STM32F205 CAN通信问题 【悬赏问答】

uniqueeefocus34

用的stm32f2xx_stdperiph_lib里的示例程序做CAN通信测试，环回模式测试OK。正常模式下，用CAN调试软件向板子发数据，始终进不了接收中断
.c文件
int main(void)
{
 
  /* NVIC configuration */
  NVIC_Config();

  /* CAN configuration */
  CAN_Config();
 
  /* Infinite loop */
  while(1)
  {
        Delay();
  }
}
 
void CAN_Config(void)
{
  GPIO_InitTypeDef  GPIO_InitStructure;
 
  /* CAN GPIOs configuration **************************************************/

  /* Enable GPIO clock */
  RCC_AHB1PeriphClockCmd(CAN_GPIO_CLK, ENABLE);

  GPIO_PinAFConfig(CAN_GPIO_PORT, CAN_RX_SOURCE, CAN_AF_PORT);
  GPIO_PinAFConfig(CAN_GPIO_PORT, CAN_TX_SOURCE, CAN_AF_PORT);

  /* Configure CAN RX and TX pins */
  GPIO_InitStructure.GPIO_Pin = CAN_RX_PIN | CAN_TX_PIN;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
  GPIO_InitStructure.GPIO_PuPd  = GPIO_PuPd_UP;
  GPIO_Init(CAN_GPIO_PORT, &GPIO_InitStructure);

  /* CAN configuration ********************************************************/ 
  /* Enable CAN clock */
  RCC_APB1PeriphClockCmd(CAN_CLK, ENABLE);
 
  /* CAN register init */
  CAN_DeInit(CANx);

  /* 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 Baudrate = 1MBps (CAN clocked at 30 MHz) */
  /*CAN_InitStructure.CAN_BS1 = CAN_BS1_6tq;
  CAN_InitStructure.CAN_BS2 = CAN_BS2_8tq;
  CAN_InitStructure.CAN_Prescaler = 2;
  CAN_Init(CANx, &CAN_InitStructure);*/
 

  /* CAN filter init */
#ifdef  USE_CAN1
  CAN_FilterInitStructure.CAN_FilterNumber = 0;
#else /* USE_CAN2 */
  CAN_FilterInitStructure.CAN_FilterNumber = 14;
#endif  /* USE_CAN1 */
  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);
   
  /* Enable FIFO 0 message pending Interrupt */
  CAN_ITConfig(CANx, CAN_IT_FMP0, ENABLE);
}
 
void NVIC_Config(void)
{
  NVIC_InitTypeDef  NVIC_InitStructure;

#ifdef  USE_CAN1
  NVIC_InitStructure.NVIC_IRQChannel = CAN1_RX0_IRQn;
#else  /* USE_CAN2 */
  NVIC_InitStructure.NVIC_IRQChannel = CAN2_RX0_IRQn;
#endif /* USE_CAN1 */

  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x0;
  NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x0;
  NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  NVIC_Init(&NVIC_InitStructure);
}
 
.h头文件
#define USE_CAN1
//#define USE_CAN2

#ifdef  USE_CAN1
  #define CANx                       CAN1
  #define CAN_CLK                    RCC_APB1Periph_CAN1
  #define CAN_RX_PIN                 GPIO_Pin_11
  #define CAN_TX_PIN                 GPIO_Pin_12
  #define CAN_GPIO_PORT              GPIOA
  #define CAN_GPIO_CLK               RCC_AHB1Periph_GPIOA
  #define CAN_AF_PORT                GPIO_AF_CAN1
  #define CAN_RX_SOURCE              GPIO_PinSource11
  #define CAN_TX_SOURCE              GPIO_PinSource12      
#else /*USE_CAN2*/
  #define CANx                       CAN2
  #define CAN_CLK                    (RCC_APB1Periph_CAN1 | RCC_APB1Periph_CAN2)
  #define CAN_RX_PIN                 GPIO_Pin_12
  #define CAN_TX_PIN                 GPIO_Pin_13
  #define CAN_GPIO_PORT              GPIOB
  #define CAN_GPIO_CLK               RCC_AHB1Periph_GPIOB
  #define CAN_AF_PORT                GPIO_AF_CAN2
  #define CAN_RX_SOURCE              GPIO_PinSource12
  #define CAN_TX_SOURCE              GPIO_PinSource13   
#endif  /* USE_CAN1 */
 
 
stm32f2xx_it.c 文件中涉及的CAN接收中断程序
#ifdef USE_CAN1
void CAN1_RX0_IRQHandler(void)
{
  CAN_Receive(CAN1, CAN_FIFO0, &RxMessage);
   CAN_FIFORelease(CAN2, CAN_FIFO0);
}
#endif  /* USE_CAN1 */

#ifdef USE_CAN2
/**
  * @brief  This function handles CAN2 RX0 request.
  * @param  None
  * @retval None
  */
void CAN2_RX0_IRQHandler(void)
{
  CAN_Receive(CAN2, CAN_FIFO0, &RxMessage);
    CAN_FIFORelease(CAN2, CAN_FIFO0);
}
#endif  /* USE_CAN2 */
 
以上，PC端通过USB-CAN-A2设备与板子连接，CAN调试工具不断发数据。用示波器测收发器的CANH及CANL脚，有脉冲波形，说明CAN口能正常接收到PC端数据。但测收发器的RX脚(RX脚连MCU引出的PA11脚，复用为CAN_RX功能)始终为高电平，没有收到有效信号。
 

安

你没有开启FAIO和IO口的时钟。

uniqueeefocus34

/* Enable GPIO clock */
  RCC_AHB1PeriphClockCmd(CAN_GPIO_CLK, ENABLE);

xiaodc88

要开启管脚的复用功能吧

xieyuanfu

CAN 的接收中断 你还没开啊  怎么样进中断啊