使用can驱动会卡死在接收中断，一直产生接收中断，最终定位在overrun中断

发布于 2021-04-21 00:13:10 浏览：3434 订阅该版

```c
/**
 * @brief This function handles CAN1 RX0 interrupts.
 */
void CAN1_RX0_IRQHandler(void)
{
    rt_interrupt_enter();
    _can_rx_isr(&drv_can1.device, CAN_RX_FIFO0);   //一直产生这个中断
    rt_interrupt_leave();
}
static void _can_rx_isr(struct rt_can_device *can, rt_uint32_t fifo)
{
    CAN_HandleTypeDef *hcan;
    RT_ASSERT(can);
    hcan = &((struct stm32_can *) can->parent.user_data)->CanHandle;

switch (fifo)
    {
    case CAN_RX_FIFO0:
        /* save to user list */
        if (HAL_CAN_GetRxFifoFillLevel(hcan, CAN_RX_FIFO0) && __HAL_CAN_GET_IT_SOURCE(hcan, CAN_IT_RX_FIFO0_MSG_PENDING))
        {
            rt_hw_can_isr(can, RT_CAN_EVENT_RX_IND | fifo << 8);
        }
        /* Check FULL flag for FIFO0 */
        if (__HAL_CAN_GET_FLAG(hcan, CAN_FLAG_FF0) && __HAL_CAN_GET_IT_SOURCE(hcan, CAN_IT_RX_FIFO0_FULL))
        {
            /* Clear FIFO0 FULL Flag */
            __HAL_CAN_CLEAR_FLAG(hcan, CAN_FLAG_FF0);
        }

/* Check Overrun flag for FIFO0 */
        if (__HAL_CAN_GET_FLAG(hcan, CAN_FLAG_FOV0) && __HAL_CAN_GET_IT_SOURCE(hcan, CAN_IT_RX_FIFO0_OVERRUN))
        {
            /* Clear FIFO0 Overrun Flag */
            __HAL_CAN_CLEAR_FLAG(hcan, CAN_FLAG_FOV0);
            rt_hw_can_isr(can, RT_CAN_EVENT_RXOF_IND | fifo << 8);
        }
        break;
    case CAN_RX_FIFO1:
        /* save to user list */
        if (HAL_CAN_GetRxFifoFillLevel(hcan, CAN_RX_FIFO1) && __HAL_CAN_GET_IT_SOURCE(hcan, CAN_IT_RX_FIFO1_MSG_PENDING))
        {
            rt_hw_can_isr(can, RT_CAN_EVENT_RX_IND | fifo << 8);
        }
        /* Check FULL flag for FIFO1 */
        if (__HAL_CAN_GET_FLAG(hcan, CAN_FLAG_FF1) && __HAL_CAN_GET_IT_SOURCE(hcan, CAN_IT_RX_FIFO1_FULL))
        {
            /* Clear FIFO1 FULL Flag */
            __HAL_CAN_CLEAR_FLAG(hcan, CAN_FLAG_FF1);
        }

/* Check Overrun flag for FIFO1 */
        if (__HAL_CAN_GET_FLAG(hcan, CAN_FLAG_FOV1) && __HAL_CAN_GET_IT_SOURCE(hcan, CAN_IT_RX_FIFO1_OVERRUN))
        {
            /* Clear FIFO1 Overrun Flag */
            __HAL_CAN_CLEAR_FLAG(hcan, CAN_FLAG_FOV1);
            rt_hw_can_isr(can, RT_CAN_EVENT_RXOF_IND | fifo << 8);  //一直进入这个中断
        }
        break;
    }
}
```

4 个回答

flashman2002 2021-04-21

这家伙很懒，什么也没写！

SimonLeung 2021-08-27

这家伙很懒，什么也没写！

SimonLeung 2021-08-28

这家伙很懒，什么也没写！

1 插拔线、振动时线松动，会导致发送出错，hcan->State = HAL_CAN_STATE_ERROR；
```
static int _can_sendmsg(struct rt_can_device *can, const void *buf, rt_uint32_t box_num)
{
    CAN_HandleTypeDef *hcan;
    hcan = &((struct stm32_can *) can->parent.user_data)->CanHandle;
    struct rt_can_msg *pmsg = (struct rt_can_msg *) buf;
    CAN_TxHeaderTypeDef txheader = {0};
    HAL_CAN_StateTypeDef state = hcan->State;

/* Check the parameters */
    RT_ASSERT(IS_CAN_DLC(pmsg->len));

if ((state == HAL_CAN_STATE_READY) ||
            (state == HAL_CAN_STATE_LISTENING))
    {
        /*check select mailbox  is empty */
        switch (1 << box_num)
        {
        case CAN_TX_MAILBOX0:
            if (HAL_IS_BIT_SET(hcan->Instance->TSR, CAN_TSR_TME0) != SET)
            {
                /* Change CAN state */
                hcan->State = HAL_CAN_STATE_ERROR;
                /* Return function status */
                return -RT_ERROR;
            }
            break;
```

2 此时因插拔线导致接收了些乱的帧或者过载，进接收中断，但进HAL_CAN_GetRxMessage因hcan->State为 HAL_CAN_STATE_ERROR退出了，邮箱有数据但就是读不出来，于是不断疯狂进中断，系统就像死机一样。

上面贴的那段代码是不是不应该操作hcan->State，插拔线这种操作，CAN又不是出什么错，一旦变HAL_CAN_STATE_ERROR，所有正常库函数操作不了