/* USER CODE BEGIN Header */
/**
  ******************************************************************************
  * @file    Examples_LL/SPI/SPI_TwoBoards_FullDuplex_IT_Slave_Init/Src/main.c
  * @author  MCD Application Team
  * @brief   This example describes how to send/receive bytes over SPI IP using
  *          the STM32WLxx SPI LL API.
  *          Peripheral initialization done using LL unitary services functions.
  ******************************************************************************
  * @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 ---------------------------------------------------------*/

/* USER CODE BEGIN PV */
__IO uint8_t ubButtonPress = 0;

/* Buffer used for transmission */
uint8_t aTxBuffer[] = "**** SPI_TwoBoards_FullDuplex_IT communication **** SPI_TwoBoards_FullDuplex_IT communication **** SPI_TwoBoards_FullDuplex_IT communication ****";
uint8_t ubNbDataToTransmit = sizeof(aTxBuffer);
__IO uint8_t ubTransmitIndex = 0;

/* Buffer used for reception */
uint8_t aRxBuffer[sizeof(aTxBuffer)];
uint8_t ubNbDataToReceive = sizeof(aTxBuffer);
__IO uint8_t ubReceiveIndex = 0;

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_SPI1_Init(void);
/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */
void     Activate_SPI(void);
void     LED_On(void);
void     LED_Blinking(uint32_t Period);

void     WaitAndCheckEndOfTransfer(void);
uint8_t  Buffercmp8(uint8_t *pBuffer1, uint8_t *pBuffer2, uint8_t BufferLength);
/* 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. */

  /* System interrupt init*/
  NVIC_SetPriorityGrouping(NVIC_PRIORITYGROUP_4);

  /* 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_SPI1_Init();
  /* USER CODE BEGIN 2 */

  /* Configure the SPI1 FIFO Threshold */
  LL_SPI_SetRxFIFOThreshold(SPI1, LL_SPI_RX_FIFO_TH_QUARTER);

  /* Configure SPI1 transfer interrupts */
  /* Enable TXE   Interrupt */
  LL_SPI_EnableIT_TXE(SPI1);
  /* Enable RXNE  Interrupt */
  LL_SPI_EnableIT_RXNE(SPI1);
  /* Enable SPI1 Error Interrupt */
  LL_SPI_EnableIT_ERR(SPI1);

  /* Enable the SPI1 peripheral */
  Activate_SPI();

  /* Wait for the end of the transfer and check received data */
  /* LED blinking FAST during waiting time */
  WaitAndCheckEndOfTransfer();

  /* 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)
{
  LL_FLASH_SetLatency(LL_FLASH_LATENCY_2);
  while(LL_FLASH_GetLatency() != LL_FLASH_LATENCY_2)
  {
  }

  LL_PWR_SetRegulVoltageScaling(LL_PWR_REGU_VOLTAGE_SCALE1);
  LL_RCC_MSI_Enable();

   /* Wait till MSI is ready */
  while(LL_RCC_MSI_IsReady() != 1)
  {
  }

  LL_RCC_MSI_EnableRangeSelection();
  LL_RCC_MSI_SetRange(LL_RCC_MSIRANGE_11);
  LL_RCC_MSI_SetCalibTrimming(0);
  LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_MSI);

   /* Wait till System clock is ready */
  while(LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_MSI)
  {
  }

  LL_RCC_SetAHBPrescaler(LL_RCC_SYSCLK_DIV_1);
  LL_RCC_SetAHB3Prescaler(LL_RCC_SYSCLK_DIV_1);
  LL_RCC_SetAPB1Prescaler(LL_RCC_APB1_DIV_1);
  LL_RCC_SetAPB2Prescaler(LL_RCC_APB2_DIV_1);

  LL_Init1msTick(48000000);

  /* Update CMSIS variable (which can be updated also through SystemCoreClockUpdate function) */
  LL_SetSystemCoreClock(48000000);
}

/**
  * @brief SPI1 Initialization Function
  * @param None
  * @retval None
  */
static void MX_SPI1_Init(void)
{

  /* USER CODE BEGIN SPI1_Init 0 */

  /* USER CODE END SPI1_Init 0 */

  LL_SPI_InitTypeDef SPI_InitStruct = {0};

  LL_GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* Peripheral clock enable */
  LL_APB2_GRP1_EnableClock(LL_APB2_GRP1_PERIPH_SPI1);

  LL_AHB2_GRP1_EnableClock(LL_AHB2_GRP1_PERIPH_GPIOA);
  /**SPI1 GPIO Configuration
  PA6   ------> SPI1_MISO
  PA7   ------> SPI1_MOSI
  PA5   ------> SPI1_SCK
  */
  GPIO_InitStruct.Pin = LL_GPIO_PIN_6;
  GPIO_InitStruct.Mode = LL_GPIO_MODE_ALTERNATE;
  GPIO_InitStruct.Speed = LL_GPIO_SPEED_FREQ_HIGH;
  GPIO_InitStruct.OutputType = LL_GPIO_OUTPUT_PUSHPULL;
  GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
  GPIO_InitStruct.Alternate = LL_GPIO_AF_5;
  LL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  GPIO_InitStruct.Pin = LL_GPIO_PIN_7|LL_GPIO_PIN_5;
  GPIO_InitStruct.Mode = LL_GPIO_MODE_ALTERNATE;
  GPIO_InitStruct.Speed = LL_GPIO_SPEED_FREQ_HIGH;
  GPIO_InitStruct.OutputType = LL_GPIO_OUTPUT_PUSHPULL;
  GPIO_InitStruct.Pull = LL_GPIO_PULL_DOWN;
  GPIO_InitStruct.Alternate = LL_GPIO_AF_5;
  LL_GPIO_Init(GPIOA, &GPIO_InitStruct);

  /* SPI1 interrupt Init */
  NVIC_SetPriority(SPI1_IRQn, NVIC_EncodePriority(NVIC_GetPriorityGrouping(),0, 0));
  NVIC_EnableIRQ(SPI1_IRQn);

  /* USER CODE BEGIN SPI1_Init 1 */

  /* USER CODE END SPI1_Init 1 */
  /* SPI1 parameter configuration*/
  SPI_InitStruct.TransferDirection = LL_SPI_FULL_DUPLEX;
  SPI_InitStruct.Mode = LL_SPI_MODE_SLAVE;
  SPI_InitStruct.DataWidth = LL_SPI_DATAWIDTH_8BIT;
  SPI_InitStruct.ClockPolarity = LL_SPI_POLARITY_HIGH;
  SPI_InitStruct.ClockPhase = LL_SPI_PHASE_2EDGE;
  SPI_InitStruct.NSS = LL_SPI_NSS_SOFT;
  SPI_InitStruct.BitOrder = LL_SPI_MSB_FIRST;
  SPI_InitStruct.CRCCalculation = LL_SPI_CRCCALCULATION_DISABLE;
  SPI_InitStruct.CRCPoly = 7;
  LL_SPI_Init(SPI1, &SPI_InitStruct);
  LL_SPI_SetStandard(SPI1, LL_SPI_PROTOCOL_MOTOROLA);
  LL_SPI_DisableNSSPulseMgt(SPI1);
  /* USER CODE BEGIN SPI1_Init 2 */

  /* USER CODE END SPI1_Init 2 */

}

/**
  * @brief GPIO Initialization Function
  * @param None
  * @retval None
  */
static void MX_GPIO_Init(void)
{
  LL_EXTI_InitTypeDef EXTI_InitStruct = {0};
  LL_GPIO_InitTypeDef GPIO_InitStruct = {0};

  /* GPIO Ports Clock Enable */
  LL_AHB2_GRP1_EnableClock(LL_AHB2_GRP1_PERIPH_GPIOB);
  LL_AHB2_GRP1_EnableClock(LL_AHB2_GRP1_PERIPH_GPIOA);

  /**/
  LL_GPIO_ResetOutputPin(LED2_GPIO_Port, LED2_Pin);

  /**/
  GPIO_InitStruct.Pin = LED2_Pin;
  GPIO_InitStruct.Mode = LL_GPIO_MODE_OUTPUT;
  GPIO_InitStruct.Speed = LL_GPIO_SPEED_FREQ_LOW;
  GPIO_InitStruct.OutputType = LL_GPIO_OUTPUT_PUSHPULL;
  GPIO_InitStruct.Pull = LL_GPIO_PULL_NO;
  LL_GPIO_Init(LED2_GPIO_Port, &GPIO_InitStruct);

  /**/
  LL_SYSCFG_SetEXTISource(LL_SYSCFG_EXTI_PORTA, LL_SYSCFG_EXTI_LINE0);

  /**/
  EXTI_InitStruct.Line_0_31 = LL_EXTI_LINE_0;
  EXTI_InitStruct.Line_32_63 = LL_EXTI_LINE_NONE;
  EXTI_InitStruct.LineCommand = ENABLE;
  EXTI_InitStruct.Mode = LL_EXTI_MODE_IT;
  EXTI_InitStruct.Trigger = LL_EXTI_TRIGGER_FALLING;
  LL_EXTI_Init(&EXTI_InitStruct);

  /**/
  LL_GPIO_SetPinPull(USER_BUTTON_GPIO_Port, USER_BUTTON_Pin, LL_GPIO_PULL_UP);

  /**/
  LL_GPIO_SetPinMode(USER_BUTTON_GPIO_Port, USER_BUTTON_Pin, LL_GPIO_MODE_INPUT);

  /* EXTI interrupt init*/
  NVIC_SetPriority(EXTI0_IRQn, NVIC_EncodePriority(NVIC_GetPriorityGrouping(),0, 0));
  NVIC_EnableIRQ(EXTI0_IRQn);

}

/* USER CODE BEGIN 4 */

/**
  * @brief  This function Activate SPI1
  * @param  None
  * @retval None
  */
void Activate_SPI(void)
{
  /* Enable SPI1 */
  LL_SPI_Enable(SPI1);
}

/**
  * @brief  Turn-on LED2.
  * @param  None
  * @retval None
  */
void LED_On(void)
{
  /* Turn LED2 on */
  LL_GPIO_SetOutputPin(LED2_GPIO_Port, LED2_Pin);
}

/**
  * @brief  Set LED2 to Blinking mode for an infinite loop (toggle period based on value provided as input parameter).
  * @param  Period : Period of time (in ms) between each toggling of LED
  *   This parameter can be user defined values. Pre-defined values used in that example are :
  *     @arg LED_BLINK_FAST : Fast Blinking
  *     @arg LED_BLINK_SLOW : Slow Blinking
  *     @arg LED_BLINK_ERROR : Error specific Blinking
  * @retval None
  */
void LED_Blinking(uint32_t Period)
{
  /* Toggle LED2 in an infinite loop */
  while (1)
  {
    LL_GPIO_TogglePin(LED2_GPIO_Port, LED2_Pin);
    LL_mDelay(Period);
  }
}

/**
  * @brief  Wait end of transfer and check if received Data are well.
  * @param  None
  * @retval None
  */
void WaitAndCheckEndOfTransfer(void)
{
  /* 1 - Wait end of transmission */
  while (ubTransmitIndex != ubNbDataToTransmit)
  {
  }
  /* Disable TXE Interrupt */
  LL_SPI_DisableIT_TXE(SPI1);

  /* 2 - Wait end of reception */
  while (ubNbDataToReceive > ubReceiveIndex)
  {
  }
  /* Disable RXNE Interrupt */
  LL_SPI_DisableIT_RXNE(SPI1);

  /* 3 - Compare Transmit data to receive data */
  if (Buffercmp8((uint8_t *)aTxBuffer, (uint8_t *)aRxBuffer, ubNbDataToTransmit))
  {
    /* Processing Error */
    LED_Blinking(LED_BLINK_ERROR);
  }
  else
  {
    /* Turn On Led if data are well received */
    LED_On();
  }
}

/**
* @brief Compares two 8-bit buffers and returns the comparison result.
* @param pBuffer1: pointer to the source buffer to be compared to.
* @param pBuffer2: pointer to the second source buffer to be compared to the first.
* @param BufferLength: buffer's length.
* @retval   0: Comparison is OK (the two Buffers are identical)
*           Value different from 0: Comparison is NOK (Buffers are different)
*/
uint8_t Buffercmp8(uint8_t *pBuffer1, uint8_t *pBuffer2, uint8_t BufferLength)
{
  while (BufferLength--)
  {
    if (*pBuffer1 != *pBuffer2)
    {
      return 1;
    }

    pBuffer1++;
    pBuffer2++;
  }

  return 0;
}

/******************************************************************************/
/*   USER IRQ HANDLER TREATMENT Functions                                     */
/******************************************************************************/
/**
  * @brief  Function to manage User push-button (B1)
  * @param  None
  * @retval None
  */
void UserButton_Callback(void)
{
  /* Update User push-button (B1) variable : to be checked in waiting loop in main program */
  ubButtonPress = 1;
}

/**
  * @brief  Function called from SPI1 IRQ Handler when RXNE flag is set
  *         Function is in charge of retrieving received byte from SPI lines.
  * @param  None
  * @retval None
  */
void  SPI1_Rx_Callback(void)
{
  /* Read character in Data register.
  RXNE flag is cleared by reading data in DR register */
  aRxBuffer[ubReceiveIndex++] = LL_SPI_ReceiveData8(SPI1);
}

/**
  * @brief  Function called from SPI1 IRQ Handler when TXE flag is set
  *         Function is in charge  to transmit byte on SPI lines.
  * @param  None
  * @retval None
  */
void  SPI1_Tx_Callback(void)
{
  /* Write character in Data register.
  TXE flag is cleared by reading data in DR register */
  LL_SPI_TransmitData8(SPI1, aTxBuffer[ubTransmitIndex++]);
}

/**
  * @brief  Function called in case of error detected in SPI IT Handler
  * @param  None
  * @retval None
  */
void SPI1_TransferError_Callback(void)
{
  /* Disable RXNE  Interrupt             */
  LL_SPI_DisableIT_RXNE(SPI1);

  /* Disable TXE   Interrupt             */
  LL_SPI_DisableIT_TXE(SPI1);

  /* Set LED2 to Blinking mode to indicate error occurs */
  LED_Blinking(LED_BLINK_ERROR);
}

/* 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 */

  /* 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 */
