/**
  ******************************************************************************
  * @file    Examples_LL/I2C/I2C_OneBoard_Communication_IT_Init/Src/main.c
  * @author  MCD Application Team
  * @brief   This example describes how to send/receive bytes over I2C IP using
  *          the STM32F0xx I2C LL API.
  *          Peripheral initialization done using LL initialization function.
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; COPYRIGHT(c) 2016 STMicroelectronics</center></h2>
  *
  * Redistribution and use in source and binary forms, with or without modification,
  * are permitted provided that the following conditions are met:
  *   1. Redistributions of source code must retain the above copyright notice,
  *      this list of conditions and the following disclaimer.
  *   2. Redistributions in binary form must reproduce the above copyright notice,
  *      this list of conditions and the following disclaimer in the documentation
  *      and/or other materials provided with the distribution.
  *   3. Neither the name of STMicroelectronics nor the names of its contributors
  *      may be used to endorse or promote products derived from this software
  *      without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  ******************************************************************************
  */

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

/** @addtogroup STM32F0xx_LL_Examples
  * @{
  */

/** @addtogroup I2C_OneBoard_Communication_IT_Init
  * @{
  */

/* Private typedef -----------------------------------------------------------*/
LL_I2C_InitTypeDef i2c_initstruct;

/* Private define ------------------------------------------------------------*/
/**
  * @brief I2C devices settings
  */
/* Timing register value is computed with the STM32CubeMX Tool,
  * Fast Mode @400kHz with I2CCLK = 48 MHz,
  * rise time = 100ns, fall time = 10ns
  * Timing Value = (uint32_t)0x00901850
  */
#define I2C_TIMING               0x00901850

/**
  * @brief Define related to SlaveTransmit process
  */
#define SLAVE_BYTE_TO_SEND       (uint8_t)0xA5

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

/* Private variables ---------------------------------------------------------*/
__IO uint8_t ubButtonPress       = 0;

/**
  * @brief Variables related to MasterReceive process
  */
uint8_t      aReceiveBuffer[0xF] = {0};
__IO uint8_t ubReceiveIndex      = 0;

/* Private function prototypes -----------------------------------------------*/
void     SystemClock_Config(void);
void     Configure_I2C_Slave(void);
void     Configure_I2C_Master(void);
void     LED_Init(void);
void     LED_On(void);
void     LED_Off(void);
void     LED_Blinking(uint32_t Period);
void     WaitForUserButtonPress(void);
void     Handle_I2C_Master(void);
void     UserButton_Init(void);

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

/**
  * @brief  Main program
  * @param  None
  * @retval None
  */
int main(void)
{
  /* Configure the system clock to 48 MHz */
  SystemClock_Config();

  /* Initialize LED2 */
  LED_Init();

  /* Set LED2 Off */
  LED_Off();

  /* Initialize User push-button in EXTI mode */
  UserButton_Init();

  /* Configure I2C1 (I2C IP configuration in Slave mode and related GPIO initialization) */
  Configure_I2C_Slave();

  /* Configure I2C2 (I2C IP configuration in Master mode and related GPIO initialization) */
  Configure_I2C_Master();

  /* Wait for User push-button press to start transfer */
  WaitForUserButtonPress();

  /* Handle I2C2 events (Master) */
  Handle_I2C_Master();

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

/**
  * @brief  This function configures I2C1 in Slave mode.
  * @note   This function is used to :
  *         -1- Enables GPIO clock and configures the I2C1 pins.
  *         -2- Enable the I2C1 peripheral clock and I2C1 clock source.
  *         -3- Configure NVIC for I2C1.
  *         -4- Configure and Enable I2C1 functional parameters.
  *         -5- Enable I2C1 address match/error interrupts.
  * @note   Peripheral configuration is minimal configuration from reset values.
  *         Thus, some useless LL unitary functions calls below are provided as
  *         commented examples - setting is default configuration from reset.
  * @param  None
  * @retval None
  */
void Configure_I2C_Slave(void)
{
  /* (1) Enables GPIO clock and configures the I2C1 pins **********************/
  /*    (SCL on PB.6, SDA on PB.7)                     **********************/

  /* Enable the peripheral clock of GPIOB */
  LL_AHB1_GRP1_EnableClock(LL_AHB1_GRP1_PERIPH_GPIOB);

  /* Configure SCL Pin as : Alternate function, High Speed, Open drain, Pull up */
  LL_GPIO_SetPinMode(GPIOB, LL_GPIO_PIN_6, LL_GPIO_MODE_ALTERNATE);
  LL_GPIO_SetAFPin_0_7(GPIOB, LL_GPIO_PIN_6, LL_GPIO_AF_1);
  LL_GPIO_SetPinSpeed(GPIOB, LL_GPIO_PIN_6, LL_GPIO_SPEED_FREQ_HIGH);
  LL_GPIO_SetPinOutputType(GPIOB, LL_GPIO_PIN_6, LL_GPIO_OUTPUT_OPENDRAIN);
  LL_GPIO_SetPinPull(GPIOB, LL_GPIO_PIN_6, LL_GPIO_PULL_UP);

  /* Configure SDA Pin as : Alternate function, High Speed, Open drain, Pull up */
  LL_GPIO_SetPinMode(GPIOB, LL_GPIO_PIN_7, LL_GPIO_MODE_ALTERNATE);
  LL_GPIO_SetAFPin_0_7(GPIOB, LL_GPIO_PIN_7, LL_GPIO_AF_1);
  LL_GPIO_SetPinSpeed(GPIOB, LL_GPIO_PIN_7, LL_GPIO_SPEED_FREQ_HIGH);
  LL_GPIO_SetPinOutputType(GPIOB, LL_GPIO_PIN_7, LL_GPIO_OUTPUT_OPENDRAIN);
  LL_GPIO_SetPinPull(GPIOB, LL_GPIO_PIN_7, LL_GPIO_PULL_UP);

  /* (2) Enable the I2C1 peripheral clock and I2C1 clock source ***************/

  /* Enable the peripheral clock for I2C1 */
  LL_APB1_GRP1_EnableClock(LL_APB1_GRP1_PERIPH_I2C1);

  /* Set I2C1 clock source as SYSCLK */
  LL_RCC_SetI2CClockSource(LL_RCC_I2C1_CLKSOURCE_SYSCLK);

  /* (3) Configure NVIC for I2C1 **********************************************/

  /* Configure Event and Error IT:
   *  - Set priority for I2C1_IRQn
   *  - Enable I2C1_IRQn
   */
  NVIC_SetPriority(I2C1_IRQn, 0);
  NVIC_EnableIRQ(I2C1_IRQn);

  /* (4) Configure I2C1 functional parameters *********************************/

  /* Reset I2C1 data registers */
  if (LL_I2C_DeInit(I2C1) != SUCCESS) 
  {
    /* Initialization Error */
    LED_Blinking(LED_BLINK_ERROR);
  }

  /* Enable Clock stretching */
  /* Reset Value is Clock stretching enabled */
  //LL_I2C_EnableClockStretching(I2C1);

  /* Enable General Call                  */
  /* Reset Value is General Call disabled */
  //LL_I2C_EnableGeneralCall(I2C1);

  /* Configure the 7bits Own Address2               */
  /* Reset Values of :
   *     - OwnAddress2 is 0x00
   *     - OwnAddrMask is LL_I2C_OWNADDRESS2_NOMASK
   *     - Own Address2 is disabled
   */
  //LL_I2C_SetOwnAddress2(I2C1, 0x00, LL_I2C_OWNADDRESS2_NOMASK);
  //LL_I2C_DisableOwnAddress2(I2C1);

  /* Enable Peripheral in I2C mode */
  /* Reset Value is I2C mode */
  //LL_I2C_SetMode(I2C1, LL_I2C_MODE_I2C);

  /* Set fields of initialization structure:
   *  - Peripheral Mode     = Mode I2C
   *  - Timing Value        = fast Mode @400kHz with I2CCLK = 48 MHz
   *                          rise time = 100ns, 
   *                          fall time = 10ns
   *  - Analog Filter       = Enabled
   *  - Digital Filter      = Disabled
   *  - Own Address1        = SLAVE_OWN_ADDRESS
   *  - Type of Acknowledge = Acknowledge bytes/address received
   *  - Own Address 1 Size  = Slave Address in 7-bit
  */
  i2c_initstruct.PeripheralMode  = LL_I2C_MODE_I2C;
  i2c_initstruct.Timing          = I2C_TIMING;
  i2c_initstruct.AnalogFilter    = LL_I2C_ANALOGFILTER_ENABLE;
  i2c_initstruct.DigitalFilter   = 0x00;
  i2c_initstruct.OwnAddress1     = SLAVE_OWN_ADDRESS;
  i2c_initstruct.TypeAcknowledge = LL_I2C_ACK;
  i2c_initstruct.OwnAddrSize     = LL_I2C_OWNADDRESS1_7BIT;

  /* Initialize I2C instance according to parameters defined in initialization structure. */  
  if (LL_I2C_Init(I2C1, &i2c_initstruct) != SUCCESS)
  {
    /* Initialization Error */
    LED_Blinking(LED_BLINK_ERROR);
  }

  /* (5) Enable I2C1 address match/error interrupts:
   *  - Enable Address Match Interrupt
   *  - Enable Not acknowledge received interrupt
   *  - Enable Error interrupts
   *  - Enable Stop interrupt
   */
  LL_I2C_EnableIT_ADDR(I2C1);
  LL_I2C_EnableIT_NACK(I2C1);
  LL_I2C_EnableIT_ERR(I2C1);
  LL_I2C_EnableIT_STOP(I2C1);
}

/**
  * @brief  This function configures I2C2 in Master mode.
  * @note   This function is used to :
  *         -1- Enables GPIO clock and configures the I2C2 pins.
  *         -2- Enable the I2C2 peripheral clock.
  *         -3- Configure NVIC for I2C2.
  *         -4- Configure and Enable I2C2 functional parameters.
  *         -5- Enable I2C2 transfer complete/error interrupts.
  * @note   Peripheral configuration is minimal configuration from reset values.
  *         Thus, some useless LL unitary functions calls below are provided as
  *         commented examples - setting is default configuration from reset.
  * @param  None
  * @retval None
  */
void Configure_I2C_Master(void)
{
  /* (1) Enables GPIO clock and configures the I2C2 pins **********************/
  /*    (SCL on PB.13, SDA on PB.14)                     **********************/

  /* Enable the peripheral clock of GPIOB */
  LL_AHB1_GRP1_EnableClock(LL_AHB1_GRP1_PERIPH_GPIOB);

  /* Configure SCL Pin as : Alternate function, High Speed, Open drain, Pull up */
  LL_GPIO_SetPinMode(GPIOB, LL_GPIO_PIN_13, LL_GPIO_MODE_ALTERNATE);
  LL_GPIO_SetAFPin_8_15(GPIOB, LL_GPIO_PIN_13, LL_GPIO_AF_5);
  LL_GPIO_SetPinSpeed(GPIOB, LL_GPIO_PIN_13, LL_GPIO_SPEED_FREQ_HIGH);
  LL_GPIO_SetPinOutputType(GPIOB, LL_GPIO_PIN_13, LL_GPIO_OUTPUT_OPENDRAIN);
  LL_GPIO_SetPinPull(GPIOB, LL_GPIO_PIN_13, LL_GPIO_PULL_UP);

  /* Configure SDA Pin as : Alternate function, High Speed, Open drain, Pull up */
  LL_GPIO_SetPinMode(GPIOB, LL_GPIO_PIN_14, LL_GPIO_MODE_ALTERNATE);
  LL_GPIO_SetAFPin_8_15(GPIOB, LL_GPIO_PIN_14, LL_GPIO_AF_5);
  LL_GPIO_SetPinSpeed(GPIOB, LL_GPIO_PIN_14, LL_GPIO_SPEED_FREQ_HIGH);
  LL_GPIO_SetPinOutputType(GPIOB, LL_GPIO_PIN_14, LL_GPIO_OUTPUT_OPENDRAIN);
  LL_GPIO_SetPinPull(GPIOB, LL_GPIO_PIN_14, LL_GPIO_PULL_UP);

  /* (2) Enable the I2C2 peripheral clock *************************************/

  /* Enable the peripheral clock for I2C2 */
  LL_APB1_GRP1_EnableClock(LL_APB1_GRP1_PERIPH_I2C2);

  /* (3) Configure NVIC for I2C2 **********************************************/

  /* Configure Event and Error IT:
   *  - Set priority for I2C2_IRQn
   *  - Enable I2C2_IRQn
   */
  NVIC_SetPriority(I2C2_IRQn, 0);
  NVIC_EnableIRQ(I2C2_IRQn);

  /* (4) Configure I2C2 functional parameters ********************************/
  /* Reset I2C2 data registers */
  if (LL_I2C_DeInit(I2C2) != SUCCESS) 
  {
    /* Initialization Error */
    LED_Blinking(LED_BLINK_ERROR);
  }

  /* Enable General Call                  */
  /* Reset Value is General Call disabled */
  //LL_I2C_EnableGeneralCall(I2C2);

  /* Configure the 7bits Own Address2               */
  /* Reset Values of :
   *     - OwnAddress2 is 0x00
   *     - OwnAddrMask is LL_I2C_OWNADDRESS2_NOMASK
   *     - Own Address2 is disabled
   */
  //LL_I2C_SetOwnAddress2(I2C2, 0x00, LL_I2C_OWNADDRESS2_NOMASK);
  //LL_I2C_DisableOwnAddress2(I2C2);

  /* Configure the Master to operate in 7-bit or 10-bit addressing mode */
  /* Reset Value is LL_I2C_ADDRESSING_MODE_7BIT                         */
  //LL_I2C_SetMasterAddressingMode(I2C2, LL_I2C_ADDRESSING_MODE_7BIT);

  /* Enable Peripheral in I2C mode */
  /* Reset Value is I2C mode */
  //LL_I2C_SetMode(I2C2, LL_I2C_MODE_I2C);

  /* Set fields of initialization structure:
   *  - Peripheral Mode     = Mode I2C
   *  - Timing Value        = fast Mode @400kHz with I2CCLK = 48 MHz
   *                          rise time = 100ns, 
   *                          fall time = 10ns
   *  - Analog Filter       = Enabled
   *  - Digital Filter      = Disabled
   *  - Own Address1        = No own address 1
   *  - Type of Acknowledge = Acknowledge bytes/address received
   *  - Own Address 1 Size  = default value Slave Address in 7-bit
  */
  i2c_initstruct.PeripheralMode  = LL_I2C_MODE_I2C;
  i2c_initstruct.Timing          = I2C_TIMING;
  i2c_initstruct.AnalogFilter    = LL_I2C_ANALOGFILTER_ENABLE;
  i2c_initstruct.DigitalFilter   = 0x00;
  i2c_initstruct.OwnAddress1     = 0x00;
  i2c_initstruct.TypeAcknowledge = LL_I2C_ACK;
  i2c_initstruct.OwnAddrSize     = LL_I2C_OWNADDRESS1_7BIT;

  /* Initialize I2C instance according to parameters defined in initialization structure. */  
  if (LL_I2C_Init(I2C2, &i2c_initstruct) != SUCCESS)
  {
    /* Initialization Error */
    LED_Blinking(LED_BLINK_ERROR);
  }

  /* (5) Enable I2C2 transfer complete/error interrupts:
   *  - Enable Receive Interrupt
   *  - Enable Not acknowledge received interrupt
   *  - Enable Error interrupts
   *  - Enable Stop interrupt
   */
  LL_I2C_EnableIT_RX(I2C2);
  LL_I2C_EnableIT_NACK(I2C2);
  LL_I2C_EnableIT_ERR(I2C2);
  LL_I2C_EnableIT_STOP(I2C2);
}

/**
  * @brief  Initialize LED2.
  * @param  None
  * @retval None
  */
void LED_Init(void)
{
  /* Enable the LED2 Clock */
  LED2_GPIO_CLK_ENABLE();

  /* Configure IO in output push-pull mode to drive external LED2 */
  LL_GPIO_SetPinMode(LED2_GPIO_PORT, LED2_PIN, LL_GPIO_MODE_OUTPUT);
  /* Reset value is LL_GPIO_OUTPUT_PUSHPULL */
  //LL_GPIO_SetPinOutputType(LED2_GPIO_PORT, LED2_PIN, LL_GPIO_OUTPUT_PUSHPULL);
  /* Reset value is LL_GPIO_SPEED_FREQ_LOW */
  //LL_GPIO_SetPinSpeed(LED2_GPIO_PORT, LED2_PIN, LL_GPIO_SPEED_FREQ_LOW);
  /* Reset value is LL_GPIO_PULL_NO */
  //LL_GPIO_SetPinPull(LED2_GPIO_PORT, LED2_PIN, LL_GPIO_PULL_NO);
}

/**
  * @brief  Turn-on LED2.
  * @param  None
  * @retval None
  */
void LED_On(void)
{
  /* Turn LED2 on */
  LL_GPIO_SetOutputPin(LED2_GPIO_PORT, LED2_PIN);
}

/**
  * @brief  Turn-off LED2.
  * @param  None
  * @retval None
  */
void LED_Off(void)
{
  /* Turn LED2 off */
  LL_GPIO_ResetOutputPin(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)
{
  /* Turn LED2 on */
  LL_GPIO_SetOutputPin(LED2_GPIO_PORT, LED2_PIN);

  /* Toggle IO in an infinite loop */
  while (1)
  {
    LL_GPIO_TogglePin(LED2_GPIO_PORT, LED2_PIN);  
    LL_mDelay(Period);
  }
}

/**
  * @brief  Configures User push-button in GPIO or EXTI Line Mode.
  * @param  None 
  * @retval None
  */
void UserButton_Init(void)
{
  /* Enable the BUTTON Clock */
  USER_BUTTON_GPIO_CLK_ENABLE();

  /* Configure GPIO for BUTTON */
  LL_GPIO_SetPinMode(USER_BUTTON_GPIO_PORT, USER_BUTTON_PIN, LL_GPIO_MODE_INPUT);
  LL_GPIO_SetPinPull(USER_BUTTON_GPIO_PORT, USER_BUTTON_PIN, LL_GPIO_PULL_NO);

  /* Connect External Line to the GPIO*/
  USER_BUTTON_SYSCFG_SET_EXTI();

  /* Enable a rising trigger External line 13 Interrupt */
  USER_BUTTON_EXTI_LINE_ENABLE();
  USER_BUTTON_EXTI_FALLING_TRIG_ENABLE();

  /* Configure NVIC for USER_BUTTON_EXTI_IRQn */
  NVIC_EnableIRQ(USER_BUTTON_EXTI_IRQn); 
  NVIC_SetPriority(USER_BUTTON_EXTI_IRQn,0x03);  
}

/**
  * @brief  Wait for User push-button press to start transfer.
  * @param  None 
  * @retval None
  */
  /*  */
void WaitForUserButtonPress(void)
{
  while (ubButtonPress == 0)
  {
    LL_GPIO_TogglePin(LED2_GPIO_PORT, LED2_PIN);
    LL_mDelay(LED_BLINK_FAST);
  }
  /* Turn LED2 off */
  LL_GPIO_ResetOutputPin(LED2_GPIO_PORT, LED2_PIN);
}

/**
  * @brief  This Function handle Master events to perform a reception process
  * @note  This function is composed in one step :
  *        -1- Initiate a Start condition to the Slave device.
  * @param  None
  * @retval None
  */
void Handle_I2C_Master(void)
{
  /* (1) Initiate a Start condition to the Slave device ***********************/

  /* Master Generate Start condition for a read request:
   *  - to the Slave with a 7-Bit SLAVE_OWN_ADDRESS
   *  - with a auto stop condition generation when receive 1 byte
   */
  LL_I2C_HandleTransfer(I2C2, SLAVE_OWN_ADDRESS, LL_I2C_ADDRSLAVE_7BIT, 1, LL_I2C_MODE_AUTOEND, LL_I2C_GENERATE_START_READ);
}

/**
  * @brief  System Clock Configuration
  *         The system Clock is configured as follow : 
  *            System Clock source            = PLL (HSI48)
  *            SYSCLK(Hz)                     = 48000000
  *            HCLK(Hz)                       = 48000000
  *            AHB Prescaler                  = 1
  *            APB1 Prescaler                 = 1
  *            HSI Frequency(Hz)              = 48000000
  *            PREDIV                         = 2
  *            PLLMUL                         = 2
  *            Flash Latency(WS)              = 1
  * @param  None
  * @retval None
  */
void SystemClock_Config(void)
{
  /* Set FLASH latency */ 
  LL_FLASH_SetLatency(LL_FLASH_LATENCY_1);

  /* Enable HSI48 and wait for activation*/
  LL_RCC_HSI48_Enable(); 
  while(LL_RCC_HSI48_IsReady() != 1) 
  {
  };
  
  /* Main PLL configuration and activation */
  LL_RCC_PLL_ConfigDomain_SYS(LL_RCC_PLLSOURCE_HSI48, LL_RCC_PLL_MUL_2, LL_RCC_PREDIV_DIV_2);
  
  LL_RCC_PLL_Enable();
  while(LL_RCC_PLL_IsReady() != 1)
  {
  };
  
  /* Sysclk activation on the main PLL */
  LL_RCC_SetAHBPrescaler(LL_RCC_SYSCLK_DIV_1);
  LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_PLL);
  while(LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_PLL)
  {
  };
  
  /* Set APB1 prescaler */
  LL_RCC_SetAPB1Prescaler(LL_RCC_APB1_DIV_1);
  
  /* Set systick to 1ms in using frequency set to 48MHz */
  /* This frequency can be calculated through LL RCC macro */
  /* ex: __LL_RCC_CALC_PLLCLK_FREQ (HSI48_VALUE, LL_RCC_PLL_MUL_2, LL_RCC_PREDIV_DIV_2) */
  LL_Init1msTick(48000000);
  
  /* Update CMSIS variable (which can be updated also through SystemCoreClockUpdate function) */
  LL_SetSystemCoreClock(48000000);
}
/******************************************************************************/
/*   IRQ HANDLER TREATMENT Functions                                          */
/******************************************************************************/
/**
  * @brief  Function to manage User push-button
  * @param  None
  * @retval None
  */
void UserButton_Callback(void)
{
  /* Update User push-button variable : to be checked in waiting loop in main program */
  ubButtonPress = 1;
}

/**
  * @brief  Function called from I2C IRQ Handler when TXIS flag is set
  *         Function is in charge of transmit a byte on I2C lines.
  * @param  None
  * @retval None
  */
void Slave_Ready_To_Transmit_Callback(void)
{
  /* Send the Byte requested by the Master */
  LL_I2C_TransmitData8(I2C1, SLAVE_BYTE_TO_SEND);
}

/**
  * @brief  Function called from I2C IRQ Handler when RXNE flag is set
  *         Function is in charge of reading byte received on I2C lines.
  * @param  None
  * @retval None
  */
void Master_Reception_Callback(void)
{
  /* Read character in Receive Data register.
  RXNE flag is cleared by reading data in RXDR register */
  aReceiveBuffer[ubReceiveIndex++] = LL_I2C_ReceiveData8(I2C2);
}

/**
  * @brief  Function called from I2C IRQ Handler when STOP flag is set
  *         Function is in charge of checking data received,
  *         LED2 is On if data are correct.
  * @param  None
  * @retval None
  */
void Master_Complete_Callback(void)
{
  /* Read Received character.
  RXNE flag is cleared by reading of RXDR register */
  if(aReceiveBuffer[ubReceiveIndex-1] == SLAVE_BYTE_TO_SEND)
  {
    /* Turn LED2 On:
     * - Expected byte has been received
     * - Master Rx sequence completed successfully
     */
    LED_On();
  }
  else
  {
    /* Call Error function */
    Error_Callback();
  }
}

/**
  * @brief  Function called in case of error detected in I2C IT Handler
  * @param  None
  * @retval None
  */
void Error_Callback(void)
{
  /* Disable I2C1_IRQn and I2C2_IRQn */
  NVIC_DisableIRQ(I2C1_IRQn);
  NVIC_DisableIRQ(I2C2_IRQn);

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

#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(char *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", file, line) */

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

/**
  * @}
  */

/**
  * @}
  */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
