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Renesas瑞萨A4M2和STM32 CAN通信

article 2024/9/24 4:20:03

刚好拿到一块瑞萨开发板，捣鼓玩下CAN，顺便试下固件升级。

A4M2 工程创建

详细可以参考，我之前写的文章 Renesa 瑞萨 A4M2 移植文件系统FAT32
在这里插入图片描述
CAN0 配置信息，使能FIFO，接收标准帧 ID为0x50，数据帧。

代码

void can_Init(void)
{
    fsp_err_t err = R_CAN_Open(&g_can0_ctrl, &g_can0_cfg);
}

/* CAN 中断回调函数 */
void can_callback(can_callback_args_t * p_args)
{
    switch (p_args->event)
    {
        case CAN_EVENT_RX_COMPLETE: //接收完成中断
        {
            can_rx_complete_flag = true;    //can接收到数据

            /* 读取接收帧 */
            memcpy(&can_rx_frame, &(p_args->frame), sizeof(can_frame_t));

            break;
        }
        case CAN_EVENT_TX_COMPLETE: //传输完成中断
        {
            can_tx_complete_flag = true;    //can数据发送完成
            break;
        }
        case CAN_EVENT_ERR_BUS_OFF:          /* Bus error event. (bus off) */
        case CAN_EVENT_ERR_PASSIVE:          /* Bus error event. (error passive) */
        case CAN_EVENT_ERR_WARNING:          /* Bus error event. (error warning) */
        case CAN_EVENT_BUS_RECOVERY:         /* Bus error event. (bus recovery) */
        case CAN_EVENT_MAILBOX_MESSAGE_LOST: /* Overwrite/overrun error */
        {
            can_err_status_flag = true;     //设置标志位

            /* 获取错误状态 */
            can_err_status = (can_error_t) p_args->error;

            break;
        }
        default:
        {
            break;
        }
    }
}

发送数据

can_tx_frame.id               = 0x48;//发送ID
can_tx_frame.type             = CAN_FRAME_TYPE_DATA;
can_tx_frame.data_length_code = 8;  //一次最多发送8个字节
memcpy((uint8_t*)&can_tx_frame.data[0], (uint8_t*)"########", 8);
err = R_CAN_Write(&g_can0_ctrl, CAN_MAILBOX_NUMBER_0, &can_tx_frame);
/* Error trap */
if (FSP_SUCCESS != err)
{
		CAN_MSG_PRINTF("CAN Write API FAILED");
		//while(1);
}
/* 等待传输完成 */
while ((true != can_tx_complete_flag) && (--time_out));
can_tx_complete_flag = false;

//typedef struct st_can_frame
//{
//    uint32_t         id;                           ///< CAN ID.
//    can_id_mode_t    id_mode;                      ///< Standard or Extended ID (IDE).
//    can_frame_type_t type;                         ///< Frame type (RTR).
//    uint8_t          data_length_code;             ///< CAN Data Length Code (DLC).
//    uint32_t         options;                      ///< Implementation-specific options.
//    uint8_t          data[CAN_DATA_BUFFER_LENGTH]; ///< CAN data.
//} can_frame_t;

//接收数据
while (false == can_rx_complete_flag);
can_rx_complete_flag = false;
printf("%s",can_rx_frame.data)

STM32 CAN工程

CAN外设初始化

#define TX_CAN_UPDATE 0x50
#define RX_CAN_UPDATE 0x48

u8 CAN1_Mode_Init(u8 tsjw,u8 tbs2,u8 tbs1,u16 brp,u8 mode)
{

  	GPIO_InitTypeDef GPIO_InitStructure; 
	  CAN_InitTypeDef        CAN_InitStructure;
  	CAN_FilterInitTypeDef  CAN_FilterInitStructure;
   	NVIC_InitTypeDef  NVIC_InitStructure;
	  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);//使能PORTA时钟	                   											 

  	RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE);//使能CAN1时钟	
	
    //初始化GPIO
	  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11| GPIO_Pin_12;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;//复用功能
    GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;//推挽输出
    GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;//100MHz
    GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;//上拉
    GPIO_Init(GPIOA, &GPIO_InitStructure);//初始化PA11,PA12
	
	  //引脚复用映射配置
	  GPIO_PinAFConfig(GPIOA,GPIO_PinSource11,GPIO_AF_CAN1); //GPIOA11复用为CAN1
	  GPIO_PinAFConfig(GPIOA,GPIO_PinSource12,GPIO_AF_CAN1); //GPIOA12复用为CAN1
	  
  	//CAN单元设置
   	CAN_InitStructure.CAN_TTCM=DISABLE;	//非时间触发通信模式   
  	CAN_InitStructure.CAN_ABOM=DISABLE;	//软件自动离线管理	  
  	CAN_InitStructure.CAN_AWUM=DISABLE;//睡眠模式通过软件唤醒(清除CAN->MCR的SLEEP位)
  	CAN_InitStructure.CAN_NART=ENABLE;	//禁止报文自动传送 
  	CAN_InitStructure.CAN_RFLM=DISABLE;	//报文不锁定,新的覆盖旧的  
  	CAN_InitStructure.CAN_TXFP=DISABLE;	//优先级由报文标识符决定 
  	CAN_InitStructure.CAN_Mode= mode;	 //模式设置 
  	CAN_InitStructure.CAN_SJW=tsjw;	//重新同步跳跃宽度(Tsjw)为tsjw+1个时间单位 CAN_SJW_1tq~CAN_SJW_4tq
  	CAN_InitStructure.CAN_BS1=tbs1; //Tbs1范围CAN_BS1_1tq ~CAN_BS1_16tq
  	CAN_InitStructure.CAN_BS2=tbs2;//Tbs2范围CAN_BS2_1tq ~	CAN_BS2_8tq
  	CAN_InitStructure.CAN_Prescaler=brp;  //分频系数(Fdiv)为brp+1	
  	CAN_Init(CAN1, &CAN_InitStructure);   // 初始化CAN1 
    
		//配置过滤器
 	  CAN_FilterInitStructure.CAN_FilterNumber=0;	  //过滤器0

	 u32 ID1 = RX_CAN_UPDATE;
	 u32 ID2 = TX_CAN_UPDATE;

    CAN_FilterInitStructure.CAN_FilterMode = CAN_FilterMode_IdList; 
    CAN_FilterInitStructure.CAN_FilterScale = CAN_FilterScale_32bit;
    ID1 %= (1 << 11);
    ID2%= (1 << 11);
    //标准帧的帧ID长度是11位，帧ID的范围是000-7FF。
    //扩展帧的帧ID长度是29位，帧ID的范围是0000 0000-1FFF FFFF
    CAN_FilterInitStructure.CAN_FilterIdHigh = ID1  << 5; 
    CAN_FilterInitStructure.CAN_FilterIdLow = CAN_ID_STD | CAN_RTR_DATA;
    CAN_FilterInitStructure.CAN_FilterMaskIdHigh = ID2 << 5;
    CAN_FilterInitStructure.CAN_FilterMaskIdLow = CAN_ID_STD | CAN_RTR_DATA;
    CAN_FilterInitStructure.CAN_FilterFIFOAssignment = CAN_FIFO0;
    CAN_FilterInitStructure.CAN_FilterActivation = ENABLE; 
    CAN_FilterInit(&CAN_FilterInitStructure);
		

	 CAN_ITConfig(CAN1,CAN_IT_FMP0,ENABLE);//FIFO0消息挂号中断允许.		    
  
  	NVIC_InitStructure.NVIC_IRQChannel = CAN1_RX0_IRQn;
  	NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;     // 主优先级为1
  	NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;            // 次优先级为0
  	NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
  	NVIC_Init(&NVIC_InitStructure);
	return 0;
}   

void CAN1_RX0_IRQHandler(void)
{
	u8 i =0;
	CanRxMsg msg;
	CAN_Receive(CAN1, CAN_FIFO0, &msg);

	if(msg.IDE == CAN_ID_STD && msg.StdId == RX_CAN_UPDATE)
	{
		for(i=0;i<msg.DLC;i++){
			Rx_Buffer[i] = msg.Data[i];
		}
	}

以上配置只会收到数据帧的ID为0x50和0x48，其他都会被过滤掉。
关于这部分，可以看我之前写 STM32 CAN通信理解(是半双工还是全双工？)

开发版间CAN通信发送和接收都正常。

在这里插入图片描述
OTA也正常。

使用CAN通信，主要是想为固件升级教程，使用CAN做通信升级做些准备。后面有空持续更新这个系列教程 MCU固件升级系列1（STM32）