ESP32/ESP8266のMicroPythonのDHTセンサーデータをホストPCのpythonでMQTT受信する

2020/3/6

ESP32/ESP8266 MicroPython DHT Python MQTT test

ESP32/ESP8266 MicroPython DHT Python MQTT test

概要

ESP32/ESP8266のMicroPythonのDHTセンサーデータをホストPCのpythonでMQTT受信する。MicroPython側が送信側、ホストPCのpythonが受信側になる。

接続

Grove-DHT11センサーをGrove-Base-Shield経由でGrove-D5-Slotに接続すると 以下のように接続したことになる。

Grove D5 solot

Arduino-Pin	ESP8266
D5	IO04
D6	IO05(NOT USED)
VCC	3.3V
GND	GND

受信側Pythonスクリプト

PY_MQTT_DHT_recv.py

  #!usr/bin/env python
  # -*- coding: utf-8 -*-

  # receving DHT11 sensor data from ESP_MicroPython via MQTT

  import paho.mqtt.client as mqtt
  import json

  def on_connect(client, userdata, flags, respons_code):
      topic = 'DHT11'
      print('watch %s' % topic)
      client.subscribe(topic)

  def on_message(client, userdata, msg):
      #print(msg.topic + ' ' + str(msg.payload))
      print(msg.topic+':')
      parsed = json.loads(str(msg.payload))
      print('time: '+parsed['time'])
      print('Temperature: '+str(parsed['Temperature']))
      print('Humidity: '+str(parsed['humidity']))
      print('---------------------------')


  client = mqtt.Client()

  client.on_connect = on_connect
  client.on_message = on_message

  #client.connect('5.196.95.208', 1883, keepalive=60)
  client.connect('test.mosquitto.org', 1883, keepalive=60)

  client.loop_forever()
  

該当ライブラリーは以下でインストールする：

  pip install paho-mqtt
  

送信側micropythonスクリプト

MQTT_DHT_send.py
以下は自分の環境に合わせる：
ssid = 'your_ssid'
password = 'your_passwd'

  # boot.py
  ssid = 'your_ssid'
  password = 'your_passwd'
  mqtt_server = '5.196.95.208'

  # Complete project details at https://RandomNerdTutorials.com

  import time
  from umqttsimple import MQTTClient
  import ubinascii
  import machine
  import micropython
  import network
  import esp
  esp.osdebug(None)
  import gc
  gc.collect()

  client_id = ubinascii.hexlify(machine.unique_id())

  last_message = 0
  #message_interval = 5
  counter = 0

  station = network.WLAN(network.STA_IF)

  station.active(True)
  station.connect(ssid, password)

  while station.isconnected() == False:
    pass

  print('Connection successful')
  print(station.ifconfig())
  #===========================================
  from machine import RTC
  import utime
  import ntptime
  rtc = RTC()
  ntptime.settime() # setup time by remote NTP server

  def get_jst():
     tm = utime.localtime(utime.time()) # UTC now
     jst = str(tm[0])+'/'+str(tm[1])+'/'+str(tm[2])+' '+str((tm[3]+9)%24)+':'+str(tm[4])+':'+str(tm[5])
     return jst

  #===========================================
  import ujson
  import dht
  from machine import Pin
  d = dht.DHT11(Pin(4))

  message_interval = 1 # sec

  def connect_and_subscribe():
    global client_id, mqtt_server, topic_sub
    client = MQTTClient(client_id, mqtt_server)
  #  client.set_callback(sub_cb)
    client.connect()
  #  client.subscribe(topic_sub)
  #  print('Connected to %s MQTT broker, subscribed to %s topic' % (mqtt_server, topic_sub))
    print('Connected to MQTT broker:'+mqtt_server)
    return client

  def restart_and_reconnect():
    print('Failed to connect to MQTT broker. Reconnecting...')
    time.sleep(10)
    machine.reset()

  try:
    client = connect_and_subscribe()
  except OSError as e:
    restart_and_reconnect()

  while True:
    try:
  #    client.check_msg()
      if (time.time() - last_message) > message_interval:
        dict = {}
        dict['time'] = get_jst()
        dict['sensorType'] = 'DHT11'
        d.measure()
        dict['Temperature'] = d.temperature()
        dict['humidity'] = d.humidity()
        msg = ujson.dumps(dict)
        topic = 'DHT11'
        print(topic+':'+msg) # debug
        client.publish(topic, msg)
        last_message = time.time()
        counter += 1
    except OSError as e:
      restart_and_reconnect()

  

実行画面

ESP32/SP8266のMicroPython側は MQTT_DHT_send.py を実行し、
受信側は 「python PY_MQTT_DHT_recv.py」を実行すると
以下のような実行画面になる：

ホストＰＣのシェル画面：

$ python PY_MQTT_DHT_recv.py 
  watch DHT11
  DHT11:
  time: 2020/3/6 21:56:0
  Temperature: 18
  Humidity: 13
  ---------------------------
  DHT11:
  time: 2020/3/6 21:56:2
  Temperature: 18
  Humidity: 13
  ---------------------------
  ...
  

おまけ(pythonの受信/送信サンプル)

送信サンプル：
PY_publisher.py

  #!usr/bin/env python
  # -*- coding: utf-8 -*-

  import paho.mqtt.client as mqtt

  client = mqtt.Client()

  #client.connect('5.196.95.208', 1883, keepalive=60)
  client.connect('test.mosquitto.org', 1883, keepalive=60)

  for n in range(24):
     client.publish('test/topic', 'hello world #'+str(n))

  

受信側サンプル：
PY_subsriber.py

  #!usr/bin/env python
  # -*- coding: utf-8 -*-

  import paho.mqtt.client as mqtt

  def on_connect(client, userdata, flags, respons_code):
      topic = 'test/topic'
      print('watch %s' % topic)
      client.subscribe(topic)

  def on_message(client, userdata, msg):
      print(msg.topic + ' ' + str(msg.payload))

  client = mqtt.Client()

  client.on_connect = on_connect
  client.on_message = on_message

  #client.connect('5.196.95.208', 1883, keepalive=60)
  client.connect('test.mosquitto.org', 1883, keepalive=60)

  client.loop_forever()

  

参考情報

paho-mqtt 1.5.0

MQTT.js

MQTT test server @mosquitto.org
The server listens on the following ports:
1883 : MQTT, unencrypted
8883 : MQTT, encrypted
8884 : MQTT, encrypted, client certificate required
8080 : MQTT over WebSockets, unencrypted
8081 : MQTT over WebSockets, encrypted

MQTT test server @eclipse.org
This is a public test MQTT broker service.
It currently listens on the following ports:
1883 : MQTT over unencrypted TCP
8883 : MQTT over encrypted TCP
80 : MQTT over unencrypted WebSockets (note: URL must be /mqtt )
443 : MQTT over encrypted WebSockets (note: URL must be /mqtt )

10 Free Public & Private MQTT Brokers(For Testing & Production)
http://www.mqtt-dashboard.com/
MQTT is a machine-to-machine (M2M)/"Internet of Things"

ESP32/ESP8266のMicroPythonでMQTTを使ってみた
MQTT(over WebSocket)をブラウザーで使ってみた

MicroPython – Getting Started with MQTT on ESP32/ESP8266

ＥＳＰ３２－ＤｅｖＫｉｔＣ　ＥＳＰ－ＷＲＯＯＭ－３２開発ボード
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以上