请求香帮主关于CAN无法通讯的问题

只看该作者 · 2009-9-25 15:01

目前在一款终端上调试CAN通讯出现无**常通讯的问题（在用J-LINK调试的时候比较正常），重新上电10次大概只有一两次能够正常，但相同的程序用在另一款终端上CAN通讯很正常（相同的硬件，不同的PCB）。这个问题已经困扰好几天了，到现在还没有解决。实在没撤，还请各位高手帮忙分析下问题可能出在哪里！！！
STM32F103VE，CAN接收器采用CTM1050T（5V，与STM32直连，期间也试过用CTM8251AT，3.3V的，情况一样）,CAN调试器采用CAN232MB，两端均接有120欧电阻。无**常通讯时各寄存器值如下：
MSR寄存器（低位在前）00 0C 00 00：RX--1 SAMP--1
TSR  08 00 00 82 TEER0--1
ESR:  57 00 F8 00 TEC--F8 LEC--5显性位错误  BOFF--1 EPVF--1 EWGF--1
                     IER:  02 00 00 00 FMPIE0--1
用示波器测量CANL CANH，看到的都是低电平(隐性位)，没看到有显性位，用CAN232MB可以往总线上成功发送数据，在CAN_RX上也能检测到波形。

只看该作者 · 2009-9-25 15:02

以下为CAN初始化程序
void CAN_Configuration(void)
{
  GPIO_InitTypeDef GPIO_InitStructure;
  CAN_InitTypeDef       CAN_InitStructure;
  CAN_FilterInitTypeDef  CAN_FilterInitStructure;
  RCC_ClocksTypeDef RCC_ClocksStatus;


//Configure CAN pin: RX
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
  GPIO_Init(GPIOA, &GPIO_InitStructure);

  //Configure CAN pin: TX
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_12;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_Init(GPIOA, &GPIO_InitStructure);

  RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE);

RCC_GetClocksFreq(&RCC_ClocksStatus);
CAN_DeInit(CAN1);
  CAN_StructInit(&CAN_InitStructure);
// CAN cell init
  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_Normal;
  CAN_InitStructure.CAN_SJW=CAN_SJW_1tq;
  CAN_InitStructure.CAN_BS1=CAN_BS1_13tq;
  CAN_InitStructure.CAN_BS2=CAN_BS2_2tq;
  CAN_InitStructure.CAN_Prescaler=RCC_ClocksStatus.PCLK1_Frequency/(16*250000);    //波特率计算，16M/（1+8+7）/4=250k
  if(!CAN_Init(CAN1, &CAN_InitStructure))
  {
    //CAN初始化失败
    Can_Structure.Init_Fail_Flag = true;
    return;
  }
  /*这里注意的是采用点的位置,也就时BS1,BS2的设置问题，是CANopen协议中推荐的设置。
  1Mbps速率下，采用点的位置在6tq位置处，BS1=5,BS2=2
  500kbps速率下，采用点的位置在8tq位置处，BS1=7,BS2=3
  250kbps速率下，采用点的位置在14tq位置处，BS1=13,BS2=2
  125k,100k,50k,20k,10k的采用点位置与250K相同。*/
  /* CAN filter init */
/* 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 filter init
  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=CAN_FIFO0;
  CAN_FilterInitStructure.CAN_FilterActivation=ENABLE;
  CAN_FilterInit(&CAN_FilterInitStructure);
  CAN_ITConfig(CAN1, CAN_IT_FMP0, ENABLE);

}

只看该作者 · 2009-9-25 15:04

void CAN_SendDataToMeter(void)
{
static u8 Can_Send_FAIL_Cnt = 0x00;
u16 i;
CanTxMsg TxMessage;
u8 TransmitMailbox = 0;

if((Can_Send_FAIL_Cnt >= 30)&&(Can_Structure.Init_Fail_Flag))
{
Can_Send_FAIL_Cnt = 0x00;
Can_Structure.Init_Fail_Flag = false;
ON_CAN_PWR();
CAN_Configuration();
return;

}
//使用扩展ID发送
  TxMessage.StdId=0x00;
  TxMessage.ExtId=0x501;
  TxMessage.IDE=CAN_ID_EXT;
  TxMessage.RTR=CAN_RTR_DATA;
  TxMessage.DLC=8;
  MemoryCpy(TxMessage.Data, CAN_Send_DataBuff, 8);
  TransmitMailbox = CAN_Transmit(CAN1, &TxMessage);
  i = 0;
  while((CAN_TransmitStatus(CAN1, TransmitMailbox) != CANTXOK) && (i < 0xFF))
  {
i++;
  }

  if(i >= 0xFF)
    Can_Send_FAIL_Cnt ++;
else
Can_Send_FAIL_Cnt = 0x00;
}