STM32FCAN发送出错是什么原因？

只看该作者 · 2017-5-18 15:39

本帖最后由 icaredbd 于 2017-5-18 15:42 编辑

在环回模式下可以成功，但是在正常工作模式下，没有成功发送数据。
CAN_TransmitStatus最终返回
CAN_TxStatus_Pending，请问大牛们是什么原因？
u8 CAN1_Send_Msg(u8* msg,u8 len)
{
  u8 mbox;
  u16 i=0;
  CanTxMsg TxMessage;
  TxMessage.StdId=0x12;
  TxMessage.ExtId=0x12;
  TxMessage.IDE=0;
  TxMessage.RTR=0;
  TxMessage.DLC=len;
  for(i=0;i<len;i++)
  TxMessage.Data=msg;
  mbox= CAN_Transmit(CAN1, &TxMessage);
  i=0;
  while((CAN_TransmitStatus(CAN1, mbox)==CAN_TxStatus_Failed)&&(i<0XFFF))i++;       //µÈ´ý·¢ËÍ½áÊø
  if(i>=0XFFF)return 1;
  return 0;
}

uint8_t CAN_Transmit(CAN_TypeDef* CANx, CanTxMsg* TxMessage)
{
  uint8_t transmit_mailbox = 0;
  /* Check the parameters */
  assert_param(IS_CAN_ALL_PERIPH(CANx));
  assert_param(IS_CAN_IDTYPE(TxMessage->IDE));
  assert_param(IS_CAN_RTR(TxMessage->RTR));
  assert_param(IS_CAN_DLC(TxMessage->DLC));

  /* Select one empty transmit mailbox */
  if ((CANx->TSR&CAN_TSR_TME0) == CAN_TSR_TME0)
  {
transmit_mailbox = 0;
  }
  else if ((CANx->TSR&CAN_TSR_TME1) == CAN_TSR_TME1)
  {
transmit_mailbox = 1;
  }
  else if ((CANx->TSR&CAN_TSR_TME2) == CAN_TSR_TME2)
  {
transmit_mailbox = 2;
  }
  else
  {
transmit_mailbox = CAN_TxStatus_NoMailBox;
  }

  if (transmit_mailbox != CAN_TxStatus_NoMailBox)
  {
/* Set up the Id */
CANx->sTxMailBox[transmit_mailbox].TIR &= TMIDxR_TXRQ;
if (TxMessage->IDE == CAN_Id_Standard)
{
   assert_param(IS_CAN_STDID(TxMessage->StdId));
   CANx->sTxMailBox[transmit_mailbox].TIR |= ((TxMessage->StdId << 21) | \
                                                TxMessage->RTR);
}
else
{
   assert_param(IS_CAN_EXTID(TxMessage->ExtId));
   CANx->sTxMailBox[transmit_mailbox].TIR |= ((TxMessage->ExtId << 3) | \
                                                TxMessage->IDE | \
                                                TxMessage->RTR);
}

/* Set up the DLC */
TxMessage->DLC &= (uint8_t)0x0000000F;
CANx->sTxMailBox[transmit_mailbox].TDTR &= (uint32_t)0xFFFFFFF0;
CANx->sTxMailBox[transmit_mailbox].TDTR |= TxMessage->DLC;

/* Set up the data field */
CANx->sTxMailBox[transmit_mailbox].TDLR = (((uint32_t)TxMessage->Data[3] << 24) |
                                          ((uint32_t)TxMessage->Data[2] << 16) |
                                          ((uint32_t)TxMessage->Data[1] << 8) |
                                          ((uint32_t)TxMessage->Data[0]));
CANx->sTxMailBox[transmit_mailbox].TDHR = (((uint32_t)TxMessage->Data[7] << 24) |
                                          ((uint32_t)TxMessage->Data[6] << 16) |
                                          ((uint32_t)TxMessage->Data[5] << 8) |
                                          ((uint32_t)TxMessage->Data[4]));
/* Request transmission */
CANx->sTxMailBox[transmit_mailbox].TIR |= TMIDxR_TXRQ;
  }
  return transmit_mailbox;
}

/**
  * @brief  Checks the transmission status of a CAN Frame.
  * @param  CANx: where x can be 1 or 2 to select the CAN peripheral.
  * @param  TransmitMailbox: the number of the mailbox that is used for transmission.
  * @retval CAN_TxStatus_Ok if the CAN driver transmits the message,
  *       CAN_TxStatus_Failed in an other case.
  */
uint8_t CAN_TransmitStatus(CAN_TypeDef* CANx, uint8_t TransmitMailbox)
{
  uint32_t state = 0;

  /* Check the parameters */
  assert_param(IS_CAN_ALL_PERIPH(CANx));
  assert_param(IS_CAN_TRANSMITMAILBOX(TransmitMailbox));

  switch (TransmitMailbox)
  {
case (CAN_TXMAILBOX_0):
   state = CANx->TSR &  (CAN_TSR_RQCP0 | CAN_TSR_TXOK0 | CAN_TSR_TME0);
   break;
case (CAN_TXMAILBOX_1):
   state = CANx->TSR &  (CAN_TSR_RQCP1 | CAN_TSR_TXOK1 | CAN_TSR_TME1);
   break;
case (CAN_TXMAILBOX_2):
   state = CANx->TSR &  (CAN_TSR_RQCP2 | CAN_TSR_TXOK2 | CAN_TSR_TME2);
   break;
default:
   state = CAN_TxStatus_Failed;
   break;
  }
  switch (state)
  {
   /* transmit pending  */
case (0x0): state = CAN_TxStatus_Pending;
   break;
   /* transmit failed  */
   case (CAN_TSR_RQCP0 | CAN_TSR_TME0): state = CAN_TxStatus_Failed;
   break;
   case (CAN_TSR_RQCP1 | CAN_TSR_TME1): state = CAN_TxStatus_Failed;
   break;
   case (CAN_TSR_RQCP2 | CAN_TSR_TME2): state = CAN_TxStatus_Failed;
   break;
   /* transmit succeeded  */
case (CAN_TSR_RQCP0 | CAN_TSR_TXOK0 | CAN_TSR_TME0):state = CAN_TxStatus_Ok;
   break;
case (CAN_TSR_RQCP1 | CAN_TSR_TXOK1 | CAN_TSR_TME1):state = CAN_TxStatus_Ok;
   break;
case (CAN_TSR_RQCP2 | CAN_TSR_TXOK2 | CAN_TSR_TME2):state = CAN_TxStatus_Ok;
   break;
default: state = CAN_TxStatus_Failed;
   break;
  }
  return (uint8_t) state;
}