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问 用示波器可以看见接收节点的RX0有信号，可接收缓冲器状态是空的，好像数据没有通过滤波。
发送节点的程序，另一个太大了，但初始化部分只是ACR不同（另一个为0xAB),并且那一个只是接收：

unsigned char xdata *SJA_BCANAdr;


unsigned char idata ControlDataIOF;
unsigned char idata ControlDataIDC[4];
unsigned char idata ControlDataBuf[8];
unsigned char idata StateDataIOF;
unsigned char idata StateDataIDC[4];
unsigned char idata StateDataBuf[8];


void main(void)
{  
   unsigned int time_delay;
   unsigned int i;
   
   P1_6=1;

    MCU_SJACS=0;

    SJA_INIT();


     StateDataIOF = 0x04;
       StateDataIDC[0] = 0xAB;
       StateDataIDC[1] = 0x00;
       StateDataIDC[2] = 0x00;
      StateDataIDC[3] = 0x00;
         
     for(i=0;i<4;i++)
         StateDataBuf[i]=i+34;

   while(1)
  {    
          
      BCAN_DATA_WRITE();
    for(time_delay=0;time_delay<50000;time_delay++)
        ;
   }
}



/*用于检测CAN控制器的接口是否正常*/
/*返回值：0 表示SJA1000接口正常  1  表示SJA1000与处理器接口不正常*/

bit BCAN_CREATE_COMMUNATION(void)
{
    SJA_BCANAdr=REG_TEST;  //访问测试寄存器
    *SJA_BCANAdr=0xaa;
    if(*SJA_BCANAdr==0xaa)
    {    
        *SJA_BCANAdr=0x3d;
        if(*SJA_BCANAdr==0x3d)
            return 0;
    }
    else
        return 1;
}


/*SJA1000 enter the reset model*/
/*返回值：0 表示SJA1000成功进入复位模式  1  表示SJA1000进入复位模式失败*/
bit BCAN_ENTER_RETMODEL(void)
{
    unsigned char TempData;
    SJA_BCANAdr=REG_MODE;
    TempData= *SJA_BCANAdr;
    *SJA_BCANAdr=(TempData|0x01);

    if((*SJA_BCANAdr&0x01)==1)
        return 0;
    else
        return 1;
}

/*SJA1000退出复位工作模式*/
/*返回值：0 表示SJA1000成功退出复位模式  1  表示SJA1000退出复位模式失败*/
bit BCAN_QUIT_RETMODEL(void)
{
    unsigned char TempData;
    SJA_BCANAdr=REG_MODE;
    TempData= *SJA_BCANAdr;
    *SJA_BCANAdr=(TempData&0xfe);
    
    if((*SJA_BCANAdr&0x01)==0)
        return 0;
    else
        return 1;
}


/*设置CAN控制器的波特率800k*/
/*返回值：0 波特率设置成功    1 波特率设置失败*/

bit BCAN_SET_BANDRATE(void)
{
    SJA_BCANAdr=REG_BTR0;
    *SJA_BCANAdr=ByteRate_100k_BTR0;
    if(*SJA_BCANAdr != ByteRate_100k_BTR0)
        return 1;
    
    SJA_BCANAdr=REG_BTR1;
    *SJA_BCANAdr=ByteRate_100k_BTR1;
    if(*SJA_BCANAdr != ByteRate_100k_BTR1)
        return 1;

    return 0;
}


/*设置CAN控制器的输出控制寄存器和时钟分频寄存器*/
/*返回值：0 设置成功    1 设置失败*/
void PCAN_SET_CDR(unsigned char Clock_Out)
{
    SJA_BCANAdr=REG_CDR;            //设置时钟分频寄存器
    *SJA_BCANAdr=Clock_Out;
}


bit PCAN_SET_OCR(unsigned char Out_Control)
{
    SJA_BCANAdr=REG_OCR;            //设置输出控制寄存器
    *SJA_BCANAdr=Out_Control;
    if(*SJA_BCANAdr!=Out_Control)
        return 1;

    return 0;
}

/*写数据 到SJA1000的发送缓冲区*/
/*返回值：0 发送成功    1 发送失败*/
void BCAN_DATA_WRITE(void)
{
     unsigned char  Length;              /* length of data frame*/
     unsigned char  i;
     unsigned char TempData;
     unsigned char   FF;                  /*FF =0x00 :标准CAN帧*/
                                          /*FF =0x80 :扩展CAN帧*/
    SJA_BCANAdr=REG_SR;
    TempData=*SJA_BCANAdr&0x04 ;

     if(TempData== 0x04)                /*发送缓冲区状态＝ 释放?*/
     {
         FF = StateDataIOF & 0x80;          /*取帧格式*/
         Length = StateDataIOF & 0x0F;      /*取数据长度代码*/
         if(Length > 0x08)
             Length = 0x08;
                                  

         SJA_BCANAdr=REG_TxBuffer0;
             *SJA_BCANAdr = StateDataIOF;
         SJA_BCANAdr=REG_TxBuffer1;
             *SJA_BCANAdr = StateDataIDC[0];
         SJA_BCANAdr=REG_TxBuffer2;
             *SJA_BCANAdr = StateDataIDC[1];
  
         if(FF)
         {
              SJA_BCANAdr=REG_TxBuffer3;
                   *SJA_BCANAdr = StateDataIDC[2];
              SJA_BCANAdr=REG_TxBuffer4;
                   *SJA_BCANAdr = StateDataIDC[3];
         }

         SJA_BCANAdr++;    
         for (i=0; i<Length; i++,SJA_BCANAdr++)  /* write data bytes */
         {
                 *SJA_BCANAdr = StateDataBuf[i];
         }


     /*置位发送请求位*/
         SJA_BCANAdr=REG_CMD;
          *SJA_BCANAdr = 0x03;      /*产生一次自接收性质的信息发送*/
     }
}


/*从SJA1000的发送缓冲区读数据*/
/*返回值：0 读成功    1 读失败*/
void BCAN_DATA_RECEIVE(void)
{
     unsigned char  Length;
     unsigned char  i;
     unsigned char  FF;

/* Check the CAN status register for received message */

     SJA_BCANAdr=REG_RxBuffer0;          /* set address pointer to receive buffer */
     ControlDataIOF = *SJA_BCANAdr;       /* read DSCR_0*/

     FF = ControlDataIOF & 0x80;
     Length = ControlDataIOF & 0x0F;

     if(Length > 0x08)
        Length = 0x08;

/* Read data bytes and write to buffer        */

     SJA_BCANAdr=REG_RxBuffer1;
     if(FF)
     {
        for(i=0; i<4; i++,SJA_BCANAdr++)
           ControlDataIDC[i] = *SJA_BCANAdr;
     }
     else
     {
        for(i=0; i<2; i++,SJA_BCANAdr++)
           ControlDataIDC[i] = *SJA_BCANAdr;
     }
     for (i=0; i < Length; i++,SJA_BCANAdr++)
        ControlDataBuf[i] = *SJA_BCANAdr;

     BCAN_CMD_PRG(RRB_CMD);
}    

/*执行SJA1000命令*/
/*返回值：0  命令执行成功       1    命令执行失败*/
bit BCAN_CMD_PRG(unsigned char cmd)    
{
   SJA_BCANAdr=REG_CMD;
   *SJA_BCANAdr=cmd;
   switch(cmd)
   {
      case TR_CMD:
           return 0;
           break;
      case AT_CMD:
           SJA_BCANAdr=REG_SR;
           if((*SJA_BCANAdr&0x20)==0)
           {
             return 0;
           }
           else
           {
             return 1;
           }
           break;
      case RRB_CMD:
           SJA_BCANAdr=REG_SR;
           if((*SJA_BCANAdr&0x01)==1)
           {
              return 1;
           }
           else
           {
              return 0;
           }
           break;
      case CDO_CMD:
           SJA_BCANAdr=REG_SR;
           if((*SJA_BCANAdr&0x02)==0)
           {
              return 0;
           }
           else
           {
              return 1;
           }
           break;
      case SRR_CMD:
           return 0;
           break;
      default:
           return  1;
           break;
    }
}



/*initialize the SJA1000*/
void SJA_INIT(void)
{  
    unsigned char i;
    for(i=0;i<125;i++)
        MCU_SJARST=0;                        //reset the SJA1000
    for(i=0;i<125;i++)
        MCU_SJARST=1;
    for(i=0;i<125;i++)
        ;

   if(BCAN_CREATE_COMMUNATION()==0)
   while(BCAN_ENTER_RETMODEL()!=0)
           ;
   
        PCAN_SET_CDR(0xC8);
        PCAN_SET_OCR(0xAA);

        BCAN_SET_BANDRATE();

         //SJA_BCANAdr=REG_RBSA;
        //    *SJA_BCANAdr=0x00;

        SJA_BCANAdr=REG_ACR0;
            *SJA_BCANAdr=0xAA;
        SJA_BCANAdr=REG_ACR1;
            *SJA_BCANAdr=0x00;
        SJA_BCANAdr=REG_ACR2;
            *SJA_BCANAdr=0x00;
        SJA_BCANAdr=REG_ACR3;
            *SJA_BCANAdr=0x00;

        SJA_BCANAdr=REG_AMR0;
            *SJA_BCANAdr=0xFF;
        SJA_BCANAdr=REG_AMR1;
            *SJA_BCANAdr=0xFF;
        SJA_BCANAdr=REG_AMR2;
            *SJA_BCANAdr=0xFF;
        SJA_BCANAdr=REG_AMR3;
            *SJA_BCANAdr=0xFF;

        SJA_BCANAdr=REG_MODE;
            i=*SJA_BCANAdr;
            *SJA_BCANAdr=i|0x08;


    while(BCAN_QUIT_RETMODEL()!=0);

    SJA_BCANAdr=REG_IR_ABLE;
        *SJA_BCANAdr=0x00;

}
答 1: re不要急,联网后也使用自收发方式发送,把验收屏蔽寄存器全部设置成0xff,看看能不能收到 答 2: 老兄，你先前的自收自发问题在哪？我的节点现在也是不能自收发