使用can1原来使用baud rate:1Mbit,通讯正常

改为:250k ,就无法正常收发数据,请各位帮忙看看问题点所在

#if 0
      Can1_Handle.Instance = CAN1;
      Can1_Handle.Init.Prescaler = 6;
      Can1_Handle.Init.Mode = CAN_MODE_NORMAL;
      Can1_Handle.Init.SyncJumpWidth = CAN_SJW_1TQ;
      Can1_Handle.Init.TimeSeg1 = CAN_BS1_5TQ;
      Can1_Handle.Init.TimeSeg2 = CAN_BS2_3TQ;
      Can1_Handle.Init.TimeTriggeredMode = DISABLE;
      Can1_Handle.Init.AutoBusOff = ENABLE;
      Can1_Handle.Init.AutoWakeUp = ENABLE;
      Can1_Handle.Init.AutoRetransmission = DISABLE;
      Can1_Handle.Init.ReceiveFifoLocked = DISABLE;
      Can1_Handle.Init.TransmitFifoPriority = DISABLE;
      if (HAL_CAN_Init(&Can1_Handle) != HAL_OK)
      {
        Error_Handler();
      }
  #endif  
  //250kbps --> CAN_BS1_7TQ ,CAN_BS2_1TQ  ,Prescaler =24
      #if 1
      Can1_Handle.Instance = CAN1;
      Can1_Handle.Init.Prescaler = 24;
      Can1_Handle.Init.Mode = CAN_MODE_NORMAL;
      Can1_Handle.Init.SyncJumpWidth = CAN_SJW_1TQ;
      Can1_Handle.Init.TimeSeg1 = CAN_BS1_7TQ;
      Can1_Handle.Init.TimeSeg2 = CAN_BS2_1TQ;
      Can1_Handle.Init.TimeTriggeredMode = DISABLE;
      Can1_Handle.Init.AutoBusOff = ENABLE;
      Can1_Handle.Init.AutoWakeUp = ENABLE;
      Can1_Handle.Init.AutoRetransmission = DISABLE;
      Can1_Handle.Init.ReceiveFifoLocked = DISABLE;
      Can1_Handle.Init.TransmitFifoPriority = DISABLE;
      if (HAL_CAN_Init(&Can1_Handle) != HAL_OK)
      {
        Error_Handler();
      }
   #endif

找一个工具，算一下这三个参数的配置，或者找一下主频相同的例程的配置，只修改分频参数，可能时钟有偏差。
      Can1_Handle.Init.SyncJumpWidth = CAN_SJW_1TQ;
      Can1_Handle.Init.TimeSeg1 = CAN_BS1_5TQ;
      Can1_Handle.Init.TimeSeg2 = CAN_BS2_3TQ;

通常都会用LOOP BACK 模式先测试一下能否发送出

通常都会用LOOP BACK 模式先测试一下能否发送出

找到计算baudrate software 如下:

STM32 CAN波特率设置_河西剑客的博客-CSDN博客_stm32can波特率设置
use hsi mode

     Can1_Handle.Instance = CAN1;

      Can1_Handle.Init.Prescaler =31;

      Can1_Handle.Init.Mode = CAN_MODE_NORMAL;

      Can1_Handle.Init.SyncJumpWidth = CAN_SJW_1TQ;

      Can1_Handle.Init.TimeSeg1 = CAN_BS1_5TQ;

      Can1_Handle.Init.TimeSeg2 = CAN_BS2_1TQ;

      Can1_Handle.Init.TimeTriggeredMode = DISABLE;

      Can1_Handle.Init.AutoBusOff = ENABLE;

      Can1_Handle.Init.AutoWakeUp = ENABLE;

      Can1_Handle.Init.AutoRetransmission = DISABLE;

      Can1_Handle.Init.ReceiveFifoLocked = DISABLE;

      Can1_Handle.Init.TransmitFifoPriority = DISABLE;

      if (HAL_CAN_Init(&Can1_Handle) != HAL_OK)

      {

        Error_Handler();

      }

我有两片evbboard,这样可以通讯,但跑没几次就停掉了

如果设定成1Mbit ,就没问题

jxchen 发表于 2022-7-7 12:25
找到计算baudrate software 如下:
STM32 CAN波特率设置_河西剑客的博客-CSDN博客_stm32can波特率设置
use  ...

应该还是频率不对，计算的时候是用的你实际的频率算的吗？

leekuip 发表于 2022-7-7 16:32
应该还是频率不对，计算的时候是用的你实际的频率算的吗？

初步排除方法,打开中断错误中断

并将中断内检查旗号与清除

          if(CAN_GetITStatus(CANx, CAN_IT_ERR ) == SET )

    {

        CAN_ClearITPendingBit( CANx, CAN_IT_ERR );

    }

已经跑了半小时,不会停掉