stm32f0 iic从机

乐乐棠提问时间：2020-6-24 09:54 /

问答
是否解决:

   最近在捣鼓stm32f0的IIC从机，之前一直使用的是IIC主机，IIC主机主要用的是IO口模拟的，实现起来没什么问题。但是转到IIC从机后，发现通信读取数据过程中偶尔会出现串码的现象，大概一小时会出现两三次。以下是IIC从机的部分代码：

/*-- defined -----------------------------------------------------------------*/
#define    SLAVE_ADDR             0x16

#define    POLYNOME                0x07

#define    I2C_REC_BYTES          64
#define    I2C_TX_BYTES             64

/*-- private variables -------------------------------------------------------*/
static I2C_HandleTypeDef  hi2c1;

static u8_t    slaveTxBuff[I2C_TX_BYTES] = {0};
static u8_t    slaveRxBuff[I2C_REC_BYTES] = {0};

static  u8_t    rsoc;
static  u16_t battVolt;
static  s16_t current;
static  u16_t Temper;
static  u16_t cellVolt[3];

/*-- functions ---------------------------------------------------------------*/
static  void  tx_match(u8_t cmd);

/**@brief
  * @brief    IIC初始化
  * @param
  * @return
  */

void hal_iic_init(void)
{
  u32_t  tmpisr = 0;

  /* Peripheral clock enable */
  __HAL_RCC_I2C1_CLK_ENABLE();

  hi2c1.Instance = I2C1;
  hi2c1.Init.Timing = 0x2000090E;
  hi2c1.Init.OwnAddress1 = SLAVE_ADDR;
  hi2c1.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
  hi2c1.Init.DualAddressMode = I2C_DUALADDRESS_DISABLE;
  hi2c1.Init.OwnAddress2 = 0;
  hi2c1.Init.OwnAddress2Masks = I2C_OA2_NOMASK;
  hi2c1.Init.GeneralCallMode = I2C_GENERALCALL_DISABLE;
  hi2c1.Init.NoStretchMode = I2C_NOSTRETCH_ENABLE;
  if (HAL_I2C_Init(&hi2c1) != HAL_OK)
  {

  }

  /* Configure Analogue filter */
  if (HAL_I2CEx_ConfigAnalogFilter(&hi2c1, I2C_ANALOGFILTER_ENABLE) != HAL_OK)
  {

  }

  /* Configure Digital filter */
  if (HAL_I2CEx_ConfigDigitalFilter(&hi2c1, 0) != HAL_OK)
  {

  }

  /* I2C1 interrupt Init */
  HAL_NVIC_SetPriority(I2C1_IRQn, 0, 0);
  HAL_NVIC_EnableIRQ(I2C1_IRQn);

  /**
   I2C_IT_ADDRI:    Address match interrupt.
   I2C_IT_STOPI:    STOP detection interrupt.
   I2C_IT_NACKI:    NACK received interrupt.
   I2C_IT_ERRI:    Errors interrupt.
   I2C_IT_TCI:    TC interrupt.
   I2C_XFER_RX_IT: REC interrupt.
  */
  tmpisr |= I2C_IT_ADDRI | I2C_IT_STOPI | I2C_IT_NACKI | I2C_IT_ERRI | I2C_IT_RXI | I2C_IT_TXI;
  __HAL_I2C_ENABLE_IT(&hi2c1, tmpisr);
}

/**@brief
  * @brief
  * @param
  * @return
  */
void  i2c_err_irq_handler(I2C_HandleTypeDef *hi2c, u32_t isrFlag)
{
  if((isrFlag & I2C_FLAG_ARLO) == I2C_FLAG_ARLO)
  { /* ARLO Err */
__HAL_I2C_CLEAR_FLAG(hi2c, I2C_FLAG_ARLO);
  }

  if((isrFlag & I2C_FLAG_BERR) == I2C_FLAG_BERR)
  { /* BERR Err */
__HAL_I2C_CLEAR_FLAG(hi2c, I2C_FLAG_BERR);
  }

  if((isrFlag & I2C_FLAG_OVR) == I2C_FLAG_OVR)
  { /* OVR Err */
__HAL_I2C_CLEAR_FLAG(hi2c, I2C_FLAG_OVR);
  }
}

/**@brief
  * @brief
  * @param
  * @return
  */
void  i2c_evt_irq_handler(I2C_HandleTypeDef *hi2c, u32_t isrFlag)
{
  static u8_t txCounter = 0;
  static u8_t rxCounter = 0;
  u32_t  transferDir = 0;

  if(hi2c->Instance == hi2c1.Instance)
  {
if((isrFlag & I2C_FLAG_ADDR) == I2C_FLAG_ADDR)
{
   /* EV1 */
   transferDir = isrFlag & I2C_ISR_DIR;
   /* 判断方向 */
   if(transferDir)
   {
      /* 方向为从机发送 */
      I2C1->ISR |= I2C_ISR_TXE;
      I2C1->TXDR = slaveTxBuff[0];
      txCounter = 1;
      }
   else
   {
      /* 方向为从机接收 */
      rxCounter = 0;
   }

   __HAL_I2C_CLEAR_FLAG(hi2c, I2C_FLAG_ADDR);
}
else if((isrFlag & I2C_FLAG_TXIS) == I2C_FLAG_TXIS)
{
   /* EV3 */
   I2C1->TXDR = slaveTxBuff[txCounter++];
}
else if((isrFlag & I2C_FLAG_RXNE) == I2C_FLAG_RXNE)
{
   /* EV2 */
   if(rxCounter < I2C_REC_BYTES)
   {
      slaveRxBuff[rxCounter] = hi2c->Instance->RXDR;

      /* 进行命令匹配 */
      if(rxCounter == 0)
      {
            tx_match(slaveRxBuff[0]);
      }

         rxCounter++;
   }
}
else if((isrFlag & I2C_FLAG_STOPF) == I2C_FLAG_STOPF)
{
   /* EV4 */
   hi2c->Instance->ISR |= I2C_ISR_TXE;
   hi2c->Instance->ISR |= I2C_ISR_TXIS;
   txCounter = 0;
   rxCounter = 0;
   __HAL_I2C_CLEAR_FLAG(hi2c, I2C_FLAG_STOPF);
   }
else if((isrFlag & I2C_FLAG_AF) == I2C_FLAG_AF)
{
   /* EV3_2 */
   __HAL_I2C_CLEAR_FLAG(hi2c, I2C_FLAG_AF);
   }
  }
}

/**
  * @brief This function handles I2C1 global interrupt.
  * @param
  * @param
  * @return
  */
void I2C1_IRQHandler(void)
{
  u32_t isrFlag = 0;

  isrFlag = hi2c1.Instance->ISR;

  if (isrFlag & (I2C_FLAG_BERR | I2C_FLAG_ARLO | I2C_FLAG_OVR))
  {
   /* 异常处理 */
   //HAL_I2C_ER_IRQHandler(&hi2c1);
   i2c_err_irq_handler(&hi2c1, isrFlag);
  }
  else
  {
   /* 事件处理 */
   //HAL_I2C_EV_IRQHandler(&hi2c1);
   i2c_evt_irq_handler(&hi2c1, isrFlag);
  }
}

/** @function
  * @brief    IIC从机匹配发送数据，发现如果使用switch-case出错率会更高，不知为何。
  * @param
  * @return
  */
static  void  tx_match(u8_t cmd)
{
  u8_t  counter = 0;

  if(cmd == 0x08)
  {
slaveTxBuff[counter++] = Temper&0x00ff;
slaveTxBuff[counter++] = (Temper&0xff00)>>8;
Temper++;
  }
  else if(cmd == 0x09)
  {
slaveTxBuff[counter++] = battVolt&0x00ff;
slaveTxBuff[counter++] = (battVolt&0xff00)>>8;
battVolt++;
  }
  else if(cmd == 0x0A)
  {
slaveTxBuff[counter++] = current&0x00ff;
slaveTxBuff[counter++] = (current&0xff00)>>8;
  }
  else if(cmd == 0x0D)
  {
slaveTxBuff[counter++] = rsoc&0x00ff;
slaveTxBuff[counter++] = (rsoc&0xff00)>>8;
  }
  else if(cmd == 0x3F)
  {
slaveTxBuff[counter++] = cellVolt[0]&0x00ff;
slaveTxBuff[counter++] = (cellVolt[0]&0xff00)>>8;
  }
  else if(cmd == 0x3E)
  {
slaveTxBuff[counter++] = cellVolt[1]&0x00ff;
slaveTxBuff[counter++] = (cellVolt[1]&0xff00)>>8;
  }
  else if(cmd == 0x3D)
  {
slaveTxBuff[counter++] = cellVolt[2]&0x00ff;
slaveTxBuff[counter++] = (cellVolt[2]&0xff00)>>8;
  }

  slaveTxBuff[counter] = CRC8(slaveTxBuff, counter, POLYNOME);
}

可能是因为本人对IIC从机原理理解得不够深，折腾了两天还是没什么进展，望由此经验的朋友多多指教，谢谢！