stm32f072 can时钟问题 500K波特率收不到消息

chendengfen

最近发现了一个can总线特别奇怪的问题，同样配置成250k，怎么配置都可以，配置成500k，怎么配置都不可以，现在怀疑自己的can时钟不对
      
这两个代码都可以收到数据

  //250K
    CAN_InitStructure.CAN_Prescaler = 16;
    CAN_InitStructure.CAN_BS1 = CAN_BS1_9tq;
    CAN_InitStructure.CAN_BS2 = CAN_BS2_2tq;
    CAN_InitStructure.CAN_SJW = CAN_SJW_1tq;
//250k
//        CAN_InitStructure.CAN_Prescaler = 12;
//        CAN_InitStructure.CAN_BS1 = CAN_BS1_13tq;
//        CAN_InitStructure.CAN_BS2 = CAN_BS2_2tq;
//        CAN_InitStructure.CAN_SJW = CAN_SJW_3tq;

但是如果配成500k的波特率一个都不行
    //500K
    CAN_InitStructure.CAN_Prescaler = 8;
    CAN_InitStructure.CAN_BS1 = CAN_BS1_9tq;
    CAN_InitStructure.CAN_BS2 = CAN_BS2_2tq;
    CAN_InitStructure.CAN_SJW = CAN_SJW_1tq;
//500K

//        CAN_InitStructure.CAN_Prescaler = 6;
//        CAN_InitStructure.CAN_BS1 = CAN_BS1_13tq;
//        CAN_InitStructure.CAN_BS2 = CAN_BS2_2tq;
//        CAN_InitStructure.CAN_SJW = CAN_SJW_3tq;

chendengfen

这个是完整的can驱动  

chendengfen

GPIO_InitTypeDef GPIO_InitStructure;
    CAN_InitTypeDef CAN_InitStructure;
    CAN_FilterInitTypeDef  CAN_FilterInitStructure;
    NVIC_InitTypeDef  NVIC_InitStructure;
   
    CAN_DeInit(CAN);
   
    RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA, ENABLE);
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN, ENABLE);
   
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource11,GPIO_AF_4);
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource12,GPIO_AF_4);
   
    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11|GPIO_Pin_12;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_Level_3;
    GPIO_Init(GPIOA, &GPIO_InitStructure);
   
   
   
    //250K
    CAN_InitStructure.CAN_Prescaler = 16;
    CAN_InitStructure.CAN_BS1 = CAN_BS1_9tq;
    CAN_InitStructure.CAN_BS2 = CAN_BS2_2tq;
    CAN_InitStructure.CAN_SJW = CAN_SJW_1tq;

CAN_InitStructure.CAN_Mode = CAN_Mode_Normal;//CAN_Mode_LoopBack;
    CAN_InitStructure.CAN_TTCM=DISABLE;                        
    CAN_InitStructure.CAN_ABOM=ENABLE;                        
    CAN_InitStructure.CAN_AWUM=DISABLE;                        
    CAN_InitStructure.CAN_NART=ENABLE;                        
    CAN_InitStructure.CAN_RFLM=DISABLE;                        
    CAN_InitStructure.CAN_TXFP=DISABLE;                        
    CAN_Init(CAN,&CAN_InitStructure);
   
    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_Filter_FIFO0;
    CAN_FilterInitStructure.CAN_FilterActivation=ENABLE;
    CAN_FilterInit(&CAN_FilterInitStructure);

    CAN_ITConfig(CAN,CAN_IT_FMP0,ENABLE);        
    NVIC_InitStructure.NVIC_IRQChannel = CEC_CAN_IRQn;
    NVIC_InitStructure.NVIC_IRQChannelPriority = 2;   
    NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStructure);
    //can_stb_init();