CAN通信是STM32中比较复杂的东西之一,它 的初始化主要分为两个部分,一个是CAN的初始化,一个是过滤器的初始化。自发自收只需要一个器件,CAN的模式选择回环(Loopback)模式,这种模式下发出的数据也会被CAN本身接收回来,只需要检查接收到的数据和发送的数据是否一样,就能测试发送是否成功。代码:- void CAN_Config(void)
- {
- CAN_InitTypeDef CAN_InitStructure;
- CAN_FilterInitTypeDef CAN_FilterInitStructure;
- RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1,ENABLE);
- CAN_DeInit(CAN1);
- CAN_StructInit(&CAN_InitStructure);
- CAN_InitStructure.CAN_TTCM = DISABLE;
- CAN_InitStructure.CAN_ABOM = DISABLE;
- CAN_InitStructure.CAN_AWUM = DISABLE;
- CAN_InitStructure.CAN_NART = DISABLE;
- CAN_InitStructure.CAN_RFLM = DISABLE;
- CAN_InitStructure.CAN_TXFP = DISABLE;
- CAN_InitStructure.CAN_Mode=CAN_Mode_LoopBack;//回环模式
- CAN_InitStructure.CAN_SJW=CAN_SJW_1tq;//1
- CAN_InitStructure.CAN_BS1=CAN_BS1_9tq;//9
- CAN_InitStructure.CAN_BS2=CAN_BS2_8tq;//8
- CAN_InitStructure.CAN_Prescaler=16;//16分频
- CAN_Init(CAN1,&CAN_InitStructure);
- CAN_FilterInitStructure.CAN_FilterNumber=0;
- CAN_FilterInitStructure.CAN_FilterMode=CAN_FilterMode_IdMask;//屏蔽模式
- CAN_FilterInitStructure.CAN_FilterScale=CAN_FilterScale_32bit;
- CAN_FilterInitStructure.CAN_FilterIdHigh = 0x0000;
- CAN_FilterInitStructure.CAN_FilterIdLow = 0x0000;
- CAN_FilterInitStructure.CAN_FilterMaskIdHigh = 0x0000;
- CAN_FilterInitStructure.CAN_FilterMaskIdLow = 0x0000;
- CAN_FilterInitStructure.CAN_FilterFIFOAssignment = CAN_FilterFIFO0;
- CAN_FilterInitStructure.CAN_FilterActivation=ENABLE;
- CAN_FilterInit(&CAN_FilterInitStructure);
- }
复制代码 配置完成,开始发送和接收:- void CAN_Test(void)
- {
- CanTxMsg TXmessage;
- CanRxMsg RXmessage;
- uint8_t TxMailbox=0;
- uint8_t ret=0;
- CAN_Config();
- TXmessage.StdId=0x123;//ID,标识符
- TXmessage.IDE=CAN_ID_STD;//标准ID
- TXmessage.RTR=CAN_RTR_DATA;//传送的是数据帧
- TXmessage.DLC=3;//数据个数。不能超过8个
- TXmessage.Data[0]=0x01;//传送的数据
- TXmessage.Data[1]=0x10;
- TXmessage.Data[2]=0xFF;
- TxMailbox=CAN_Transmit(CAN1,&TXmessage);//发送,返回的是当前邮箱号
- while(CAN_TransmitStatus(CAN1,TxMailbox) !=CANTXOK);//等待发送完成
- while(CAN_MessagePending(CAN1,CAN_FIFO0)<1);//查询接受状态位,看是否有信息(报文)到达
- RXmessage.StdId=0x00;//初始化接受结构体
- RXmessage.IDE=CAN_ID_STD;
- RXmessage.DLC=0;
- RXmessage.Data[0]=0;
- RXmessage.Data[1]=0;
- RXmessage.Data[2]=0;
- CAN_Receive(CAN1,CAN_FIFO0,&RXmessage);//接收信息(报文)
- //最后检查所接收到的数据每一个项和发送的是否一样,如果全部一样则发送成功,否则发送失败
- //设置标志位对结果进行保存,用串口打印或者LED显示不同的状态来表示发送接收情况
- }
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