/* Configure CAN1 pin: RX */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_CAN_RX;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
  GPIO_Init(GPIO_CAN, &GPIO_InitStructure);

/* Configure CAN1 pin: TX */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_CAN_TX;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init(GPIO_CAN, &GPIO_InitStructure);

GPIO_PinRemapConfig(GPIO_Remap_CAN , ENABLE);

/* Configure CAN2 pin: RX */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_CAN_RX_2;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
  GPIO_Init(GPIO_CAN_2, &GPIO_InitStructure);

/* Configure CAN2 pin: TX */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_CAN_TX_2;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init(GPIO_CAN_2, &GPIO_InitStructure);

GPIO_PinRemapConfig(GPIO_Remap_CAN_2 , ENABLE);
}

void CAN_Config(CAN_TypeDef* CANx, uint8_t CAN_FilterNumber)
{
  /* CAN register init */
  CAN_DeInit(CANx);
  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_3tq;
  CAN_InitStructure.CAN_BS2 = CAN_BS2_5tq;
  CAN_InitStructure.CAN_Prescaler = 4;//2
  CAN_Init(CANx, &CAN_InitStructure);

/* CAN filter init */
  CAN_FilterInitStructure.CAN_FilterNumber=CAN_FilterNumber;
  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=(CANx == CAN1? 0:1);
  CAN_FilterInitStructure.CAN_FilterActivation=ENABLE;
  CAN_FilterInit(CANx, &CAN_FilterInitStructure);

/* transmit */
  TxMessage.StdId = 0x321;
  TxMessage.ExtId = 0x01;
  TxMessage.RTR = CAN_RTR_DATA;
  TxMessage.IDE = CAN_ID_STD;
  TxMessage.DLC = 1;

}

CANx->MCR &= ~MCR_SLEEP;

/* Request initialisation */
  CANx->MCR |= MCR_INRQ ;

/* Wait the acknowledge */
  while (((CANx->MSR & MSR_INAK) != MSR_INAK) && (wait_ack != INAK_TimeOut))
  {
    wait_ack++;
  }

/* ...and check acknowledged */
  if ((CANx->MSR & MSR_INAK) != MSR_INAK)
  {
    InitStatus = CANINITFAILED;
  }
  else 
  {
    /* Set the time triggered communication mode */
    if (CAN_InitStruct->CAN_TTCM == ENABLE)
    {
      CANx->MCR |= MCR_TTCM;
    }
    else
    {
      CANx->MCR &= ~MCR_TTCM;
    }

/* Set the automatic bus-off management */
    if (CAN_InitStruct->CAN_ABOM == ENABLE)
    {
      CANx->MCR |= MCR_ABOM;
    }
    else
    {
      CANx->MCR &= ~MCR_ABOM;
    }

/* Set the automatic wake-up mode */
    if (CAN_InitStruct->CAN_AWUM == ENABLE)
    {
      CANx->MCR |= MCR_AWUM;
    }
    else
    {
      CANx->MCR &= ~MCR_AWUM;
    }

/* Set the no automatic retransmission */
    if (CAN_InitStruct->CAN_NART == ENABLE)
    {
      CANx->MCR |= MCR_NART;
    }
    else
    {
      CANx->MCR &= ~MCR_NART;
    }

/* Set the receive FIFO locked mode */
    if (CAN_InitStruct->CAN_RFLM == ENABLE)
    {
      CANx->MCR |= MCR_RFLM;
    }
    else
    {
      CANx->MCR &= ~MCR_RFLM;
    }

/* Set the transmit FIFO priority */
    if (CAN_InitStruct->CAN_TXFP == ENABLE)
    {
      CANx->MCR |= MCR_TXFP;
    }
    else
    {
      CANx->MCR &= ~MCR_TXFP;
    }

/* Set the bit timing register */
    CANx->BTR = (uint32_t)((uint32_t)CAN_InitStruct->CAN_Mode << 30) | ((uint32_t)CAN_InitStruct->CAN_SJW << 24) |
               ((uint32_t)CAN_InitStruct->CAN_BS1 << 16) | ((uint32_t)CAN_InitStruct->CAN_BS2 << 20) |
               ((uint32_t)CAN_InitStruct->CAN_Prescaler - 1);

/* Request leave initialisation */
    CANx->MCR &= ~MCR_INRQ;

/* Wait the acknowledge */
   wait_ack = 0x00;

while (((CANx->MSR & MSR_INAK) == MSR_INAK) && (wait_ack != INAK_TimeOut))
   {
     wait_ack++;
   }

/* ...and check acknowledged */
    if ((CANx->MSR & MSR_INAK) == MSR_INAK)
    {
      InitStatus = CANINITFAILED;
    }
    else
    {
      InitStatus = CANINITOK ;
    }
  }

/* At this step, return the status of initialization */
  return InitStatus;

就是死在了   while (((CANx->MSR & MSR_INAK) == MSR_INAK) && (wait_ack != INAK_TimeOut))
   {
     wait_ack++;
   }手册说是到这个地方是硬件自动对CAN_MSR_INAK位自动清零，但是就是一直没出现，希望各位大神赐教啊！！！！！