STM32CubeF4/Projects/STM32F412ZG-Nucleo/Examples/I2C/I2C_TwoBoards_AdvComIT/Src/main.c

/**
  ******************************************************************************
  * @file    I2C/I2C_TwoBoards_AdvComIT/Src/main.c
  * @author  MCD Application Team
  * @brief   This sample code shows how to use STM32F4xx I2C HAL API to transmit
  *          and receive a data buffer with a communication process based on
  *          IT transfer.
  *          The communication is done using 2 Boards.
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; COPYRIGHT(c) 2017 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 STM32F4xx_HAL_Examples
  * @{
  */

/** @addtogroup I2C_TwoBoards_AdvComIT
  * @{
  */

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Uncomment this line to use the board as master, if not it is used as slave */
#define MASTER_BOARD
#define I2C_ADDRESS        0x3E  /* Real 7 bits slave address value in Datasheet is: b0011111
                                    mean in uint8_t equivalent at 0x1F and this value can be
                                    seen in the OAR1 register in bits ADD[1:7] */
#define MASTER_REQ_READ    0x12
#define MASTER_REQ_WRITE   0x34

/* I2C SPEEDCLOCK define to max value: 400 KHz on STM32F4xx*/
#define I2C_SPEEDCLOCK   400000
#define I2C_DUTYCYCLE    I2C_DUTYCYCLE_2

/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* I2C handler declaration */
I2C_HandleTypeDef I2cHandle;


/* Buffer used for transmission */
uint8_t aTxBuffer[] = " ****I2C_TwoBoards communication based on IT****  ****I2C_TwoBoards communication based on IT****  ****I2C_TwoBoards communication based on IT**** ";

/* Buffer used for reception */
uint8_t aRxBuffer[RXBUFFERSIZE];
uint16_t hTxNumData = 0, hRxNumData = 0;
uint8_t bTransferRequest = 0;

/* Private function prototypes -----------------------------------------------*/
static void SystemClock_Config(void);
static uint16_t Buffercmp(uint8_t *pBuffer1, uint8_t *pBuffer2, uint16_t BufferLength);
static void Flush_Buffer(uint8_t* pBuffer, uint16_t BufferLength);
static void Error_Handler(void);

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

/**
  * @brief  Main program
  * @param  None
  * @retval None
  */
int main(void)
{

  /* STM32F4xx 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
     */
  HAL_Init();
  
  /* Configure the system clock to 100 MHz */
  SystemClock_Config();

  /* Configure LED1 and LED2 */
  BSP_LED_Init(LED1);
  BSP_LED_Init(LED2);
  

  /*##-1- Configure the I2C peripheral ######################################*/
  I2cHandle.Instance             = I2Cx;
  I2cHandle.Init.ClockSpeed      = I2C_SPEEDCLOCK;
  I2cHandle.Init.DutyCycle       = I2C_DUTYCYCLE;
  I2cHandle.Init.OwnAddress1     = I2C_ADDRESS;
  I2cHandle.Init.AddressingMode  = I2C_ADDRESSINGMODE_7BIT;
  I2cHandle.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE;
  I2cHandle.Init.OwnAddress2     = 0xFF;
  I2cHandle.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE;
  I2cHandle.Init.NoStretchMode   = I2C_NOSTRETCH_DISABLE;  
  
  if(HAL_I2C_Init(&I2cHandle) != HAL_OK)
  {
    /* Initialization Error */
    Error_Handler();
  }
  

#ifdef MASTER_BOARD
  
  /* Configure User push-button button */
  BSP_PB_Init(BUTTON_USER,BUTTON_MODE_GPIO);

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

  /* Delay to avoid that possible signal rebound is taken as button release */
  HAL_Delay(50);
  
  /* Wait for User push-button release before starting the Communication */
  while (BSP_PB_GetState(BUTTON_USER) != GPIO_PIN_RESET)
  {
  }

  while(1)
  {
    /* Initialize number of data variables */
    hTxNumData = TXBUFFERSIZE;
    hRxNumData = RXBUFFERSIZE;

    /* Update bTransferRequest to send buffer write request for Slave */
    bTransferRequest = MASTER_REQ_WRITE;

    /*##-2- Master sends write request for slave #############################*/
    do
    {
      if(HAL_I2C_Master_Transmit_IT(&I2cHandle, (uint16_t)I2C_ADDRESS, (uint8_t*)&bTransferRequest, 1)!= HAL_OK)
      {
        /* Error_Handler() function is called in case of error. */
        Error_Handler();
      }

      /* Before starting a new communication transfer, you need to check the current
      state of the peripheral; if it<EFBFBD>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(&I2cHandle) != HAL_I2C_STATE_READY)
      {
      }

      /* When Acknowledge failure occurs (Slave don't acknowledge its address)
      Master restarts communication */
    }
    while(HAL_I2C_GetError(&I2cHandle) == HAL_I2C_ERROR_AF); 

    /*##-3- Master sends number of data to be written ########################*/
    do
    {
      if(HAL_I2C_Master_Transmit_IT(&I2cHandle, (uint16_t)I2C_ADDRESS, (uint8_t*)&hTxNumData, 2)!= HAL_OK)
      {
        /* Error_Handler() function is called in case of error. */
        Error_Handler();
      }

      /* Before starting a new communication transfer, you need to check the current
      state of the peripheral; if it<EFBFBD>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(&I2cHandle) != HAL_I2C_STATE_READY)
      {
      }

      /* When Acknowledge failure occurs (Slave don't acknowledge its address)
      Master restarts communication */
    }
    while(HAL_I2C_GetError(&I2cHandle) == HAL_I2C_ERROR_AF); 

    /*##-4- Master sends aTxBuffer to slave ##################################*/
    do
    {
      if(HAL_I2C_Master_Transmit_IT(&I2cHandle, (uint16_t)I2C_ADDRESS, (uint8_t*)aTxBuffer, TXBUFFERSIZE)!= HAL_OK)
      {
        /* Error_Handler() function is called in case of error. */
        Error_Handler();
      }

      /* Before starting a new communication transfer, you need to check the current
      state of the peripheral; if it<EFBFBD>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(&I2cHandle) != HAL_I2C_STATE_READY)
      {
      }
      
      /* When Acknowledge failure occurs (Slave don't acknowledge its address)
      Master restarts communication */
    }
    while(HAL_I2C_GetError(&I2cHandle) == HAL_I2C_ERROR_AF); 

    /* Update bTransferRequest to send buffer read request for Slave */
    bTransferRequest = MASTER_REQ_READ;

    /*##-5- Master sends read request for slave ##############################*/
    do
    {
      if(HAL_I2C_Master_Transmit_IT(&I2cHandle, (uint16_t)I2C_ADDRESS, (uint8_t*)&bTransferRequest, 1)!= HAL_OK)
      {
        /* Error_Handler() function is called in case of error. */
        Error_Handler();
      }

      /* Before starting a new communication transfer, you need to check the current
      state of the peripheral; if it<EFBFBD>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(&I2cHandle) != HAL_I2C_STATE_READY)
      {
      }
      
      /* When Acknowledge failure occurs (Slave don't acknowledge its address)
      Master restarts communication */
    }
    while(HAL_I2C_GetError(&I2cHandle) == HAL_I2C_ERROR_AF); 

    /*##-6- Master sends number of data to be read ###########################*/
    do
    {
      if(HAL_I2C_Master_Transmit_IT(&I2cHandle, (uint16_t)I2C_ADDRESS, (uint8_t*)&hRxNumData, 2)!= HAL_OK)
      {
        /* Error_Handler() function is called in case of error. */
        Error_Handler();
      }
      
      /* Before starting a new communication transfer, you need to check the current
      state of the peripheral; if it<EFBFBD>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(&I2cHandle) != HAL_I2C_STATE_READY)
      {
      }
      
      /* When Acknowledge failure occurs (Slave don't acknowledge its address)
      Master restarts communication */
    }
    while(HAL_I2C_GetError(&I2cHandle) == HAL_I2C_ERROR_AF); 

    /*##-7- Master receives aRxBuffer from slave #############################*/
    do
    {
      if(HAL_I2C_Master_Receive_IT(&I2cHandle, (uint16_t)I2C_ADDRESS, (uint8_t*)aRxBuffer, RXBUFFERSIZE)!= HAL_OK)
      {
        /* Error_Handler() function is called in case of error. */
        Error_Handler();
      }

      /* Before starting a new communication transfer, you need to check the current
      state of the peripheral; if it<EFBFBD>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(&I2cHandle) != HAL_I2C_STATE_READY)
      {
      }
      
      /* When Acknowledge failure occurs (Slave don't acknowledge its address)
      Master restarts communication */
    }
    while(HAL_I2C_GetError(&I2cHandle) == HAL_I2C_ERROR_AF);

    /* Check correctness of received buffer ##################################*/
    if(Buffercmp((uint8_t*)aTxBuffer,(uint8_t*)aRxBuffer,hRxNumData))
    {
      /* Processing Error */
      Error_Handler();
    }

    /* Flush Rx buffers */
    Flush_Buffer((uint8_t*)aRxBuffer,RXBUFFERSIZE);

    /* Toggle LED1 */
    BSP_LED_Toggle(LED1);

    /* This delay permits to see LED1 toggling */
    HAL_Delay(25);
  }
#else
  while(1)
  {
    /* Initialize number of data variables */
    hTxNumData = 0;
    hRxNumData = 0;

    /*##-2- Slave receive request from master ################################*/
    while(HAL_I2C_Slave_Receive_IT(&I2cHandle, (uint8_t*)&bTransferRequest, 1)!= HAL_OK)
    {
    }

    /*  Before starting a new communication transfer, you need to check the current
    state of the peripheral; if it<EFBFBD>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(&I2cHandle) != HAL_I2C_STATE_READY)
    {
    }

    /* If master request write operation #####################################*/
    if (bTransferRequest == MASTER_REQ_WRITE)
    {
      /*##-3- Slave receive number of data to be read ########################*/
      while(HAL_I2C_Slave_Receive_IT(&I2cHandle, (uint8_t*)&hRxNumData, 2)!= HAL_OK);

      /*  Before starting a new communication transfer, you need to check the current
      state of the peripheral; if it<EFBFBD>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(&I2cHandle) != HAL_I2C_STATE_READY)
      {
      }

      /*##-4- Slave receives aRxBuffer from master ###########################*/
      while(HAL_I2C_Slave_Receive_IT(&I2cHandle, (uint8_t*)aRxBuffer, hRxNumData)!= HAL_OK);

      /*  Before starting a new communication transfer, you need to check the current
      state of the peripheral; if it<EFBFBD>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(&I2cHandle) != HAL_I2C_STATE_READY)
      {
      }

      /* Check correctness of received buffer ################################*/
      if(Buffercmp((uint8_t*)aTxBuffer,(uint8_t*)aRxBuffer,hRxNumData))
      {
        /* Processing Error */
        Error_Handler();
      }

      /* Flush Rx buffers */
      Flush_Buffer((uint8_t*)aRxBuffer,RXBUFFERSIZE);

      /* Toggle LED1 */
      BSP_LED_Toggle(LED1);
    }
    /* If master request write operation #####################################*/
    else
    {
      /*##-3- Slave receive number of data to be written #####################*/
      while(HAL_I2C_Slave_Receive_IT(&I2cHandle, (uint8_t*)&hTxNumData, 2)!= HAL_OK);

      /*  Before starting a new communication transfer, you need to check the current
      state of the peripheral; if it<EFBFBD>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(&I2cHandle) != HAL_I2C_STATE_READY)
      {
      }

      /*##-4- Slave transmit aTxBuffer to master #############################*/
      while(HAL_I2C_Slave_Transmit_IT(&I2cHandle, (uint8_t*)aTxBuffer, RXBUFFERSIZE)!= HAL_OK);

      /*  Before starting a new communication transfer, you need to check the current
      state of the peripheral; if it<EFBFBD>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(&I2cHandle) != HAL_I2C_STATE_READY)
      {
      }
    }
  }
#endif /* MASTER_BOARD */
}

/**
  * @brief  System Clock Configuration
  *         The system Clock is configured as follow : 
  *            System Clock source            = PLL (HSE)
  *            SYSCLK(Hz)                     = 100000000
  *            HCLK(Hz)                       = 100000000
  *            AHB Prescaler                  = 1
  *            APB1 Prescaler                 = 2
  *            APB2 Prescaler                 = 1
  *            HSE Frequency(Hz)              = 8000000
  *            PLL_M                          = 8
  *            PLL_N                          = 200
  *            PLL_P                          = 2
  *            PLL_Q                          = 7
  *            PLL_R                          = 2
  *            VDD(V)                         = 3.3
  *            Main regulator output voltage  = Scale1 mode
  *            Flash Latency(WS)              = 3
  * @param  None
  * @retval None
  */
static void SystemClock_Config(void)
{
  RCC_ClkInitTypeDef RCC_ClkInitStruct;
  RCC_OscInitTypeDef RCC_OscInitStruct;
  HAL_StatusTypeDef ret = HAL_OK;

  /* Enable Power Control clock */
  __HAL_RCC_PWR_CLK_ENABLE();

  /* The voltage scaling allows optimizing the power consumption when the device is 
     clocked below the maximum system frequency, to update the voltage scaling value 
     regarding system frequency refer to product datasheet.  */
  __HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);

  /* Enable HSE Oscillator and activate PLL with HSE as source */
  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
  RCC_OscInitStruct.HSEState = RCC_HSE_BYPASS;
  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
  RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
  RCC_OscInitStruct.PLL.PLLM = 8;
  RCC_OscInitStruct.PLL.PLLN = 200;
  RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
  RCC_OscInitStruct.PLL.PLLQ = 7;
  RCC_OscInitStruct.PLL.PLLR = 2;
  ret = HAL_RCC_OscConfig(&RCC_OscInitStruct);
  
  if(ret != HAL_OK)
  {
    while(1) { ; } 
  }

  /* Select PLL as system clock source and configure the HCLK, PCLK1 and PCLK2 
     clocks dividers */
  RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;  
  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;  
  ret = HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_3);
  if(ret != HAL_OK)
  {
    while(1) { ; }  
  }
}

/**
  * @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
  */
void HAL_I2C_ErrorCallback(I2C_HandleTypeDef *I2cHandle)
{
  /** Error_Handler() function is called when error occurs.
  * 1- When Slave don't acknowledge it's address, Master restarts communication.
  * 2- When Master don't acknowledge the last data transferred, Slave don't care in this example.
  */
  if (HAL_I2C_GetError(I2cHandle) != HAL_I2C_ERROR_AF)
  {
    Error_Handler();
  }
}

/**
  * @brief  This function is executed in case of error occurrence.
  * @param  None
  * @retval None
  */
static void Error_Handler(void)
{
  /* Turn Off LED1 */
  BSP_LED_Off(LED1);
  /* Turn On LED2 */
  BSP_LED_On(LED2);
  while(1)
  {
  }
}

/**
  * @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;
}

/**
  * @brief  Flushes the buffer
  * @param  pBuffer: buffers to be flushed.
  * @param  BufferLength: buffer's length
  * @retval None
  */
static void Flush_Buffer(uint8_t* pBuffer, uint16_t BufferLength)
{
  while (BufferLength--)
  {
    *pBuffer = 0;

    pBuffer++;
  }
}
#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 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) */

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


/**
  * @}
  */

/**
  * @}
  */

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