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CAN回环模式测试代码
#include "stm32f10x.h"
#include "delay.h"

typedef enum {FAILED = 0, PASSED = !FAILED} TestStatus;
vu32 ret; /* for return of the interrupt handling */
volatile TestStatus TestRx;
ErrorStatus HSEStartUpStatus;

TestStatus CAN_Polling(void);
TestStatus CAN_Interrupt(void);

void GPIO_Configuration(void)
{
 GPIO_InitTypeDef GPIO_InitStructure;

   /* Configure PE.02, PE.03, PE.04 and PE.05 LED as Output push-pull */
   
   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2 | GPIO_Pin_3 | GPIO_Pin_4 | GPIO_Pin_5;
   GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
   GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
   GPIO_Init(GPIOE, &GPIO_InitStructure);

   /* Configure CAN pin: RX PB8*/
   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0;
   GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
   GPIO_Init(GPIOD, &GPIO_InitStructure);
 
   /* Configure CAN pin: TX PB9*/
   GPIO_InitStructure.GPIO_Pin = GPIO_Pin_1;
   GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
   GPIO_Init(GPIOD, &GPIO_InitStructure);

 GPIO_PinRemapConfig(GPIO_Remap2_CAN1, ENABLE );    //重影射CAN IO脚到 PB8，PB9

 GPIO_SetBits(GPIOE, GPIO_Pin_2);
 GPIO_SetBits(GPIOE, GPIO_Pin_3);
 GPIO_SetBits(GPIOE, GPIO_Pin_5);
 GPIO_SetBits(GPIOE, GPIO_Pin_4);
}

//系统中断管理
void NVIC_Configuration(void)
{
 NVIC_InitTypeDef NVIC_InitStructure;

   /* Configure the NVIC Preemption Priority Bits */ 
   NVIC_PriorityGroupConfig(NVIC_PriorityGroup_0);

 #ifdef  VECT_TAB_RAM 
   /* Set the Vector Table base location at 0x20000000 */
   NVIC_SetVectorTable(NVIC_VectTab_RAM, 0x0);
 #else  /* VECT_TAB_FLASH  */
   /* Set the Vector Table base location at 0x08000000 */
   NVIC_SetVectorTable(NVIC_VectTab_FLASH, 0x0);  
 #endif

 /* enabling interrupt */
   NVIC_InitStructure.NVIC_IRQChannel = USB_LP_CAN1_RX0_IRQn;  
   NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
   NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
   NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
   NVIC_Init(&NVIC_InitStructure);
}

//配置系统时钟,使能各外设时钟
void RCC_Configuration(void)
{
 SystemInit(); 
 RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1 | RCC_APB2Periph_GPIOA
                           |RCC_APB2Periph_GPIOB | RCC_APB2Periph_GPIOC
                           |RCC_APB2Periph_GPIOD | RCC_APB2Periph_GPIOE
         |RCC_APB2Periph_ADC1  | RCC_APB2Periph_AFIO
                           |RCC_APB2Periph_SPI1, ENABLE );
  // RCC_APB2PeriphClockCmd(RCC_APB2Periph_ALL ,ENABLE );
     RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4
                           |RCC_APB1Periph_USART3|RCC_APB1Periph_TIM2                           
                           , ENABLE );
  RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
  RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE);
}

//配置所有外设
void Init_All_Periph(void)
{
 RCC_Configuration(); 
 GPIO_Configuration();
 NVIC_Configuration();
// USART1_Configuration();
}
int main(void)
{ 
 Init_All_Periph();

 /* CAN transmit at 100Kb/s and receive by polling in loopback mode*/
   TestRx = CAN_Polling();

   if (TestRx == FAILED)
   {
     /* Turn on led connected to PE.02 pin (LD2) */
     GPIO_SetBits(GPIOE, GPIO_Pin_2);
   }
   else
   {
     /* Turn on led connected to PD.02 pin (LD2) */
     GPIO_ResetBits(GPIOE, GPIO_Pin_2);
   }

   /* CAN transmit at 500Kb/s and receive by interrupt in loopback mode*/
   TestRx = CAN_Interrupt();

   if (TestRx == FAILED)
   {
      /* Turn on led connected to PE.04 pin (LD4) */
     GPIO_SetBits(GPIOE, GPIO_Pin_4);
   }
   else
   {
     /* Turn on led connected to PE.04 pin (LD4) */
     GPIO_ResetBits(GPIOE, GPIO_Pin_4);
  }
  while(1)
   {
   }
}

/*******************************************************************************
* Function Name  : CAN_Polling
* Description    : Configures the CAN and transmit and receive by polling
* Input          : None
* Output         : None
* Return         : PASSED if the reception is well done, FAILED in other case
*******************************************************************************/
TestStatus CAN_Polling(void)
{
  CAN_InitTypeDef        CAN_InitStructure;
  CAN_FilterInitTypeDef  CAN_FilterInitStructure;
  CanTxMsg TxMessage;
  CanRxMsg RxMessage;
  u32 i = 0;
  u8 TransmitMailbox;

  /* CAN register init */
  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_LoopBack;
  CAN_InitStructure.CAN_SJW=CAN_SJW_1tq;
  CAN_InitStructure.CAN_BS1=CAN_BS1_8tq;
  CAN_InitStructure.CAN_BS2=CAN_BS2_7tq;
  CAN_InitStructure.CAN_Prescaler=5;
  CAN_Init(CAN1,&CAN_InitStructure);

  /* 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);

  /* transmit */
  TxMessage.StdId=0x11;
  TxMessage.RTR=CAN_RTR_DATA;
  TxMessage.IDE=CAN_ID_STD;
  TxMessage.DLC=2;
  TxMessage.Data[0]=0xCA;
  TxMessage.Data[1]=0xFE;

  TransmitMailbox=CAN_Transmit(CAN1,&TxMessage);
  i = 0;
  while((CAN_TransmitStatus(CAN1,TransmitMailbox) != CANTXOK) && (i != 0xFF))
  {
    i++;
  }

  i = 0;
  while((CAN_MessagePending(CAN1,CAN_FIFO0) < 1) && (i != 0xFF))
  {
    i++;
  }

  /* receive */
  RxMessage.StdId=0x00;
  RxMessage.IDE=CAN_ID_STD;
  RxMessage.DLC=0;
  RxMessage.Data[0]=0x00;
  RxMessage.Data[1]=0x00;
  CAN_Receive(CAN1,CAN_FIFO0, &RxMessage);

  if (RxMessage.StdId!=0x11) return FAILED;

  if (RxMessage.IDE!=CAN_ID_STD) return FAILED;

  if (RxMessage.DLC!=2) return FAILED;

  if ((RxMessage.Data[0]<<8|RxMessage.Data[1])!=0xCAFE) return FAILED;
 
  return PASSED; /* Test Passed */
}

/*******************************************************************************
* Function Name  : CAN_Interrupt
* Description    : Configures the CAN and transmit and receive by interruption
* Input          : None
* Output         : None
* Return         : PASSED if the reception is well done, FAILED in other case
*******************************************************************************/
TestStatus CAN_Interrupt(void)
{
  CAN_InitTypeDef        CAN_InitStructure;
  CAN_FilterInitTypeDef  CAN_FilterInitStructure;
  CanTxMsg TxMessage;
  u32 i = 0;

  /* CAN register init */
  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_LoopBack;
  CAN_InitStructure.CAN_SJW=CAN_SJW_1tq;
  CAN_InitStructure.CAN_BS1=CAN_BS1_8tq;
  CAN_InitStructure.CAN_BS2=CAN_BS2_7tq;
  CAN_InitStructure.CAN_Prescaler=1;
  CAN_Init(CAN1,&CAN_InitStructure);

  /* CAN filter init */
  CAN_FilterInitStructure.CAN_FilterNumber=1;
  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 FIFO0 message pending interrupt enable */
  CAN_ITConfig(CAN1,CAN_IT_FMP0, ENABLE);

  /* transmit 1 message */
  TxMessage.StdId=0x00;
  TxMessage.ExtId=0x1234;
  TxMessage.IDE=CAN_ID_EXT;
  TxMessage.RTR=CAN_RTR_DATA;
  TxMessage.DLC=2;
  TxMessage.Data[0]=0xDE;
  TxMessage.Data[1]=0xCA;
  CAN_Transmit(CAN1,&TxMessage);

  /* initialize the value that will be returned */
  ret = 0xFF;
      
  /* receive message with interrupt handling */
  i=0;
  while((ret == 0xFF) && (i < 0xFFF))
  {
    i++;
  }
 
  if (i == 0xFFF)
  {
    ret=0; 
  }

  /* disable interrupt handling */
  CAN_ITConfig(CAN1,CAN_IT_FMP0, DISABLE);

  return (TestStatus)ret;
}

/*******************************************************************************
* Function Name  : USB_LP_CAN_RX0_IRQHandler
* Description    : This function handles USB Low Priority or CAN RX0 interrupts
*                  requests.
* Input          : None
* Output         : None
* Return         : None
*******************************************************************************/
void USB_LP_CAN1_RX0_IRQHandler(void)
{
  CanRxMsg RxMessage;

  RxMessage.StdId=0x00;
  RxMessage.ExtId=0x00;
  RxMessage.IDE=0;
  RxMessage.DLC=0;
  RxMessage.FMI=0;
  RxMessage.Data[0]=0x00;
  RxMessage.Data[1]=0x00;

  CAN_Receive(CAN1,CAN_FIFO0, &RxMessage);

  if((RxMessage.ExtId==0x1234) && (RxMessage.IDE==CAN_ID_EXT)
     && (RxMessage.DLC==2) && ((RxMessage.Data[1]|RxMessage.Data[0]<<8)==0xDECA))
  {
             //设置测试点，观察允许状态
               GPIO_ResetBits(GPIOE,GPIO_Pin_5);
        delay_nms(1000);   // LED1闪烁一次，发送一个字符
        GPIO_SetBits(GPIOE,GPIO_Pin_5);
        delay_nms(1000);
    ret = 1;
  }
  else
  {
    ret = 0;
  }
}