通过 STM32CUBEMX 的低层函数在中断模式下两个 stm32 板之间的 I2C 通信

Question

我正在做一个需要两个stm32 (stm32f103rb and stm32f429zg)之间数据通信的项目。

我使用stm32f103rb-nucleo examples_ll (I2C _OneBoard_Communication_IT)但它只工作一个字节，之后就停止工作。 我希望它重复工作。

代码结构与示例在与stm32cubemx存储库相关的文件夹中的编写方式完全相同。

我不知道如何让它循环工作，通过按下按钮，每次按下主从按钮时，通信就会完成。

我已将主完成回调 function 放在这里：

void Master_Complete_Callback(void)
{
  if(ubNbDataToReceive == 3)
  {
    /* Prepare the generation of a Non ACKnowledge condition after next received bytes */
    LL_I2C_AcknowledgeNextData(I2C1, LL_I2C_NACK);
    
    /* Read character in Receive Data register.
    RXNE flag is cleared by reading data in RXDR register */
    aReceiveBuffer[ubReceiveIndex++] = LL_I2C_ReceiveData8(I2C1);
    ubNbDataToReceive--;

    /* Disable Buffer Interrupts */
    LL_I2C_DisableIT_BUF(I2C1);
  }
  else if(ubNbDataToReceive == 2)
  {
    /* Generate Stop condition */
    LL_I2C_GenerateStopCondition(I2C1);

    /* Read character from Receive Data register.
    RXNE flag is cleared by reading data in RXDR register */
    aReceiveBuffer[ubReceiveIndex++] = LL_I2C_ReceiveData8(I2C1);
    ubNbDataToReceive--;

    /* Read character from shift register.
    RXNE flag is cleared by reading data in RXDR register */
    aReceiveBuffer[ubReceiveIndex++] = LL_I2C_ReceiveData8(I2C1);
    ubNbDataToReceive--;
  }
  else
  {
    if(ubNbDataToReceive > 0)
    {
      /* Read character from shift register.
      RXNE flag is cleared by reading data in RXDR register */
      aReceiveBuffer[ubReceiveIndex++] = LL_I2C_ReceiveData8(I2C2);
      
      /* Update ubNbDataToReceive variable */
      ubNbDataToReceive--;
    }
  }

  if(ubNbDataToReceive == 0)
  {
    /* (1) Disable I2C1 transfer event/error interrupts:
     *  - Disable Events Interrupt
     *  - Disable Error interrupts
     */
    LL_I2C_DisableIT_EVT(I2C1);
    LL_I2C_DisableIT_ERR(I2C1);

        LL_I2C_EnableIT_EVT(I2C1);
    LL_I2C_EnableIT_ERR(I2C1);
    /* 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();
            HAL_UART_Transmit_IT(&huart2,(uint8_t*)"#Data transfer is OK!$",strlen("#Data transfer is OK!$"));
            ubNbDataToTransmit     = sizeof(SLAVE_BYTE_TO_SEND);
            ubNbDataToReceive      = sizeof(SLAVE_BYTE_TO_SEND);
    }
    else
    {
      /* Call Error function */
      Error_Callback();
    }
  }
}

很容易理解，传输过程的结束是我添加HAL_UART function发送到串口发送完成。

但在此之后，它会再工作一次，然后停止。 我检查了示波器信号显示，第二次传输后 SCL 引脚变为低电平。 谢谢

Answer 1

好久没用LL了，但是用LL_I2C_DisableIT_EVT(I2C1); ?? 确保在下次传输之前再次启用它。

Answer 2

存在两个主设备无法通过 I2C 总线相互通信的情况。 因为主设备没有DEVICE_ADDRESS 。 主设备只能与从设备通信。