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1 {{toc/}}
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5
6 = 1. What is MQTT API? =
7
8 {{{MQTT is a publish/subscribe model that runs over TCP/IP sockets or WebSockets. MQTT over WebSockets can be secured with SSL.}}}
9
10
11 = 2. MQTT Features =
12
13 The MQTT protocol runs on TCP / IP or other network protocols and provides an ordered, lossless, bidirectional connection. Features include:
14
15 * The publish / subscribe messaging pattern used, which provides one-to-many messaging for decoupling from the application.
16 * Message-masking mechanism for payload content.
17 * There are three Quality of Service (QoS) for transmitting messages:
18 * At most, messages of this level may be lost or duplicated, and message postings depend on the underlying TCP / IP network. That is: <= 1
19 * At one time, this level will ensure that the message arrives, but the message may be repeated. That is:> = 1
20 * Only once, make sure the message arrives only once. That is: = 1. In some demanding billing systems, you can use this level Data transfer and protocol exchange is minimized (protocol header only 2 bytes) to reduce network traffic
21 * Notification mechanism, notify the transmission of both sides when an exception occurs
22
23
24 = 3. What does this example shows? How it works? =
25
26 The server we use here is ThingSpeak which has an intuitive chart to show the test result for our test.The ThingSpeak IoT service now supports MQTT subscriptions to receive instant updates when [[ThingSpeak>>url:https://thingspeak.com/]] channel gets updated. The method here is general and can be used with other IoT servers for MQTT connection as well.
27
28 [[image:image-20220531135402-1.png]]
29
30 Message Queuing Telemetry Transport
31
32
33 [[image:image-20220531135449-2.png]]
34
35 working principle
36
37
38 [[image:image-20220531135521-3.png]]
39
40 Schematic diagram: uplink.In this section, we will try to program LG01 to uplink data to ThingSpeak. The data flow in this example.We have already tried ① and ② in the above simple LoRa example. Now we will try the step ③ first, after it work as expect, we will integrate these three steps together for a complete uplink example.
41
42
43
44 [[image:image-20220531135607-4.png]]
45
46 Schematic diagram:downlink.In this section, we will try to program LG01 to fetch download data from ThingSpeak, then broadcast this data to local LoRa network. The end node will get this message and check if they need to do something. Similar with Uplink Example, we will first try to do it in PC, then do it in Linux side, and finally integrate it with LoRa.
47
48 MQTT agreement to achieve the need: client and server There are three identities in the MQTT protocol: Publish, Broker (server), Subscribe. Among them, the publisher and the subscriber of the message are all clients, the broker is the server, and the publisher can be both the subscriber and the subscriber. MQTT transmission of information is divided into: Topic and payload in two parts Topic, can be understood as the type of message subscribers Subscribe, you will receive the theme of the message content (payload) The payload, which can be understood as the content of the message, refers to the specific content to be used by the subscribers.
49
50 To use the server, we need to register an account on [[ThingSpeak>>url:https://thingspeak.com/]] . Then create a channel and type the channel info. As shown below, the Channel ID is the unique ID to store our data in [[ThingSpeak>>url:https://thingspeak.com/]] .
51
52
53 = 4. Preparation =
54
55 == 4.1 Hardware ==
56
57 1. [[image:image-20220531135650-5.png]](((
58 Listening on the LoRa wireless channel, while there is new LoRa packet arrives, parse it and send out to IoT Server.
59
60
61
62 )))
63 1. [[~[~[image:https://wiki.dragino.com/images/thumb/4/4a/1.png/400px-1.png~|~|height="216" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:1.png]](((
64 The LoRa End node keeps getting temperature and humidity from the sensor and sends out via LoRa periodically.
65 )))
66
67
68 == 4.2 Software ==
69
70 1. [[4.3.4 version>>url:http://www.dragino.com/downloads/index.php?dir=motherboards/ms14/Firmware/IoT/]]
71 1. [[MQTT_Client>>url:https://github.com/dragino/Arduino-Profile-Examples/tree/master/libraries/Dragino/examples/IoTServer/ThingSpeak/MQTT_Client]]
72 1. [[MQTT_Simple_Server MQTT_Simeple_Server>>url:https://github.com/dragino/Arduino-Profile-Examples/tree/master/libraries/Dragino/examples/LoRa/MQTT_Simple_Server]]
73 1. [[DHTlib>>url:https://github.com/goodcheney/Lora/blob/patch-1/Lora%20Shield/Examples/DHTlib.zip]]
74
75
76
77 == 4.3 Server(For example) ==
78
79 * [[ThingSpeak>>url:https://thingspeak.com/]]
80
81
82 == 4.4 Configure IoT Server ==
83
84 * Need this keys:
85
86 1. [[~[~[image:https://wiki.dragino.com/images/thumb/b/bc/Server1.png/400px-Server1.png~|~|height="185" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:Server1.png]](((
87 Channel ID,Write API Key
88 )))
89 1. [[~[~[image:https://wiki.dragino.com/images/thumb/e/e2/Server2.png/400px-Server2.png~|~|height="128" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:Server2.png]](((
90 Account->My Profile,MQTT API Key
91 )))
92 1. (((
93 [[~[~[image:https://wiki.dragino.com/images/thumb/f/f3/IOT_Configure1.png/400px-IOT_Configure1.png~|~|alt="IOT Configure1.png" height="132" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:IOT_Configure1.png]]
94 )))
95
96
97 == 4.5 Configure LG01 settings ==
98
99 Tips:Please confirm that your LG01 version is 4.3.3.
100
101 [[~[~[image:https://wiki.dragino.com/images/thumb/e/eb/LG01_Version.png/400px-LG01_Version.png~|~|height="219" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:LG01_Version.png]]
102
103 Overview
104
105 [[~[~[image:https://wiki.dragino.com/images/thumb/f/f6/MQTT_LG01_Configure_1.png/400px-MQTT_LG01_Configure_1.png~|~|height="281" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_LG01_Configure_1.png]]
106
107 Senosor->IOT Server
108
109 [[~[~[image:https://wiki.dragino.com/images/thumb/6/64/MQTT_LG01_Configure_2.png/400px-MQTT_LG01_Configure_2.png~|~|height="152" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_LG01_Configure_2.png]]
110
111 MQTT->Configure MQTT Server
112
113 [[~[~[image:https://wiki.dragino.com/images/thumb/6/6a/MQTT_LG01_Configure_3.png/400px-MQTT_LG01_Configure_3.png~|~|height="91" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_LG01_Configure_3.png]]
114
115 MQTT->MQTT Channel
116
117 [[~[~[image:https://wiki.dragino.com/images/thumb/3/36/MQTT_LG01_Configure_4.png/400px-MQTT_LG01_Configure_4.png~|~|height="257" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_LG01_Configure_4.png]]
118
119 Sensor->LoRa/LoraWAN
120
121 [[~[~[image:https://wiki.dragino.com/images/thumb/6/61/MQTT_LG01_Configure_5.png/400px-MQTT_LG01_Configure_5.png~|~|height="230" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_LG01_Configure_5.png]]
122
123 Configure network access.Network->Internet Access
124
125
126 == 4.6 Try MQTT API call with LG01 Linux command ==
127
128 === 4.6.1 Input the command at the console ===
129
130 1. [[~[~[image:https://wiki.dragino.com/images/8/84/3_1.png~|~|height="99" width="93"~]~]>>url:https://wiki.dragino.com/index.php/File:3_1.png]](((
131 Open this Application.
132 )))
133 1. [[~[~[image:https://wiki.dragino.com/images/thumb/d/d7/3_2.png/400px-3_2.png~|~|height="230" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:3_2.png]](((
134 Input passward(dragino).After into the console.
135 )))
136 1. [[~[~[image:https://wiki.dragino.com/images/thumb/5/5d/3_5.png/400px-3_5.png~|~|height="310" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:3_5.png]](((
137 First, we need to make sure the LG01 has internet access. We can log in the SSH and ping an Internet address and see if it get through. As below
138 )))
139 1. [[~[~[image:https://wiki.dragino.com/images/thumb/6/63/3_3.png/400px-3_3.png~|~|height="213" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:3_3.png]](((
140 LG01 has built-in Linux tool mosquitto. It is a very powerful tool for http communication. We can use this tool to handle MQTT API call in LG01. Input this command and replace your keys.
141 )))
142 1. [[~[~[image:https://wiki.dragino.com/images/thumb/3/35/3_4.png/500px-3_4.png~|~|height="180" width="500"~]~]>>url:https://wiki.dragino.com/index.php/File:3_4.png]](((
143 Go to Server check out result.We success to use LG01 to uplink data to ThingSpeak,the mosquitto_pub command is executed in the Linux side, finally, we will have to call mosquitto_pub command with sensor data variable in Arduino side. This is through the process class in Arduino and we will show it in the final sketch.
144 )))
145
146 * This command:
147
148 {{{mosquitto_pub -h mqtt.thingspeak.com -p 1883 -u dragino -P UZ4NGHKJMKS9WR5E -i dragino_Client -t channels/399171/publish/A4NNF6G8G63JOIUV -m "field1=23.5&field2=57.5&status=MQTTPUBLISH"
149 }}}
150
151 * Need replace:
152
153 {{{UZ4NGHKJMKS9WR5E //MQTT API
154 399171 //Channel ID
155 A4NNF6G8G63JOIUV //Write API Key
156 }}}
157
158
159 === 4.6.2 Input the command at the console(LG01 new version:4.3.4) ===
160
161 1. [[~[~[image:https://wiki.dragino.com/images/8/84/3_1.png~|~|height="99" width="93"~]~]>>url:https://wiki.dragino.com/index.php/File:3_1.png]](((
162 Open this Application.
163 )))
164 1. [[~[~[image:https://wiki.dragino.com/images/thumb/6/6e/MQTT_Command_2.png/400px-MQTT_Command_2.png~|~|height="76" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_Command_2.png]](((
165 Check the settings.
166 )))
167 1. [[~[~[image:https://wiki.dragino.com/images/thumb/8/8d/MQTT_Command_1.png/400px-MQTT_Command_1.png~|~|height="343" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_Command_1.png]](((
168 input this command.
169 )))
170 1. [[~[~[image:https://wiki.dragino.com/images/thumb/d/de/MQTT_Command_3.png/400px-MQTT_Command_3.png~|~|height="207" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_Command_3.png]](((
171 Check the result.
172 )))
173
174 == 4.7 Updata data to Server(Through MQTT) ==
175
176 * This version of Sketch implements these features:
177
178 1. Read the LG01 configuration information from Linux.
179 1. Receive the LoRa node data and store the data in the /tmp/iot/channels
180 1. Send reply after then receive LoRa node data.
181 1. Sketch will write active content to /tmp/iot/status periodically (every 5 minutes).(Watchdog feature)
182
183
184 1. [[~[~[image:https://wiki.dragino.com/images/thumb/8/82/MQTT_Sketch_2.png/400px-MQTT_Sketch_2.png~|~|height="233" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_Sketch_2.png]](((
185 Open the sketch [[MQTT_Simple_Server>>url:https://github.com/dragino/Arduino-Profile-Examples/tree/master/libraries/Dragino/examples/LoRa/MQTT_Simple_Server]].(Board:Dragino Yun + UNO or LG01/OLG01,Port:Network ports.)and upload.
186 )))
187 1. [[~[~[image:https://wiki.dragino.com/images/thumb/7/73/MQTT_Sketch2.png/400px-MQTT_Sketch2.png~|~|height="540" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_Sketch2.png]](((
188 Open Serial monitor.
189 )))
190 1. [[~[~[image:https://wiki.dragino.com/images/thumb/9/98/MQTT_Sketch_1.png/400px-MQTT_Sketch_1.png~|~|height="261" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_Sketch_1.png]](((
191 Open the Sketch [[MQTT_Client>>url:https://github.com/dragino/Arduino-Profile-Examples/tree/master/libraries/Dragino/examples/IoTServer/ThingSpeak/MQTT_Client]]. (Board:Arduino/Genuino Uno.Port:Serial ports.)and upload.
192 )))
193 1. [[~[~[image:https://wiki.dragino.com/images/thumb/3/3d/MQTT_Sketch3.png/400px-MQTT_Sketch3.png~|~|height="371" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_Sketch3.png]](((
194 Open Serial monitor.
195 )))
196 1. Go to IoT Server to check the result.
197 1. (((
198 [[~[~[image:https://wiki.dragino.com/images/thumb/4/43/MQTT_result_1.png/400px-MQTT_result_1.png~|~|alt="MQTT result 1.png" height="181" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_result_1.png]]
199 )))
200 1. (((
201 [[~[~[image:https://wiki.dragino.com/images/thumb/7/70/MQTT_result_2.png/400px-MQTT_result_2.png~|~|alt="MQTT result 2.png" height="190" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_result_2.png]]
202 )))
203
204 = 5. FAQ =
205
206 == 5.1 Configure to support general mqtt server ==
207
208 First, try to run **mosquitto_pub** in Linux console to send a data to MQTT server.
209
210 For example: for ThingSpeak, a MQTT publish command is:
211
212 {{{mosquitto_pub -h mqtt.thingspeak.com -p 1883 -u dragino -P QZXTAKE88V3S7O2J -i dragino_Client -t channels/200893/publish/B9Z0R25QNVEBKIFY -m "field1=34&field2=89&status=MQTTPUBLISH"
213 }}}
214
215 What now we need to put in the LG01 is how to combine this command.
216
217 1. LG01 web console -> Sensor -> MQTT
218 1. Choose general Server
219 1. [[~[~[image:https://wiki.dragino.com/images/thumb/e/ea/MQTT_Configure1.png/600px-MQTT_Configure1.png~|~|height="367" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_Configure1.png]](((
220 Refer to your server to fill in.
221 )))
222 1. [[~[~[image:https://wiki.dragino.com/images/0/07/MQTT_Configure2.png~|~|height="93" width="538"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_Configure2.png]](((
223 Ex:ThingSpeak Server
224 )))
225
226 According to MQTT commands: mosquitto_pub, we need to put
227
228 * server[-h] : mqtt.thingspeak.com
229 * port[-p] : 1883
230 * User Name[-u]: dragino
231 * Password[-P]:QZXTAKE88V3S7O2J
232 * Client ID[-i]: dragino_Client
233 * topic_format[-t]: channels/CHANNEL/publish/WRITE_API
234 * data_format[-m]: DATA&status=MQTTPUBLISH
235
236 In the mqtt script, the upper **CHANNEL** will be replaced by the parameter (remote channel in IoT server). and the **WRITE_API** will be replaced by the settings in write api key. the **DATA** will be replaced by the value stored in the /var/iot/channels/LOCAL_CHANNEL file.
237
238 MQTT script will keep checking the files in /var/iot/channels/ . If it find a match Local channel, then the MQTT script will send out the data of this local channel to a remote channel according to the setting above.
239
240 User can also enable MQTT debug in the LG01 ~-~-> IoT Server settings and run logread in Linux console to see how the mqtt command is compose. below is an example:
241
242 [[~[~[image:https://wiki.dragino.com/images/thumb/8/81/MQTT_Configure3.png/600px-MQTT_Configure3.png~|~|height="114" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_Configure3.png]]
243
244 MQTT Logread example
245
246
247 == 5.2 What is Watchdog feature? ==
248
249 LG01 for 4.3.3 version,we have added watchdog feature. In order to avoid the gateway running process will get stuck. So add writing action on every times.
250
251 * [[~[~[image:https://wiki.dragino.com/images/thumb/f/f2/Wathcdog.png/400px-Wathcdog.png~|~|height="184" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:Wathcdog.png]](((
252 Enable Sensor->Micro-Controller settings
253 )))
254 * [[~[~[image:https://wiki.dragino.com/images/thumb/8/82/MQTT_Sketch_2.png/400px-MQTT_Sketch_2.png~|~|height="233" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:MQTT_Sketch_2.png]](((
255 Open the sketch [[MQTT_Simple_Server>>url:https://github.com/dragino/Arduino-Profile-Examples/tree/master/libraries/Dragino/examples/LoRa/MQTT_Simple_Server]].(Board:Dragino Yun + UNO or LG01/OLG01,Port:Network ports.)and upload.
256 )))
257 * [[~[~[image:https://wiki.dragino.com/images/2/21/Loop.png~|~|height="181" width="388"~]~]>>url:https://wiki.dragino.com/index.php/File:Loop.png]](((
258 Each time the function loops, it uses the watchdog function once.
259 )))
260 * [[~[~[image:https://wiki.dragino.com/images/thumb/3/35/Dog.png/400px-Dog.png~|~|height="161" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:Dog.png]](((
261 Open SSH and check watchdog result.If the result change constantly,the feature enable successfully.
262 )))
263 * [[~[~[image:https://wiki.dragino.com/images/thumb/a/ac/Checkdog.png/400px-Checkdog.png~|~|height="222" width="400"~]~]>>url:https://wiki.dragino.com/index.php/File:Checkdog.png]](((
264 If the time doesnt's change,you can refer it to calculate for checking status.
265 )))
266
267 == ==
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