STM32 CAN通信接收带不同标识符的数据帧问题

qianzhang

            如题，我有STM32 CAN通信能够接收某一标识符的数据，使用IdMask模式。

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

  //NVIC_Configuration();
  GPIO_Configuration();
  /* CAN register init */
  CAN_DeInit(CAN1);
  CAN_StructInit(&CAN_InitStructure);

  /* 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_InitStructure.CAN_SJW = CAN_SJW_1tq;
  CAN_InitStructure.CAN_BS1 = CAN_BS1_4tq;
  CAN_InitStructure.CAN_BS2 = CAN_BS2_3tq;
  CAN_InitStructure.CAN_Prescaler = 45;

  if (CAN_Init(CAN1,&CAN_InitStructure) == CANINITFAILED)   
  {
  } 

  CAN_FilterInitStructure.CAN_FilterNumber=0;
  CAN_FilterInitStructure.CAN_FilterMode=CAN_FilterMode_IdMask;
  CAN_FilterInitStructure.CAN_FilterScale=CAN_FilterScale_32bit;
  CAN_FilterInitStructure.CAN_FilterIdHigh=(((u32)0x0111<<21)&0xffff0000)>>16;
  CAN_FilterInitStructure.CAN_FilterIdLow=(((u32)0x0111<<21)|CAN_ID_STD|CAN_RTR_DATA)&0xffff;
  CAN_FilterInitStructure.CAN_FilterMaskIdHigh=0xFFFF;
  CAN_FilterInitStructure.CAN_FilterMaskIdLow=0xFFFF;
  CAN_FilterInitStructure.CAN_FilterFIFOAssignment=0;
  CAN_FilterInitStructure.CAN_FilterActivation=ENABLE;
  CAN_ITConfig(CAN1,CAN_IT_FMP0, ENABLE);
  CAN_FilterInit(&CAN_FilterInitStructure);
}

 

这样设置后，可以接受标识符为0x0111的数据帧。

       但现在想接收不同标识符的数据。根据STM32中文手册：

                一旦收到的报文被存入FIFO，就可被应用程序访问。通常情况下，报文中的数据被拷贝到
               SRAM 中；为了把数据拷贝到合适的位置，应用程序需要根据报文的标识符来辨别不同的数
               据。bxCAN提供了过滤器匹配序号，以简化这一辨别过程。
              根据过滤器优先级规则，过滤器匹配序号和报文一起，被存入邮箱中。因此每个收到的报文，
              都有与它相关联的过滤器匹配序号。
             过滤器匹配序号可以通过下面两种方式来使用：
                       ●  把过滤器匹配序号跟一系列所期望的值进行比较
                       ●  把过滤器匹配序号当作一个索引来访问目标地址

              过滤器匹配序号存放在CAN_RDTxR 寄存器的FMI 域中。

        那么我是不是可以在程序中多设置几个CAN_Configuration(void)，里面的设置不同的CAN_FilterNumber和CAN_FilterIdHigh，CAN_FilterIdLow。比如

void CAN_Configuration1(void)
{
  CAN_InitTypeDef        CAN_InitStructure;
  CAN_FilterInitTypeDef  CAN_FilterInitStructure;

  //NVIC_Configuration();
  GPIO_Configuration();
  /* CAN register init */
  CAN_DeInit(CAN1);
  CAN_StructInit(&CAN_InitStructure);

  /* 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_InitStructure.CAN_SJW = CAN_SJW_1tq;
  CAN_InitStructure.CAN_BS1 = CAN_BS1_4tq;
  CAN_InitStructure.CAN_BS2 = CAN_BS2_3tq;
  CAN_InitStructure.CAN_Prescaler = 45;

  if (CAN_Init(CAN1,&CAN_InitStructure) == CANINITFAILED)   
  {
  } 

  CAN_FilterInitStructure.CAN_FilterNumber=1;
  CAN_FilterInitStructure.CAN_FilterMode=CAN_FilterMode_IdMask;
  CAN_FilterInitStructure.CAN_FilterScale=CAN_FilterScale_32bit;
  CAN_FilterInitStructure.CAN_FilterIdHigh=(((u32)0x0112<<21)&0xffff0000)>>16;
  CAN_FilterInitStructure.CAN_FilterIdLow=(((u32)0x0112<<21)|CAN_ID_STD|CAN_RTR_DATA)&0xffff;
  CAN_FilterInitStructure.CAN_FilterMaskIdHigh=0xFFFF;
  CAN_FilterInitStructure.CAN_FilterMaskIdLow=0xFFFF;
  CAN_FilterInitStructure.CAN_FilterFIFOAssignment=0;
  CAN_FilterInitStructure.CAN_FilterActivation=ENABLE;
  CAN_ITConfig(CAN1,CAN_IT_FMP0, ENABLE);
  CAN_FilterInit(&CAN_FilterInitStructure);
}

 

最后在接收中断函数里面读取RxMessage.FMI的值，判断是哪帧数据？ 

 

正点原子

回复【楼主位】qianzhang:
---------------------------------
设置多个CAN_Configuration1函数,是不对的.
因为在你的CAN_Configuration1函数里面,会把之前的CAN初始化全给清掉了,也就前面代码都白忙活了...
你只需要设置多个过滤器即可.
也就是:
  CAN_FilterInitStructure.CAN_FilterNumber=1;
  CAN_FilterInitStructure.CAN_FilterMode=CAN_FilterMode_IdMask;
  CAN_FilterInitStructure.CAN_FilterScale=CAN_FilterScale_32bit;
  CAN_FilterInitStructure.CAN_FilterIdHigh=(((u32)0x0112<<21)&0xffff0000)>>16;
  CAN_FilterInitStructure.CAN_FilterIdLow=(((u32)0x0112<<21)|CAN_ID_STD|CAN_RTR_DATA)&0xffff;
  CAN_FilterInitStructure.CAN_FilterMaskIdHigh=0xFFFF;
  CAN_FilterInitStructure.CAN_FilterMaskIdLow=0xFFFF;
  CAN_FilterInitStructure.CAN_FilterFIFOAssignment=0;
  CAN_FilterInitStructure.CAN_FilterActivation=ENABLE;
  CAN_ITConfig(CAN1,CAN_IT_FMP0, ENABLE);
  CAN_FilterInit(&CAN_FilterInitStructure);
这部分代码,可以设置多次

qianzhang

回复【2楼】正点原子:

回复【楼主位】qianzhang:
---------------------------------
设置多个CAN_Configuration1函数,是不对的.
因为在你的CAN_Configuration1函数里面,会把之前的CAN初始化全给清掉了,也就前面代码都白忙活了...
你只需要设置多个过滤器即可.
也就是:
  CAN_FilterInitStructure.CAN_FilterNumber=1;
  CAN_FilterInitStructure.CAN_FilterMode=CAN_FilterMode_IdMask;
  CAN_FilterInitStructure.CAN_FilterScale=CAN_FilterScale_32bit;
  CAN_FilterInitStructure.CAN_FilterIdHigh=(((u32)
......
---------------------------------
嗯，开始试了不行，不知道为什么，原来是清掉了
现在在一个函数蝻设置多次，可以运行，谢谢原子哥