魔镜项目添加DHT11模块读取温度

续前面魔镜项目，地址：http://www.jianshu.com/p/696cb979b62a

1.新增文件：
controllers/thsensor.php
内容：

<?php
$myfile = fopen("../th/wth.th", "r") or die("Unable to open file!");
echo fread($myfile,filesize("../th/wth.th"));
fclose($myfile);
?>

2.dht11传感器控制端接树莓派第11针：
01 ---- 3.3v | 5v ---- 02
03 ---- | 5v ---- 04
。。。。。。。。。。。。。。
11 ---- GPIO0|GPIO1 ---- 12

3.新增文件
py/dht11.py
内容:

#!/usr/bin/python

import RPi.GPIO as GPIO
import time

channel = 17

while True:
    data = []
    j = 0

    GPIO.setmode(GPIO.BCM)

    time.sleep(1)

    GPIO.setup(channel, GPIO.OUT)

    GPIO.output(channel, GPIO.LOW)
    time.sleep(0.02)
    GPIO.output(channel, GPIO.HIGH)

    GPIO.setup(channel, GPIO.IN)

    while GPIO.input(channel) == GPIO.LOW:
        continue

    while GPIO.input(channel) == GPIO.HIGH:
        continue

    while j < 40:
        k = 0
        while GPIO.input(channel) == GPIO.LOW:
            continue
    
        while GPIO.input(channel) == GPIO.HIGH:
            k += 1
            if k > 100:
                break
    
        if k < 8:
            data.append(0)
        else:
            data.append(1)

        j += 1

    print "sensor is working."
    print data

    humidity_bit = data[0:8]
    humidity_point_bit = data[8:16]
    temperature_bit = data[16:24]
    temperature_point_bit = data[24:32]
    check_bit = data[32:40]

    humidity = 0
    humidity_point = 0
    temperature = 0
    temperature_point = 0
    check = 0

    for i in range(8):
        humidity += humidity_bit[i] * 2 ** (7 - i)
        humidity_point += humidity_point_bit[i] * 2 ** (7 - i)
        temperature += temperature_bit[i] * 2 ** (7 - i)
        temperature_point += temperature_point_bit[i] * 2 ** (7 - i)
        check += check_bit[i] * 2 ** (7 - i)

    tmp = humidity + humidity_point + temperature + temperature_point

    if check == tmp:
        f = file("/var/www/html/th/wth.th","w+")
        li = ['{"temperature":%s,"humidity":%s}' % (temperature, humidity) ]
        f.writelines(li)
        f.close()
    
    time.sleep(10)

    del data[:]
    j = 0
  
    #print "temperature : ", temperature, ", humidity : " , humidity
#else:
    #print "wrong"
    #print "temperature : ", temperature, ", humidity : " , humidity, " check : ", check, " tmp : ", tmp

    GPIO.cleanup()

4.新增文件
js/weather/tem_hum.js 编辑后保存为UTF-8编码
内容：

var tem_hum = {
  dl: config.displayLanguage || 'en',
  temperatureLocation: '.temhum',
  updateInterval: 10000,

}

tem_hum.updateTemHum = function () {
  $.ajax({
    type: 'GET',
    datatype:'jsonp',
    url: 'controllers/thsensor.php',
    success: function (data) {
      // console.info(data);
      var ths = JSON.parse(data);

      if (tem_hum.dl == 'cn') {
        // var thtext = '室内温湿 ' + ths.temperature + '°, ' + ths.humidity + '%';
        var thtext1 = '<div>' + ths.temperature + '°</div><div class="xxsmall">室温</div>'
        var thtext2 = '<div>' + ths.humidity    + '%</div><div class="xxsmall">湿度</div>'
        var thtext  = '<div><span class="th">'+thtext1+'</span> <span class="th" style="width: 20;"></span> <span class="th">'+thtext2+'</span></div>'
      } else {
        var thtext = '当前室内温度:' + ths.temperature + '℃, 湿度:' + ths.humidity + '%';
      }

      $(this.temperatureLocation).updateWithText(thtext, this.fadeInterval);
    }.bind(this),
    error: function () {
      // non-specific error message that should be updated
      console.error('No thsensor results');
    }
  });

}

tem_hum.init = function () {

    this.updateTemHum();

    this.intervalId = setInterval(function () {
        this.updateTemHum();
    }.bind(this), this.updateInterval)

}

5.新增文件：
th/wth.th

{"temperature":26,"humidity":70}

6.修改:
index.php

  最下方<script src="" type=""></script>处，最后面添加：

<script src="js/weather/tem_hum.js" type="text/javascript"></script>

7.脚本开机自启

①在/home/pi/.config目录里创建一个autostart文件夹（如果提示文件夹已存在请直接下一步）

mkdir /home/pi/.config/autostart/

②在/home/pi/.config/autostart目录里创建并编辑dht11.desktop文件

nano /home/pi/.config/autostart/dht11.desktop

③输入以下内容

[Desktop Entry]
Name=dht11
Comment=My Python dht11
Exec=python /var/www/html/py/dht11.py
Terminal=false
MultipleArgs=false
Type=Application
Categories=Application;Development;
StartupNotify=true

8.输入reboot重启