配置

打開env工具，輸入menuconfig,打開圖形配置界面，選擇Hardware Drivers Conifg---->On-chip Peripheral Drivers-->Enable CAN-->啟動Using CAN1
添加 can測試文件。用vscode打開rtthread目錄添加can_sample.c函數(shù)如下：

/*
 * Copyright (c) 2006-2021, RT-Thread Development Team
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Change Logs:
 * Date           Author       Notes
 * 2023-02-01     Administrator       the first version
 */
/*
 * 程序清單：這是一個 CAN 設備使用例程
 * 例程導出了 can_sample 命令到控制終端
 * 命令調(diào)用格式：can_sample can1
 * 命令解釋：命令第二個參數(shù)是要使用的 CAN 設備名稱，為空則使用默認的 CAN 設備
 * 程序功能：通過 CAN 設備發(fā)送一幀，并創(chuàng)建一個線程接收數(shù)據(jù)然后打印輸出。
*/

#include 
#include "rtdevice.h"

#define CAN_DEV_NAME       "can1"      /* CAN 設備名稱 */
static struct rt_semaphore rx_sem;     /* 用于接收消息的信號量 */
static rt_device_t can_dev;            /* CAN 設備句柄 */
/* 接收數(shù)據(jù)回調(diào)函數(shù) */
static rt_err_t can_rx_call(rt_device_t dev, rt_size_t size)
{
    /* CAN 接收到數(shù)據(jù)后產(chǎn)生中斷，調(diào)用此回調(diào)函數(shù)，然后發(fā)送接收信號量 */
    rt_sem_release(&rx_sem);
    
    return RT_EOK;
}

int can_send(rt_uint32_t humi,rt_uint32_t temp)
{
    struct rt_can_msg msg = {0};
    rt_err_t res;
    rt_size_t  size;
    msg.id = 0x78;              /* ID 為 0x78 */
       msg.ide = RT_CAN_STDID;     /* 標準格式 */
       msg.rtr = RT_CAN_DTR;       /* 數(shù)據(jù)幀 */
       msg.len = 8;                /* 數(shù)據(jù)長度為 8 */
       /* 待發(fā)送的 8 字節(jié)數(shù)據(jù) */
       msg.data[0] = (uint8_t)(temp/100);
       msg.data[1] = (uint8_t)(temp%100);
       msg.data[2] = (uint8_t)(humi/100);
       msg.data[3] = (uint8_t)(humi%100);
       msg.data[4] = 0x44;
       msg.data[5] = 0x55;
       msg.data[6] = 0x66;
       msg.data[7] = 0x77;
       /* 發(fā)送一幀 CAN 數(shù)據(jù) */
       size = rt_device_write(can_dev, 0, &msg, sizeof(msg));
       if (size == 0)
       {
           rt_kprintf("can dev write data failed!
");
       }

       return res;
}

static void can_rx_thread(void *parameter)
{
    int i;
    rt_err_t res;
    struct rt_can_msg rxmsg = {0};

    /* 設置接收回調(diào)函數(shù) */
    rt_device_set_rx_indicate(can_dev, can_rx_call);

#ifdef RT_CAN_USING_HDR
    struct rt_can_filter_item items[5] =
    {
        RT_CAN_FILTER_ITEM_INIT(0x100, 0, 0, 0, 0x700, RT_NULL, RT_NULL), /* std,match ID:0x100~0x1ff，hdr 為 - 1，設置默認過濾表 */
        RT_CAN_FILTER_ITEM_INIT(0x300, 0, 0, 0, 0x700, RT_NULL, RT_NULL), /* std,match ID:0x300~0x3ff，hdr 為 - 1 */
        RT_CAN_FILTER_ITEM_INIT(0x211, 0, 0, 0, 0x7ff, RT_NULL, RT_NULL), /* std,match ID:0x211，hdr 為 - 1 */
        RT_CAN_FILTER_STD_INIT(0x486, RT_NULL, RT_NULL),                  /* std,match ID:0x486，hdr 為 - 1 */
        {0x555, 0, 0, 0, 0x7ff, 7,}                                       /* std,match ID:0x555，hdr 為 7，指定設置 7 號過濾表 */
    };
    struct rt_can_filter_config cfg = {5, 1, items}; /* 一共有 5 個過濾表 */
    /* 設置硬件過濾表 */
    res = rt_device_control(can_dev, RT_CAN_CMD_SET_FILTER, &cfg);
    RT_ASSERT(res == RT_EOK);
#endif

    while (1)
    {
        /* hdr 值為 - 1，表示直接從 uselist 鏈表讀取數(shù)據(jù) */
        rxmsg.hdr_index = -1;
        /* 阻塞等待接收信號量 */
        rt_sem_take(&rx_sem, RT_WAITING_FOREVER);
        /* 從 CAN 讀取一幀數(shù)據(jù) */
        rt_device_read(can_dev, 0, &rxmsg, sizeof(rxmsg));
        /* 打印數(shù)據(jù) ID 及內(nèi)容 */
        rt_kprintf("ID:%x", rxmsg.id);
        for (i = 0; i < 8; i++)
        {
            rt_kprintf("%2x", rxmsg.data[i]);
        }
        rt_kprintf("recv end
");
    }
}

int can_sample(void)
{
    struct rt_can_msg msg = {0};
    rt_err_t res;
    rt_size_t  size;
    rt_thread_t thread;
    char can_name[RT_NAME_MAX];

    rt_strncpy(can_name, CAN_DEV_NAME, RT_NAME_MAX);

    /* 查找 CAN 設備 */
    can_dev = rt_device_find(can_name);
    if (!can_dev)
    {
        rt_kprintf("find %s failed!
", can_name);
        return RT_ERROR;
    }

    /* 初始化 CAN 接收信號量 */
    rt_sem_init(&rx_sem, "rx_sem", 0, RT_IPC_FLAG_FIFO);
    /* 設置 CAN 通信的波特率為 500kbit/s*/
    res = rt_device_control(can_dev, RT_CAN_CMD_SET_BAUD, (void *)CAN500kBaud);
    /* 以中斷接收及發(fā)送方式打開 CAN 設備 */
    res = rt_device_open(can_dev, RT_DEVICE_FLAG_INT_TX | RT_DEVICE_FLAG_INT_RX);

    RT_ASSERT(res == RT_EOK);
    /* 創(chuàng)建數(shù)據(jù)接收線程 */
    thread = rt_thread_create("can_rx", can_rx_thread, RT_NULL, 2056, 25, 10);
    if (thread != RT_NULL)
    {
        rt_thread_startup(thread);
    }
    else
    {
        rt_kprintf("create can_rx thread failed!
");
    }

    msg.id = 0x78;              /* ID 為 0x78 */
    msg.ide = RT_CAN_STDID;     /* 標準格式 */
    msg.rtr = RT_CAN_DTR;       /* 數(shù)據(jù)幀 */
    msg.len = 8;                /* 數(shù)據(jù)長度為 8 */
    /* 待發(fā)送的 8 字節(jié)數(shù)據(jù) */
    msg.data[0] = 0x00;
    msg.data[1] = 0x11;
    msg.data[2] = 0x22;
    msg.data[3] = 0x33;
    msg.data[4] = 0x44;
    msg.data[5] = 0x55;
    msg.data[6] = 0x66;
    msg.data[7] = 0x77;
    /* 發(fā)送一幀 CAN 數(shù)據(jù) */
    size = rt_device_write(can_dev, 0, &msg, sizeof(msg));
    if (size == 0)
    {
        rt_kprintf("can dev write data failed!
");
    }

    rt_kprintf("can dev write data OK !
");
    return res;
}
/* 導出到 msh 命令列表中 */
MSH_CMD_EXPORT(can_sample, can device sample);