Team
  * @brief   This sample code shows how to use UART HAL and LL APIs to transmit
  *          data in polling mode while receiving data in Interrupt mode, by mixing 
  *          use of LL and HAL APIs;
  *          HAL driver is used to perform UART configuration, 
  *          then TX transfer procedure is based on HAL APIs use (polling)
  *               RX transfer procedure is based on LL APIs use (IT)
  ******************************************************************************
  * @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 */

/* USER CODE END PD */

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

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/
UART_HandleTypeDef huart2;

/* USER CODE BEGIN PV */

/* Buffer used for transmission */
uint8_t aTxStartMessage[] = "\n\r ****UART-Hyperterminal TXRX communication (TX based on HAL polling API, RX based on IT LL API) ****\n\r Enter characters using keyboard ...\n\r";
uint8_t ubSizeToSend = sizeof(aTxStartMessage);

/* Buffer used for reception */
uint8_t aRXBufferA[RX_BUFFER_SIZE];
uint8_t aRXBufferB[RX_BUFFER_SIZE];
__IO uint32_t uwNbReceivedChars = 0;
__IO uint32_t uwBufferReadyIndication = 0;
uint8_t *pBufferReadyForUser;
uint8_t *pBufferReadyForReception;

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_USART2_UART_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 */
  /* Configure leds */
  BSP_LED_Init(LED2);
  BSP_LED_Init(LED1);
  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_GPIO_Init();
  MX_USART2_UART_Init();
  /* USER CODE BEGIN 2 */

  /*## Configure UART peripheral for reception process (using LL) ##########*/  
  /* Initializes Buffer swap mechanism :
     2 physical buffers aRXBufferA and aRXBufferB (RX_BUFFER_SIZE length)
     Any data received will be stored in active buffer : the number max of 
     data received is RX_BUFFER_SIZE */
  pBufferReadyForReception = aRXBufferA;
  pBufferReadyForUser      = aRXBufferB;
  uwNbReceivedChars = 0;
  uwBufferReadyIndication = 0;
  /* Enable RXNE and Error interrupts */  
  LL_USART_EnableIT_RXNE(USART2);
  LL_USART_EnableIT_ERROR(USART2);

  /*## Start the transmission process (using HAL Polling mode) #############*/  
  /* In main loop, Tx buffer is sent every 0.5 sec. 
     As soon as RX buffer is detected as full, received bytes are echoed on TX line to PC com port */
  /* USER CODE END 2 */

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

    /* USART IRQ handler is not anymore routed to HAL_UART_IRQHandler() function 
       and is now based on LL API functions use. 
       Therefore, use of HAL IT based services is no more possible : use TX HAL polling services */
    if(HAL_UART_Transmit(&huart2, (uint8_t*)aTxStartMessage, ubSizeToSend, 1000)!= HAL_OK)
    {
      /* Transfer error in transmission process */
      Error_Handler();
    }

    /* Checks if Buffer full indication has been set */
    if (uwBufferReadyIndication != 0)
    {
      /* Reset indication */
      uwBufferReadyIndication = 0;

      /* USART IRQ handler is not anymore routed to HAL_UART_IRQHandler() function 
         and is now based on LL API functions use. 
         Therefore, use of HAL IT based services is no more possible : use TX HAL polling services */
      if(HAL_UART_Transmit(&huart2, (uint8_t*)pBufferReadyForUser, RX_BUFFER_SIZE, 1000)!= HAL_OK)
      {
        /* Transfer error in transmission process */
        Error_Handler();
      }

      /* Toggle LED2 */
      BSP_LED_Toggle(LED2);
    }

    /* Manage temporisation between TX buffer sendings */
    HAL_Delay(500);

    /* 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_8;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_MSI;
  RCC_OscInitStruct.PLL.PLLM = RCC_PLLM_DIV4;
  RCC_OscInitStruct.PLL.PLLN = 24;
  RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
  RCC_OscInitStruct.PLL.PLLR = RCC_PLLR_DIV2;
  RCC_OscInitStruct.PLL.PLLQ = RCC_PLLQ_DIV2;
  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_PLLCLK;
  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 USART2 Initialization Function
  * @param None
  * @retval None
  */
static void MX_USART2_UART_Init(void)
{

  /* USER CODE BEGIN USART2_Init 0 */

  /* USER CODE END USART2_Init 0 */

  /* USER CODE BEGIN USART2_Init 1 */

  /* USER CODE END USART2_Init 1 */
  huart2.Instance = USART2;
  huart2.Init.BaudRate = 9600;
  huart2.Init.WordLength = UART_WORDLENGTH_8B;
  huart2.Init.StopBits = UART_STOPBITS_1;
  huart2.Init.Parity = UART_PARITY_ODD;
  huart2.Init.Mode = UART_MODE_TX_RX;
  huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE;
  huart2.Init.OverSampling = UART_OVERSAMPLING_16;
  huart2.Init.OneBitSampling = UART_ONE_BIT_SAMPLE_DISABLE;
  huart2.Init.ClockPrescaler = UART_PRESCALER_DIV1;
  huart2.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;
  if (HAL_UART_Init(&huart2) != HAL_OK)
  {
    Error_Handler();
  }
  if (HAL_UARTEx_SetTxFifoThreshold(&huart2, UART_TXFIFO_THRESHOLD_1_8) != HAL_OK)
  {
    Error_Handler();
  }
  if (HAL_UARTEx_SetRxFifoThreshold(&huart2, UART_RXFIFO_THRESHOLD_1_8) != HAL_OK)
  {
    Error_Handler();
  }
  if (HAL_UARTEx_DisableFifoMode(&huart2) != HAL_OK)
  {
    Error_Handler();
  }
  /* USER CODE BEGIN USART2_Init 2 */

  /* USER CODE END USART2_Init 2 */

}

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

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

}

/* USER CODE BEGIN 4 */

/**
  * @brief  Rx Transfer completed callback
  * @note   This example shows a simple way to report end of IT Rx transfer, and 
  *         you can add your own implementation.
  * @retval None
  */
void UART_CharReception_Callback(void)
{
uint8_t *ptemp;

  /* Read Received character. RXNE flag is cleared by reading of RDR register */
  pBufferReadyForReception[uwNbReceivedChars++] = LL_USART_ReceiveData8(USART2);

  /* Checks if Buffer full indication has to be set */
  if (uwNbReceivedChars >= RX_BUFFER_SIZE)
  {
    /* Set Buffer swap indication */
    uwBufferReadyIndication = 1;

    /* Swap buffers for next bytes to be received */
    ptemp = pBufferReadyForUser;
    pBufferReadyForUser = pBufferReadyForReception;
    pBufferReadyForReception = ptemp;
    uwNbReceivedChars = 0;
  }
}

/**
  * @brief  UART error callbacks
  * @note   This example shows a simple way to report transfer error, and you can
  *         add your own implementation.
  * @retval None
  */
void UART_Error_Callback(void)
{
  __IO uint32_t isr_reg;

  /* Disable USARTx_IRQn */
  NVIC_DisableIRQ(USART2_IRQn);
  
  /* Error handling example :
    - Read USART ISR register to identify flag that leads to IT raising
    - Perform corresponding error handling treatment according to flag
  */
  isr_reg = LL_USART_ReadReg(USART2, ISR);
  if (isr_reg & LL_USART_ISR_NE)
  {
    /* Turn LED3 on: Transfer error in reception/transmission process */
    BSP_LED_On(LED3);
  }
  else
  {
    /* Turn LED3 on: Transfer error in reception/transmission process */
    BSP_LED_On(LED3);
  }
}

/* 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 */
  /* Toggle LED3 for error */
  while(1)
  {
    BSP_LED_Toggle(LED3);
    HAL_Delay(1000);
  }
  /* 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,
     tex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
  /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */
