使用软件包dht11，读取数据为0，怎么回事？

发布于 2020-01-24 12:45:19 浏览：3573 订阅该版

![01.png](/uploads/202001/24/124259c57wzlud3w7z65bl.png)
![02.png](/uploads/202001/24/124316apacvwa3fga5wi5z.png)

代码我参考了事例：[https://github.com/murphyzhao/dht11_rtt/blob/master/dht11_sample.c](https://github.com/murphyzhao/dht11_rtt/blob/master/dht11_sample.c)
我只是引脚修改成了：#define DHT11_DATA_PIN    GET_PIN(A, 8)

如何修改才能读取到数值？

如下main全部代码：
```c
/*
 * Copyright (c) 2006-2019, RT-Thread Development Team
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Change Logs:
 * Date           Author       Notes
 * 2019-09-09     RT-Thread    first version
 */

#include <rtthread.h>
#include <board.h>
#define DBG_TAG "main"
#define DBG_LVL DBG_LOG
#include "sensor.h"
#include "sensor_dallas_dht11.h"
/* PLEASE DEFINE the LED0 pin for your board, such as: PA5 */
//#define LED0_PIN GET_PIN(C, 13)
//#define OUT11_PIN GET_PIN(A,  11)
#define DHT11_DATA_PIN    GET_PIN(A, 8)
int main(void)
{

//int count = 1;
    /* set LED0 pin mode to output */
    //rt_pin_mode(LED0_PIN, PIN_MODE_OUTPUT);
    //rt_pin_mode(OUT11_PIN,PIN_MODE_INPUT);
    /*
    while (count++)
    {
        rt_thread_delay(1000);
        LOG_D("thread run count : %d_%d <br>", count,rt_pin_read(OUT11_PIN));
        rt_pin_write(LED0_PIN, PIN_HIGH);
        rt_thread_delay(1000);
        rt_pin_write(LED0_PIN, PIN_LOW);
    }
    */

return RT_EOK;
}
static void read_temp_entry(void *parameter)
{
    rt_device_t dev = RT_NULL;
    struct rt_sensor_data sensor_data;
    rt_size_t res;
    rt_uint8_t get_data_freq = 1; /* 1Hz */

dev = rt_device_find("temp_dht11");
    if (dev == RT_NULL)
    {
        return;
    }

if (rt_device_open(dev, RT_DEVICE_FLAG_RDWR) != RT_EOK)
    {
        rt_kprintf("open device failed!<br>");
        return;
    }

rt_device_control(dev, RT_SENSOR_CTRL_SET_ODR, (void *)(&get_data_freq));

while (1)
    {
        res = rt_device_read(dev, 0, &sensor_data, 1);

if (res != 1)
        {
            rt_kprintf("read data failed! result is %d<br>", res);
            rt_device_close(dev);
            return;
        }
        else
        {
            if (sensor_data.data.temp >= 0)
            {
                uint8_t temp = (sensor_data.data.temp & 0xffff) >> 0;      // get temp
                uint8_t humi = (sensor_data.data.temp & 0xffff0000) >> 16; // get humi
                rt_kprintf("temp:%d, humi:%d<br>" ,temp, humi);
            }
        }

rt_thread_delay(1000);
    }
}

static int dht11_read_temp_sample(void)
{
    rt_thread_t dht11_thread;

dht11_thread = rt_thread_create("dht_tem",
                                     read_temp_entry,
                                     RT_NULL,
                                     1024,
                                     RT_THREAD_PRIORITY_MAX / 2,
                                     20);
    if (dht11_thread != RT_NULL)
    {
        rt_thread_startup(dht11_thread);
    }

return RT_EOK;
}
INIT_APP_EXPORT(dht11_read_temp_sample);

static int rt_hw_dht11_port(void)
{
    struct rt_sensor_config cfg;

cfg.intf.user_data = (void *)DHT11_DATA_PIN;
    rt_hw_dht11_init("dht11", &cfg);

return RT_EOK;
}
INIT_COMPONENT_EXPORT(rt_hw_dht11_port);
```