STM32F4 CAN发送失败

只看该作者 · 2016-4-2 13:43

在使用STM32F405调试CAN的时，使用官方的例程的环回模式时，数据收发都可以，但是将环回模式更改为正常模式，且接上CAN卡想抓数据时，发现发送数据失败（超时）， CAN初始化代码如下：

void CanComInit(void)
{
  CAN_InitTypeDef       CAN_InitStructure;
  CAN_FilterInitTypeDef  CAN_FilterInitStructure;

  //// CAN register init
  CAN_DeInit(CAN_ONE_PERIPH_PORT);

  //// 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_Mode_LoopBack;
  CAN_InitStructure.CAN_SJW = CAN_SJW_1tq;

  //// Baudrate (CAN clocked at 42 MHz)
//// Baudrate = 42 MHz/((1+BS1+BS2)*CAN_Prescaler)
  CAN_InitStructure.CAN_BS1 = CAN_BS1_13tq;
  CAN_InitStructure.CAN_BS2 = CAN_BS2_8tq;
  CAN_InitStructure.CAN_Prescaler = 2;
  CAN_Init(CAN_ONE_PERIPH_PORT, &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 = 0x0020; //// StdId = 0x01
  CAN_FilterInitStructure.CAN_FilterIdLow = 0x0000;
  CAN_FilterInitStructure.CAN_FilterMaskIdHigh = 0x003F;
  CAN_FilterInitStructure.CAN_FilterMaskIdLow = 0xFFFF;
  CAN_FilterInitStructure.CAN_FilterFIFOAssignment = 0;
  CAN_FilterInitStructure.CAN_FilterActivation = ENABLE;
  CAN_FilterInit(&CAN_FilterInitStructure);

test = 1;
while(1)
{
//// transmit
TxMessage.StdId = test;
TxMessage.RTR = CAN_RTR_DATA;
TxMessage.IDE = CAN_ID_STD;
TxMessage.DLC = 2;
TxMessage.Data[0] = 0xCA;
TxMessage.Data[1] = 0xFf;

TransmitMailbox = CAN_Transmit(CAN_ONE_PERIPH_PORT, &TxMessage);
num = 0;
while((CAN_TransmitStatus(CAN_ONE_PERIPH_PORT, TransmitMailbox)  !=  CANTXOK) && (num  !=  0xFFFFF))
{
num++;
}

//// num = 0;
//// while((CAN_MessagePending(CAN_ONE_PERIPH_PORT, CAN_FIFO0) < 1) && (num  !=  0xFFFF))
//// {
//// num++;
//// }

//// //// receive
//// RxMessage.StdId = 0x00;
//// RxMessage.IDE = CAN_ID_STD;
//// RxMessage.DLC = 0;
//// RxMessage.Data[0] = 0x00;
//// RxMessage.Data[1] = 0x00;
//// CAN_Receive(CAN_ONE_PERIPH_PORT, CAN_FIFO0, &RxMessage);

//// if (RxMessage.StdId != 0x11)
//// {
//// RxMessage.StdId = 0xFF;
//// }
}
}

发送后，num  ==  0xFFFFF 退出循环...
代码只是将环回模式更改为正常模式，其余没有更改，不知道为什么？？？

求指点...

只看该作者 · 2016-4-2 18:33

波特率，终端电阻，无非就这些

只看该作者 · 2016-4-3 23:08

楼上的说的对，波特率设置错误，应该是：CAN_InitStructure.CAN_BS1 = CAN_BS1_12tq;

只看该作者 · 2016-4-4 16:50

icefox225 发表于 2016-4-2 18:33
波特率，终端电阻，无非就这些