RT-Thread-drv_rtc.c alarm 的实现RT-Thread问答社区

drv_rtc.c alarm 的实现

发布于 2020-08-05 18:28:21 浏览：2907 订阅该版

1. 在RTT提供RTC alarm.c文件是缺少两个命令字的实现的。分别为
- `RT_DEVICE_CTRL_RTC_SET_ALARM`，
- `RT_DEVICE_CTRL_RTC_GET_ALARM`。

2. 分析alarm文件实现方法，可见由一个事件集IPC同步控制alarm的主线程。

```c
/** \brief rtc alarm service thread entry
 *
 */
static void rt_alarmsvc_thread_init(void *param)
{
    rt_uint32_t recv;

_container.current = RT_NULL;

while (1)
    {
        if (rt_event_recv(&_container.event, 0xFFFF,
                          RT_EVENT_FLAG_OR | RT_EVENT_FLAG_CLEAR,
                          RT_WAITING_FOREVER, &recv) == RT_EOK)
        {
            alarm_update(recv);
        }
    }
}
```

3. 然后就找到发送事件同步函数代码

```c
void rt_alarm_update(rt_device_t dev, rt_uint32_t event)
{
    rt_event_send(&_container.event, 1);
}

```

4.这样，只要在驱动drv_rtc.c添加相应的配置代码，实验alarm功能即可完成alarm.c的功能。配合stm32cubemx，生成相关代码。并在MDK上调试通过，采用中断方式响应。通过后，再移植到STUDIO上即可。

5.drv_rtc.c添加设置与查询函数

```c
static rt_err_t rt_rtc_control(rt_device_t dev, int cmd, void *args)
{
    rt_err_t result = RT_EOK;
    RT_ASSERT(dev != RT_NULL);
    switch (cmd)
    {
    case RT_DEVICE_CTRL_RTC_GET_TIME:
        *(rt_uint32_t *)args = get_rtc_timestamp();
        LOG_D("RTC: get rtc_time %x\n", *(rt_uint32_t *)args);
        break;

case RT_DEVICE_CTRL_RTC_SET_TIME:
        if (set_rtc_time_stamp(*(rt_uint32_t *)args))
        {
            result = -RT_ERROR;
        }
        LOG_D("RTC: set rtc_time %x\n", *(rt_uint32_t *)args);
        break;

case RT_DEVICE_CTRL_RTC_SET_ALARM:
        if (set_rtc_alarm_stamp(*(struct rt_rtc_wkalarm *)args))
       {
           result = -RT_ERROR;
       }
       LOG_D("RTC: set rtc_alarm tme : hour: %d , min: %d , sec:  %d \n", *(struct rt_rtc_wkalarm *)args->tm_hour,*(struct rt_rtc_wkalarm *)args->tm_min,*(struct rt_rtc_wkalarm *)args->tm_sec);

break;

case RT_DEVICE_CTRL_RTC_GET_ALARM:
        *(struct rt_rtc_wkalarm *)args = get_rtc_alarm_stamp();

LOG_D("RTC: get rtc_alarm time : hour: %d , min: %d , sec:  %d \n", *(struct rt_rtc_wkalarm *)args->tm_hour,*(struct rt_rtc_wkalarm *)args->tm_min,*(struct rt_rtc_wkalarm *)args->tm_sec);

break;
    }

return result;
}
```

6.对应的子函数的实现 
```c
static rt_err_t set_rtc_alarm_stamp(struct rt_rtc_wkalarm wkalarm)
{
    RTC_AlarmTypeDef sAlarm = {0};

//struct tm *p_tm;

//p_tm = localtime(&time_stamp);

if(wkalarm.enable == RT_FALSE)
    {
        if (HAL_RTC_DeactivateAlarm(&RTC_Handler,RTC_ALARM_A) != HAL_OK)
           {
               return -RT_ERROR;
           }

LOG_D("stop rtc alarm.");

}else {
        /** Enable the Alarm A
        */
        sAlarm.AlarmTime.Hours = wkalarm.tm_hour;
        sAlarm.AlarmTime.Minutes = wkalarm.tm_min;
        sAlarm.AlarmTime.Seconds = wkalarm.tm_sec;
        sAlarm.AlarmTime.DayLightSaving = RTC_DAYLIGHTSAVING_NONE;
        sAlarm.AlarmTime.StoreOperation = RTC_STOREOPERATION_RESET;
        sAlarm.AlarmMask = RTC_ALARMMASK_DATEWEEKDAY;
        sAlarm.AlarmDateWeekDaySel = RTC_ALARMDATEWEEKDAYSEL_DATE;
        sAlarm.AlarmDateWeekDay = 1;
        sAlarm.Alarm = RTC_ALARM_A;
        if (HAL_RTC_SetAlarm_IT(&RTC_Handler, &sAlarm, RTC_FORMAT_BIN) != HAL_OK)
        {
            return -RT_ERROR;
        }
        LOG_D("set rtc alarm.");

}
    return RT_EOK;

}

/**
  * @brief This function handles RTC alarms A and B interrupt through EXTI line 17.
  */
void RTC_Alarm_IRQHandler(void)
{
  /* USER CODE BEGIN RTC_Alarm_IRQn 0 */

/* USER CODE END RTC_Alarm_IRQn 0 */
  HAL_RTC_AlarmIRQHandler(&RTC_Handler);
  /* USER CODE BEGIN RTC_Alarm_IRQn 1 */

/* USER CODE END RTC_Alarm_IRQn 1 */
}

void HAL_RTC_AlarmAEventCallback(RTC_HandleTypeDef *hrtc)
{
    rt_alarm_update(0,0);
}

struct rt_rtc_wkalarm get_rtc_alarm_stamp(void)
{
    RTC_AlarmTypeDef sAlarm = {0};

//struct tm tm_new = {0};
    struct rt_rtc_wkalarm wkalarm;

if (HAL_RTC_GetAlarm(&RTC_Handler, &sAlarm,RTC_ALARM_A, RTC_FORMAT_BIN) != HAL_OK)
   {
        LOG_D("get rtc alarm fail!.");
   }

wkalarm.tm_sec  = sAlarm.AlarmTime.Seconds;
    wkalarm.tm_min = sAlarm.AlarmTime.Minutes;
    wkalarm.tm_hour = sAlarm.AlarmTime.Hours;

LOG_D("get rtc alarm.");
   // return mktime(&tm_new);
    return wkalarm;
}
```

7.我是采用中断方式响应事件，上面代码添加中断处理函数。在回调里实现发送事件。

```c
/**
  * @brief This function handles RTC alarms A and B interrupt through EXTI line 17.
  */
void RTC_Alarm_IRQHandler(void)
{
  /* USER CODE BEGIN RTC_Alarm_IRQn 0 */

/* USER CODE END RTC_Alarm_IRQn 0 */
  HAL_RTC_AlarmIRQHandler(&RTC_Handler);
  /* USER CODE BEGIN RTC_Alarm_IRQn 1 */

/* USER CODE END RTC_Alarm_IRQn 1 */
}

void HAL_RTC_AlarmAEventCallback(RTC_HandleTypeDef *hrtc)
{
    rt_alarm_update(0,0);
}

```

8.由于采用了中断，所以初始化要增加中继使能

```c
    /* RTC interrupt DeInit */
    HAL_NVIC_SetPriority(RTC_Alarm_IRQn, 0, 0);
    HAL_NVIC_EnableIRQ(RTC_Alarm_IRQn);
```

9.再配合王老师应用例程，测试即可。
https://club.rt-thread.org/ask/question/e07b2690efcee5cf.html