概述

本文介绍如何在 睿擎工业开发平台 中创建并运行 硬件定时器 示例工程。通过驱动 TL3576 平台内置硬件定时器，演示了利用 RT-Thread 设备驱动框架进行硬件定时器操作的完整流程，支持单次定时和周期定时两种模式。

硬件定时器简介

硬件定时器是 RT-Thread 中用于管理片上定时器资源的核心框架。它提供设置定时模式（单次/周期）、配置超时时间、注册超时回调函数、读取当前计数值及停止定时器等功能，支持通过标准化接口实现硬件定时器的精确控制与事件管理。

查询手册获取硬件定时器资源

根据 TL3576 技术参考手册（TRM）可知：

• TL3576 内部集成多路硬件定时器，本示例使用 hwtimer5
• 支持单次（oneshot）和周期（period）两种工作模式
• 定时精度可达微秒级，超时时间可通过参数动态配置

构建与烧录

创建工程点击展开

1. 依次点击 “文件” -> “新建” -> "RT-Thread RuiChing App 项目"。

   

2. 在弹出新建向导中选择 开发版 、BSP: 、示例 、 调试器/下载器。选择好之后点击 “完成”。

   

3. 点击 “完成” 后，等待工程创建完成。

   

4. 创建完成。

   

构建工程点击展开

1. 单击工程使工程进入 Active-Debug 模式。

   

2. 点击工具栏上的构建按钮进行工程编译。

   

3. 构建成功后，会显示构建成功的信息。

   

固件下载点击展开

1. 固化驱动

   

2. 固化 APP

   

核心示例代码

硬件定时器示例相关 API

• rt_device_find：查找硬件定时器设备；
• rt_device_open：打开设备；
• rt_device_set_rx_indicate：注册超时回调函数；
• rt_device_control + HWTIMER_CTRL_MODE_SET：设置定时模式（单次/周期）；
• rt_device_write：设置超时时间并启动定时器；
• rt_device_control + HWTIMER_CTRL_STOP：停止定时器；

• HWTIMER 示例

#define TEST_HWTIMER_NAME   "hwtimer5"      // 硬件定时器设备名

static rt_err_t timeout_cb(rt_device_t dev, rt_size_t size)// hwtimer 中断回调函数
{
    rt_kprintf("[hwtimer] timeout! callback size=%d, tick=%lu\n",
               size, rt_tick_get());
    return RT_EOK;
}

static void hwtimer_test(int argc, char *argv[])// HWTIMER 测试入口函数
{
    rt_device_t hw_dev = RT_NULL;
    rt_hwtimerval_t timeout;
    rt_hwtimer_mode_t mode;
    rt_err_t err;
    const char *dev_name;
    rt_uint32_t sec  = 2;
    rt_uint32_t usec = 500000;

    if (argc < 3)
    {
        rt_kprintf("Usage:\n");
        rt_kprintf("  hwtimer_test <hwtimer5> <oneshot|period> [sec] [usec]\n");
        rt_kprintf("  hwtimer_read  <hwtimer5>\n");
        rt_kprintf("  hwtimer_stop  <hwtimer5>\n");
        return;
    }

    dev_name = argv[1];

    if (rt_strcmp(argv[2], "oneshot") == 0)
        mode = HWTIMER_MODE_ONESHOT;
    else if (rt_strcmp(argv[2], "period") == 0)
        mode = HWTIMER_MODE_PERIOD;
    else
    {
        rt_kprintf("Invalid mode! Use 'oneshot' or 'period'.\n");
        return;
    }

    if (argc >= 4)
        sec  = atoi(argv[3]);
    if (argc >= 5)
        usec = atoi(argv[4]);

    hw_dev = rt_device_find(dev_name);// 查找硬件定时器设备
    if (hw_dev == RT_NULL)
    {
        rt_kprintf("Can't find device: %s (enable BSP_USING_HWTIMER5)\n", dev_name);
        return;
    }

    err = rt_device_open(hw_dev, RT_DEVICE_FLAG_RDWR);
    if (err != RT_EOK)
    {
        rt_kprintf("Open %s failed, err=%d\n", dev_name, err);
        return;
    }

    rt_device_set_rx_indicate(hw_dev, timeout_cb);// 注册超时回调

    err = rt_device_control(hw_dev, HWTIMER_CTRL_MODE_SET, &mode);// 设置定时模式
    if (err != RT_EOK)
    {
        rt_kprintf("Set mode failed, err=%d\n", err);
        rt_device_close(hw_dev);
        return;
    }

    timeout.sec  = sec;
    timeout.usec = usec;

    rt_kprintf("[hwtimer] %s start: mode=%s, timeout=%d.%06d sec\n",
               dev_name,
               (mode == HWTIMER_MODE_ONESHOT) ? "ONESHOT" : "PERIOD",
               timeout.sec, timeout.usec);

    if (rt_device_write(hw_dev, 0, &timeout, sizeof(timeout)) != sizeof(timeout))// 启动定时器
    {
        rt_kprintf("Start %s failed\n", dev_name);
        rt_device_close(hw_dev);
        return;
    }

    if (mode == HWTIMER_MODE_PERIOD)
    {
        rt_thread_mdelay(10000);
        rt_kprintf("[hwtimer] stopping %s after 10s...\n", dev_name);
        rt_device_control(hw_dev, HWTIMER_CTRL_STOP, RT_NULL);// 停止周期定时器
    }
    else
    {
        rt_thread_mdelay(sec * 1000 + usec / 1000 + 1000);
    }

    rt_device_close(hw_dev);
    rt_kprintf("[hwtimer] %s test finished.\n", dev_name);
}

• HWTIMER 读取

static void hwtimer_read(int argc, char *argv[])
{
    rt_device_t hw_dev;
    rt_hwtimer_t *timer;
    rt_base_t level;
    rt_uint32_t cnt;
    rt_uint32_t remain_us;

    if (argc < 2)
    {
        rt_kprintf("Usage: hwtimer_read <hwtimer5>\n");
        return;
    }

    hw_dev = rt_device_find(argv[1]);// 查找硬件定时器设备
    if (hw_dev == RT_NULL)
    {
        rt_kprintf("Can't find device: %s\n", argv[1]);
        return;
    }

    if (rt_device_open(hw_dev, RT_DEVICE_FLAG_RDWR) != RT_EOK)
    {
        rt_kprintf("Open %s failed\n", argv[1]);
        return;
    }

    timer = (rt_hwtimer_t *)hw_dev;
    if (timer->ops == RT_NULL || timer->ops->count_get == RT_NULL)
    {
        rt_kprintf("[hwtimer] count_get not supported\n");
        rt_device_close(hw_dev);
        return;
    }

    level = rt_hw_interrupt_disable();
    cnt = timer->ops->count_get(timer);
    rt_hw_interrupt_enable(level);

    cnt = (rt_uint32_t)(timer->freq * timer->period_sec) - cnt;
    remain_us = cnt * 1000000 / timer->freq;

    rt_kprintf("[hwtimer] %s count=%lu remain=%lu us\n",
               argv[1], (unsigned long)cnt, (unsigned long)remain_us);

    rt_device_close(hw_dev);
}

• HWTIMER 停止

static void hwtimer_stop(int argc, char *argv[])
{
    rt_device_t hw_dev;
    rt_err_t err;

    if (argc < 2)
    {
        rt_kprintf("Usage: hwtimer_stop <hwtimer5>\n");
        return;
    }

    hw_dev = rt_device_find(argv[1]);// 查找硬件定时器设备
    if (hw_dev == RT_NULL)
    {
        rt_kprintf("Can't find device: %s\n", argv[1]);
        return;
    }

    err = rt_device_open(hw_dev, RT_DEVICE_FLAG_RDWR);
    if (err != RT_EOK)
    {
        rt_kprintf("Open %s failed, err=%d\n", argv[1]);
        return;
    }

    err = rt_device_control(hw_dev, HWTIMER_CTRL_STOP, RT_NULL);
    if (err == RT_EOK)
        rt_kprintf("[hwtimer] %s stopped.\n", argv[1]);
    else
        rt_kprintf("[hwtimer] stop %s failed, err=%d\n", argv[1], err);

    rt_device_close(hw_dev);
}

运行示例

操作步骤

1. 将程序下载到开发板
2. 打开串口终端连接开发板
3. 在终端输入 hwtimer_test hwtimer5 period 启动周期定时（默认 2.5s 超时，运行 10s 后自动停止）
4. 定时器超时后自动打印日志，程序自动退出
5. 输入 hwtimer_test hwtimer5 oneshot 1 0 启动 1 秒单次定时
6. 等待超时回调触发后程序自动退出
7. 先启动周期定时器，再输入 hwtimer_read hwtimer5 查看剩余计数值

预期结果

验证 TL3576 开发板的硬件定时器外设基本功能正常，三种命令行为如下：

RT-Thread 终端

msh />hwtimer_test hwtimer5 period
[hwtimer] hwtimer5 start: mode=PERIOD, timeout=2.500000 sec
[hwtimer] timeout! callback size=8, tick=81920713
[hwtimer] timeout! callback size=8, tick=81923188
[hwtimer] timeout! callback size=8, tick=81925663
[hwtimer] timeout! callback size=8, tick=81928138
[hwtimer] stopping hwtimer5 after 10s...
[hwtimer] hwtimer5 test finished.

RT-Thread 终端

msh />hwtimer_test hwtimer5 oneshot 1 0
[hwtimer] hwtimer5 start: mode=ONESHOT, timeout=1.000000 sec
[hwtimer] timeout! callback size=8, tick=82134778
[hwtimer] hwtimer5 test finished.

RT-Thread 终端

msh />hwtimer_test hwtimer5 period
[hwtimer] hwtimer5 start: mode=PERIOD, timeout=2.500000 sec
[hwtimer] timeout! callback size=8, tick=82162085
[hwtimer] timeout! callback size=8, tick=82164560
[hwtimer] timeout! callback size=8, tick=82167035
[hwtimer] timeout! callback size=8, tick=82169510
[hwtimer] stopping hwtimer5 after 10s...
[hwtimer] hwtimer5 test finished.
msh />hwtimer_read hwtimer5
[hwtimer] hwtimer5 count=57593280 remain=85 us
msh />hwtimer_stop hwtimer5
[hwtimer] hwtimer5 stopped.