实现stm32f103的CAN收发程式

以下是一个基本的STM32F103的CAN收发程序，可以实现CAN的基本收发功能。

首先，需要在STM32F103上初始化CAN控制器。这可以通过以下函数实现：

void CAN_Init(void)
{
  CAN_InitTypeDef CAN_InitStruct;
  CAN_FilterInitTypeDef CAN_FilterInitStruct;

  RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE);

  CAN_InitStruct.CAN_TTCM = DISABLE;
  CAN_InitStruct.CAN_ABOM = DISABLE;
  CAN_InitStruct.CAN_AWUM = DISABLE;
  CAN_InitStruct.CAN_NART = ENABLE;
  CAN_InitStruct.CAN_RFLM = DISABLE;
  CAN_InitStruct.CAN_TXFP = ENABLE;
  CAN_InitStruct.CAN_Mode = CAN_Mode_Normal;
  CAN_InitStruct.CAN_SJW = CAN_SJW_1tq;
  CAN_InitStruct.CAN_BS1 = CAN_BS1_8tq;
  CAN_InitStruct.CAN_BS2 = CAN_BS2_7tq;
  CAN_InitStruct.CAN_Prescaler = 9;

  CAN_Init(CAN1, &CAN_InitStruct);

  CAN_FilterInitStruct.CAN_FilterNumber = 0;
  CAN_FilterInitStruct.CAN_FilterMode = CAN_FilterMode_IdMask;
  CAN_FilterInitStruct.CAN_FilterScale = CAN_FilterScale_32bit;
  CAN_FilterInitStruct.CAN_FilterIdHigh = 0x0000;
  CAN_FilterInitStruct.CAN_FilterIdLow = 0x0000;
  CAN_FilterInitStruct.CAN_FilterMaskIdHigh = 0x0000;
  CAN_FilterInitStruct.CAN_FilterMaskIdLow = 0x0000;
  CAN_FilterInitStruct.CAN_FilterFIFOAssignment = 0;
  CAN_FilterInitStruct.CAN_FilterActivation = ENABLE;

  CAN_FilterInit(&CAN_FilterInitStruct);
}

接下来，可以使用以下代码发送CAN消息：

void CAN_Send(uint32_t id, uint8_t* data, uint8_t len)
{
  CanTxMsg TxMessage;

  TxMessage.StdId = id;
  TxMessage.ExtId = id;
  TxMessage.RTR = CAN_RTR_DATA;
  TxMessage.IDE = CAN_ID_STD;
  TxMessage.DLC = len;
  memcpy(TxMessage.Data, data, len);

  CAN_Transmit(CAN1, &TxMessage);
}

其中，id是CAN消息的ID，data是消息的数据，len是数据的长度。这将创建一个CAN消息并将其发送到CAN总线上。

最后，可以使用以下代码来接收CAN消息：

void CAN_Receive(void)
{
  CanRxMsg RxMessage;

  if (CAN_MessagePending(CAN1, CAN_FIFO0) > 0)
  {
    CAN_Receive(CAN1, CAN_FIFO0, &RxMessage);
    // 在这里对接收到的CAN消息进行处理
  }
}

这将检查是否有待处理的CAN消息，并将其存储在RxMessage变量中。然后，您可以在代码中对接收到的CAN消息进行处理。

请注意，这只是一个基本的STM32F103的CAN收发程序。实际应用中可能需要更多的错误处理和状态检查。