1、打开STM32 CAN系统工作时钟
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE); RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE);
2、开放系统中断，根据实际情况选择
NVIC_InitStructure.NVIC_IRQChannel = USB_LP_CAN1_RX0_IRQn; NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0; NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; NVIC_Init(&NVIC_InitStructure); // NVIC_InitStructure.NVIC_IRQChannel = CAN1_RX1_IRQn; // NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 5; // NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; // NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; // NVIC_Init(&NVIC_InitStructure);
//NVIC_InitStructure.NVIC_IRQChannel = CAN1_SCE_IRQn; //NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 3; //NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; //NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; //NVIC_Init(&NVIC_InitStructure); // NVIC_InitStructure.NVIC_IRQChannel = USB_HP_CAN1_TX_IRQn; // NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 4; // NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; // NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; // NVIC_Init(&NVIC_InitStructure);
3、端口配置
//初始化MCU_CAN_RXD---PA11 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU; GPIO_Init(GPIOA, &GPIO_InitStructure);
//初始化MCU_CAN_TXD---PA12 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12; GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; GPIO_Init(GPIOA, &GPIO_InitStructure);
4、CAN初始化
void CAN_Configuration(void) { CAN_InitTypeDef CAN_InitStructure; CAN_FilterInitTypeDef CAN_FilterInitStructure;
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 = ENABLE; CAN_InitStructure.CAN_RFLM = DISABLE; CAN_InitStructure.CAN_TXFP = ENABLE; //CAN_InitStructure.CAN_Mode = CAN_Mode_LoopBack; CAN_InitStructure.CAN_Mode = CAN_Mode_Normal; CAN_InitStructure.CAN_SJW = CAN_SJW_1tq; CAN_InitStructure.CAN_BS1 = CAN_BS1_9tq; CAN_InitStructure.CAN_BS2 = CAN_BS2_8tq; CAN_InitStructure.CAN_Prescaler = 200;
//此处Tseg1+1 = CAN_BS1_8tp
if (CAN_Init(CAN1,&CAN_InitStructure) == CANINITFAILED) { } CAN_FilterInitStructure.CAN_FilterNumber=0; CAN_FilterInitStructure.CAN_FilterMode=CAN_FilterMode_IdMask; 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=0; CAN_FilterInitStructure.CAN_FilterActivation=ENABLE; CAN_FilterInit(&CAN_FilterInitStructure); CAN_FilterInitStructure.CAN_FilterNumber=1; CAN_FilterInitStructure.CAN_FilterMode=CAN_FilterMode_IdMask; 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=1; //CAN_FilterInitStructure.CAN_FilterActivation=ENABLE; CAN_FilterInit(&CAN_FilterInitStructure); CAN_ITConfig(CAN1,CAN_IT_FMP0, ENABLE); CAN_ITConfig(CAN2, CAN_IT_TME, ENABLE); //打开发送中断 CAN_ITConfig(CAN2, CAN_IT_FMP1, ENABLE); //打开接收中断 CAN_ITConfig(CAN2, CAN_IT_EWG|CAN_IT_EPV|CAN_IT_BOF|CAN_IT_LEC|CAN_IT_ERR, ENABLE);//打开错误中断 //CAN_ITConfig(CAN1,CAN_IT_FMP0, ENABLE); //FIFO0 消息挂号中断屏蔽 //CAN_ITConfig(CAN1,CAN_IT_TME, ENABLE); //发送邮箱空中断屏蔽 //CAN_ITConfig(CAN1,CAN_IT_BOF, ENABLE); //离线中断允许 }
5、发送数据函数
void CanWriteData(uint16_t CanAddress,uint8_t SendData[8]) { CanTxMsg TxMessage; //定义数据结构类型变量 u8 TransmitMailbox = 0; u16 i = 0; TxMessage.StdId = CanAddress; TxMessage.ExtId=0x00; //tempId 为接受板地址，应用过程中要左移13位 TxMessage.IDE=CAN_ID_STD;//使用标准id TxMessage.RTR=CAN_RTR_DATA;//发送数据帧 TxMessage.DLC= 8; //设置发送数据的长度 TxMessage.Data[0] = SendData[0];//赋值待发送 TxMessage.Data[1] = SendData[1];//赋值待发送 TxMessage.Data[2] = SendData[2];//赋值待发送 TxMessage.Data[3] = SendData[3];//赋值待发送 TxMessage.Data[4] = SendData[4];//赋值待发送 TxMessage.Data[5] = SendData[5];//赋值待发送 TxMessage.Data[6] = SendData[6];//赋值待发送 TxMessage.Data[7] = SendData[7];//赋值待发送 TransmitMailbox = CAN_Transmit(CAN1,&TxMessage);//开始发送数据 i = 0; //通过检查CANTXOK位来确认发送是否成功 while((CAN_TransmitStatus(CAN1,TransmitMailbox) != CANTXOK) && (i != 0xFF)) { i++; } i = 0; while((CAN_MessagePending(CAN1,CAN_FIFO0) < 1) && (i != 0xFF)) //返回被挂起的报文量是否为0 { i++; } }
void SEND_CAN_TQ_COMMAND(u8 device_add,u8 GFB_flag,u8 TQ_A_flag,u8 TQ_B_flag) { u16 Send_add,num; u8 Send_Data[8]; if(device_add == 0) { switch(GFB_flag) { case 90: if(TQ_A_flag == 0x22) { TQ_CON_A = 1; TQ_CON_B = 1; TQ_CON_C = 1; JDQ_A_Flag = 0x07; Net_Node_CapA[0] = Net_Node_CapA[0]|0x07; } else if(TQ_A_flag == 0x11) { TQ_CON_A = 0; TQ_CON_B = 0; TQ_CON_C = 0; JDQ_A_Flag = 0x00; Net_Node_CapA[0] = Net_Node_CapA[0]&0x00; } if(TQ_B_flag == 0x22) { TQ_CON_2A = 1; TQ_CON_2B = 1; TQ_CON_2C = 1; JDQ_B_Flag = 0x07; Net_Node_CapB[0] = Net_Node_CapB[0]|0x07; } else if(TQ_B_flag == 0x11) { TQ_CON_2A = 0; TQ_CON_2B = 0; TQ_CON_2C = 0; JDQ_B_Flag = 0x00; Net_Node_CapB[0] = Net_Node_CapB[0]&0x00; } break; case 91: if(TQ_A_flag == 0x22) { TQ_CON_A = 1; JDQ_A_Flag |= 0x04; Net_Node_CapA[0] = Net_Node_CapA[0]|0x04; } else if(TQ_A_flag == 0x11) { TQ_CON_A = 0; JDQ_A_Flag &= 0xFB; Net_Node_CapA[0] = Net_Node_CapA[0]&0xFB; } break; case 92: if(TQ_A_flag == 0x22) { TQ_CON_A = 1; JDQ_A_Flag |= 0x02; Net_Node_CapA[0] = Net_Node_CapA[0]|0x02; } else if(TQ_A_flag == 0x11) { TQ_CON_A = 0; JDQ_A_Flag &= 0xFD; Net_Node_CapA[0] = Net_Node_CapA[0]&0xFD; } break; case 93: if(TQ_A_flag == 0x22) { TQ_CON_A = 1; JDQ_A_Flag |= 0x01; Net_Node_CapA[0] = Net_Node_CapA[0]|0x01; } else if(TQ_A_flag == 0x11) { TQ_CON_A = 0; JDQ_A_Flag &= 0xFE; Net_Node_CapA[0] = Net_Node_CapA[0]&0xFE; } break; } } else { Send_add = 0x100 + device_add; Send_Data[0] = 0x55; Send_Data[1] = 0x01; Send_Data[2] = device_add; //从机地址 Send_Data[3] = GFB_flag; //共补投入控制指令 Send_Data[4] = TQ_A_flag; Send_Data[5] = TQ_B_flag; num = Send_Data[1] + Send_Data[2] + Send_Data[3] + Send_Data[4] + Send_Data[5]; Send_Data[6] = num&0xFF; Send_Data[7] = 0xAA; CanWriteData(Send_add,Send_Data); switch(GFB_flag) { case 90: if(TQ_A_flag == 0x22) { Net_Node_CapA[device_add] = Net_Node_CapA[device_add]|0x07; } else if(TQ_A_flag == 0x11) { Net_Node_CapA[device_add] = Net_Node_CapA[device_add]&0x00; } if(TQ_B_flag == 0x22) { Net_Node_CapB[device_add] = Net_Node_CapB[device_add]|0x07; } else if(TQ_B_flag == 0x11) { Net_Node_CapB[device_add] = Net_Node_CapB[device_add]&0x00; } break; case 91: if(TQ_A_flag == 0x22) { Net_Node_CapA[device_add] = Net_Node_CapA[device_add]|0x04; } else if(TQ_A_flag == 0x11) { Net_Node_CapA[device_add] = Net_Node_CapA[device_add]&0xFB; } break; case 92: if(TQ_A_flag == 0x22) { Net_Node_CapA[device_add] = Net_Node_CapA[device_add]|0x02; } else if(TQ_A_flag == 0x11) { Net_Node_CapA[device_add] = Net_Node_CapA[device_add]&0xFD; } break; case 93: if(TQ_A_flag == 0x22) { Net_Node_CapA[device_add] = Net_Node_CapA[device_add]|0x01; } else if(TQ_A_flag == 0x11) { Net_Node_CapA[device_add] = Net_Node_CapA[device_add]&0xFE; } break; } } }
6、中断接收函数
void USB_LP_CAN1_RX0_IRQHandler(void) //CAN中断函数 { CanRxMsg RxMessage; u8 i; RxMessage.StdId=0x00; //初始化接收数据池 RxMessage.ExtId=0x00; RxMessage.IDE=0; RxMessage.DLC=0; RxMessage.FMI=0; RxMessage.Data[0]=0x00; RxMessage.Data[1]=0x00; RxMessage.Data[2]=0x00; RxMessage.Data[3]=0x00; RxMessage.Data[4]=0x00; RxMessage.Data[5]=0x00; RxMessage.Data[6]=0x00; RxMessage.Data[7]=0x00; //while(CAN_IT_FF0==0); for(i=0;i<8;i++) { if(Can_Receive_Flag[i] == 0) { if(CAN_IT_FF0 > 0) { CAN_Receive(CAN1, CAN_FIFO0, &RxMessage); //从CAN1口缓冲器FIFO 0接收报文到 RxMessage CAN_Receive_data[i][0] = (RxMessage.StdId>>8)&0xff; CAN_Receive_data[i][1] = (RxMessage.StdId)&0xff; CAN_Receive_data[i][2] = RxMessage.Data[0]; CAN_Receive_data[i][3] = RxMessage.Data[1]; CAN_Receive_data[i][4] = RxMessage.Data[2]; CAN_Receive_data[i][5] = RxMessage.Data[3]; CAN_Receive_data[i][6] = RxMessage.Data[4]; CAN_Receive_data[i][7] = RxMessage.Data[5]; CAN_Receive_data[i][8] = RxMessage.Data[6]; CAN_Receive_data[i][9] = RxMessage.Data[7]; CAN_Receive_data[i][10] = 0xff; Can_Receive_Flag[i] = 1; break; } if(CAN_IT_FF1 > 0) { CAN_Receive(CAN1, CAN_FIFO1, &RxMessage); //从CAN1口缓冲器FIFO 0接收报文到 RxMessage CAN_Receive_data[i][0] = (RxMessage.StdId>>8)&0xff; CAN_Receive_data[i][1] = (RxMessage.StdId)&0xff; CAN_Receive_data[i][2] = RxMessage.Data[0]; CAN_Receive_data[i][3] = RxMessage.Data[1]; CAN_Receive_data[i][4] = RxMessage.Data[2]; CAN_Receive_data[i][5] = RxMessage.Data[3]; CAN_Receive_data[i][6] = RxMessage.Data[4]; CAN_Receive_data[i][7] = RxMessage.Data[5]; CAN_Receive_data[i][8] = RxMessage.Data[6]; CAN_Receive_data[i][9] = RxMessage.Data[7]; CAN_Receive_data[i][10] = 0xff; Can_Receive_Flag[i] = 1; break; } } } CAN_ClearITPendingBit(CAN1, CAN_IT_FMP0); } 附录：
接收与发送函数为目前项目中测试程序代码，根据实际情况可调整。
原帖网址：http://blog.sina.com.cn/s/blog_56e19aa70101f44t.html
