c8051f040中can控制器的应用2.doc

3.（03424a）C8051F040中的CAN控制器应用P55CAN通信部分源程序如下：. /* 报文对象初始化程序清空所有报文对象，因为有些MESSAGE OBJECT不用但要初始化将不使用的message object的MsgVal都复位 */void clear_msg_objects (void) unsigned char i; SFRPAGE = CAN0_PAGE; /*指向CAN0页面：0X01 */ CAN0ADR = IF1CMDMSK; /* 指向命令屏蔽寄存器1*/ CAN0DATL = 0xFF; /*设置为“写”，通过IFX接口寄存器写目标对象*/ for (i=1;i33;i+) CAN0ADR = IF1ARB2; CAN0DAT=0X0000; CAN0DAT=0X0000; CAN0ADR = IF1CMDRQST; / Write blank (reset) IF registers to each msg obj CAN0DATL = i; /* Start CANCAN_CLK=8MHZ,BRP=2,BIT RATE=5MBit/s，bus length=100m 1M=0X163BIF1为发送操作接口寄存器，IF2为接收操作接口寄存器 100K=0X34C5*/void start_CAN (void) SFRPAGE = CAN0_PAGE; CAN0CN |= 0x41; /*将CCE和Init置“1”开始初始化*/ CAN0ADR = BITREG; /*指向位定时寄存器进行配置*/ CAN0DAT = 0x2301; /*位率为500k/s*/ CAN0CN |= 0x06; /*允许全局中断，IE和SIE置位*/ CAN0CN &= 0x41; /*清楚CCE和INIT位，启动CAN状态机制*/ /* 初始化发送对象 用四个message object,IF1用来发送报文 */void init_msg_object_TX (char MsgNum) SFRPAGE = CAN0_PAGE; CAN0ADR = IF1CMDMSK; /*指向IF1命令屏蔽寄存器*/ CAN0DAT = 0x00B8; /*设置为写操作，除了ID的mask和数据位不能改变，其它都可以变化*/ switch(MsgNum) case 1: /*第一个目标对象的ID=0*/ CAN0ADR = IF1ARB1; /*指向仲裁寄存器1*/ CAN0DAT = 0x0000; CAN0DAT = 0xA000; /*使用标准帧*/ CAN0ADR = IF1MSK1; /*设置相应的屏蔽寄存器*/ CAN0DAT = 0x0000; CAN0DAT = 0x0000;break; case 2: /*第2个目标对象的ID=1*/ CAN0ADR = IF1ARB1; CAN0DAT = 0x0000; CAN0DAT = 0xA004; CAN0ADR = IF1MSK1; CAN0DAT = 0x0000; CAN0DAT = 0x0004;break; case 3: /*第3个目标对象的ID=2*/ CAN0ADR = IF1ARB1; CAN0DAT = 0x0000; CAN0DAT = 0xA008; CAN0ADR = IF1MSK1; CAN0DAT = 0x0000; CAN0DAT = 0x0008;break; case 4: /*第4个目标对象的ID=3*/ CAN0ADR = IF1ARB1; CAN0DAT = 0x0000; CAN0DAT = 0xA00C; CAN0ADR = IF1MSK1; CAN0DAT = 0x0000; CAN0DAT = 0x000C;break; case 5: /*第5个目标对象的ID=4*/ CAN0ADR = IF1ARB1; CAN0DAT = 0x0000; CAN0DAT = 0xA010; CAN0ADR = IF1MSK1; CAN0DAT = 0x0000; CAN0DAT = 0x0010;break; CAN0ADR = IF1MSGC; /*设置报文控制寄存器：DLC=8,远程帧允许，中断允许*/ CAN0DAT = 0X2208; CAN0ADR = IF1CMDRQST; /*指向命令请求寄存器*/ CAN0DAT = MsgNum; /*向此寄存器中写入目标对象编号，对此对象进行设置*/ /* 初始化接收对象 用的四个message object,IF2用来接收报文 */void init_msg_object_RX (char MsgNum) SFRPAGE = CAN0_PAGE; CAN0ADR = IF2CMDMSK; /*指向命令屏蔽寄存器2*/ CAN0DAT = 0x00B8; switch(MsgNum) case 6: /*第6个对象用来接收数据ID=5*/ CAN0ADR = IF2ARB1; CAN0DAT = 0x0000; CAN0DAT = 0x8014; CAN0ADR = IF2MSK1; CAN0DAT = 0x0000; CAN0DAT = 0xC014; ;break; case 7: /*第7个对象用来接收数据ID=6*/ CAN0ADR = IF2ARB1; CAN0DAT = 0x0000; CAN0DAT = 0x8018; CAN0ADR = IF2MSK1; CAN0DAT = 0x0000; CAN0DAT = 0xC018; ;break; case 8: /*第8个对象用来接收数据ID=7*/ CAN0ADR = IF2ARB1; CAN0DAT = 0x0000; CAN0DAT = 0x801C; CAN0ADR = IF2MSK1; CAN0DAT = 0x0000; CAN0DAT = 0xC01C; ;break; case 9: /*第9个对象用来接收数据ID=8*/ CAN0ADR = IF2ARB1; CAN0DAT = 0x0000; CAN0DAT = 0x8020; CAN0ADR = IF2MSK1; CAN0DAT = 0x0000; CAN0DAT = 0xC020; ;break;case 10: /*第10个对象用来接收数据ID=9*/ CAN0ADR = IF2ARB1; CAN0DAT = 0x0000; CAN0DAT = 0x8024; CAN0ADR = IF2MSK1; CAN0DAT = 0x0000; CAN0DAT = 0xC024; ;break; CAN0ADR = IF2MSGC; /*设置报文控制寄存器：中断允许、DLC=8*/ CAN0DAT = 0x1488; CAN0ADR = IF2CMDRQST; CAN0DATL = MsgNum; /* 数据发送部分CAN数据更新，由定时器2产生中断 */void transmit_ISR(void) interrupt 5TF2=0; transmit_temp_value (); void transmit_temp_value (void)char i; for(i=0;i=4;i+) transmit_FIFO_block (i); void transmit_FIFO_block (char id_value) switch(id_value) case 0: transmit_message (0X01); break; case 1: transmit_message (0X02); break; case 2: transmit_message (0X03); break; case 3: transmit_message (0X04); break; case 4: transmit_message (0X05); break; void transmit_message (char MsgNum) uchar k=0,l=4; uchar m=8,n=12,h=16; uchar i; SFRPAGE = CAN0_PAGE; CAN0ADR = IF1CMDMSK; CAN0DAT = 0X0083; CAN0ADR = IF1ARB2; switch(MsgNum) case 0X01: CAN0DATH |= 0x80;CAN0ADR = IF1DATA1; for(i=0;i4;i+) CAN0DAT = can_tempk; k+; break;case 0X02: CAN0DATH |= 0x81; CAN0ADR = IF1DATA1; for(i=0;i4;i+) CAN0DAT = can_templ; l+; break;case 0X03: CAN0DATH |= 0x82; CAN0ADR = IF1DATA1; for(i=0;i4;i+)CAN0DAT = can_tempm; m+; break;case 0X04: CAN0DATH |= 0x83; CAN0ADR = IF1DATA1; for(i=0;i4;i+) CAN0DAT = can_tempn; n+; break;case 0X05: CAN0DATH |= 0x84; CAN0ADR = IF1DATA1; for(i=0;i4;i+) CAN0DAT = can_temph; h+; break; CAN0ADR = IF1CMDRQST; CAN0DATL = MsgNum; /* 数据接收函数 */void receive_data(void) char k,l,i; char m,n,h; SFRPAGE = CAN0_PAGE; CAN0ADR = IF2CMDMSK; CAN0DAT = 0x003F; for(i=6;i11;i+) CAN0ADR = IF2CMDRQST; CAN0DATL = i; switch(i) case 6: CAN0ADR = IF2DATA1; /* 指向数据场的第一个字节*/ for(k=0;k4;k+) /*读取4个字节的数据*/ can_RXk= CAN0DAT; ;break; case 7: CAN0ADR = IF2DATA1; for(l=4;l8;l+) can_RXl= CAN0DAT; ;break; case 8: CAN0ADR = IF2DATA1; for(m=8;m12;m+) can_RXm= CAN0DAT; ;break; case 9: CAN0ADR = IF2DATA1; for(n=12;n16;n+) can_RXn= CAN0DAT; ;break; case 10: CAN0ADR = IF2DATA1; for(h=16;h20;h+) can_RXh= CAN0DAT; ;break; /* CAN中断程序 */void CAN_ISR (void) interrupt 19 int status= CAN0STA; if (status&0x10) != 0) /* RxOk 置位,中断由接收引起*/ CAN0STA = (CAN0STA