GD32F407的CAN1无法进入接收中断问题解决

和STM32F4类似，在使用GD32F4时，初始化不对会导致MCU的CAN1控制器在中断接收数据的时候无法产生中断。则需要如下初始化才行：

/*!
    \brief      initialize CAN and filter
    \param[in]  can_parameter
      \arg        can_parameter_struct
    \param[in]  can_filter
      \arg        can_filter_parameter_struct
    \param[out] none
    \retval     none
*/
void can_config(can_parameter_struct can_parameter, can_filter_parameter_struct can_filter)
{
    /* initialize CAN register */
    can_deinit(CAN0);
    can_deinit(CAN1);
    
    /* initialize CAN parameters */
    can_parameter.time_triggered = DISABLE;
    can_parameter.auto_bus_off_recovery = DISABLE;
    can_parameter.auto_wake_up = DISABLE;
    can_parameter.auto_retrans = DISABLE;
    can_parameter.rec_fifo_overwrite = DISABLE;
    can_parameter.trans_fifo_order = DISABLE;
    can_parameter.working_mode = CAN_NORMAL_MODE;
    can_parameter.resync_jump_width = CAN_BT_SJW_1TQ;
    can_parameter.time_segment_1 = CAN_BT_BS1_3TQ;
    can_parameter.time_segment_2 = CAN_BT_BS2_2TQ;
    
    /* 1MBps */
#if CAN_BAUDRATE == 1000
    can_parameter.prescaler = 5;
    /* 500KBps */
#elif CAN_BAUDRATE == 500 
    can_parameter.prescaler = 10;
    /* 250KBps */
#elif CAN_BAUDRATE == 250 
    can_parameter.prescaler = 20;
    /* 125KBps */
#elif CAN_BAUDRATE == 125 
    can_parameter.prescaler = 40;
    /* 100KBps */
#elif  CAN_BAUDRATE == 100 
    can_parameter.prescaler = 50;
    /* 50KBps */
#elif  CAN_BAUDRATE == 50 
    can_parameter.prescaler = 100;
    /* 20KBps */
#elif  CAN_BAUDRATE == 20 
    can_parameter.prescaler = 250;
#else
    #error "please select list can baudrate in private defines in main.c "
#endif  
    /* initialize CAN */
    can_init(CAN0, &can_parameter);
    can_init(CAN1, &can_parameter);
    
    /* initialize filter */ 
    can_filter.filter_number=0;
    can_filter.filter_mode = CAN_FILTERMODE_MASK;
    can_filter.filter_bits = CAN_FILTERBITS_32BIT;
    can_filter.filter_list_high = 0x3000;
    can_filter.filter_list_low = 0x0000;
    can_filter.filter_mask_high = 0x3000;
    can_filter.filter_mask_low = 0x0000;  
    can_filter.filter_fifo_number = CAN_FIFO0;
    can_filter.filter_enable = ENABLE;
    
    can_filter_init(&can_filter);
    
    /* CAN1 filter number */
    can_filter.filter_number = 15;
    can_filter_init(&can_filter);
}

这里有两句非常重要的代码：

    /* CAN1 filter number */
    can_filter.filter_number = 15;
    can_filter_init(&can_filter);

初始化有这两句，CAN1即可顺利产生接收