Wiki source code of Application Note : Communicate with Different Sensors ----- RS485-LN / RS485-BL

Last modified by Karry Zhuang on 2024/07/11 11:58

version	line-number	content
57.14	1	Table of Contents:
6.2	2
	3	{{toc/}}
	4
41.2	5
	6
	7
	8
	9
60.12	10	= 1. Introduction =
1.1	11
57.6	12
1.2	13	This article provide the examples for RS485-LN to connect to different type of RS485 sensors.
1.1	14
38.2	15
60.12	16	== 1.1 Example 1: Connect to Leak relay and VFD ==
60.5	17
1.1	18
1.2	19	This instruction is provided by Xavier Florensa Berenguer from [[NORIA GRUPO DE COMPRAS>>url:http://www.gruponovelec.com/]]. It is to show how to use RS485-LN to connect to Relay and VFD and communicate with Mobile. The structure is like below:
1.1	20
60.5	21
60.10	22	[[image:image-20220527091852-1.png\|\|height="547" width="994"]]
1.1	23
60.12	24	Connection
1.1	25
1.18	26
10.2	27	[[image:image-20220527091942-2.png]](% style="display:none" %)
	28
60.12	29	Connection
1.1	30
10.2	31
57.15	32	(% style="color:blue" %)Related documents:
1.1	33
60.13	34	* System Structure: [[Solar Pump with Dragino>>url:http://www.dragino.com/downloads/index.php?dir=RS485-LN/Application_Note/Relay_VFD/\|\|_mstmutation="1" style="background-color: rgb(255, 255, 255);"]]
	35
60.1	36	* Explanation on how to integrate to Node-red and to the Mobile Phone, and with link to the Github code: [[Configure Manual>>url:http://www.dragino.com/downloads/index.php?dir=RS485-LN/Application_Note/Relay_VFD/\|\|_mstmutation="1" style="background-color: rgb(255, 255, 255);"]]
60.13	37
1.2	38	* [[Video Demo>>url:https://www.youtube.com/watch?v=TAFZ5eaf-MY&t=6s&ab_channel=XavierFlorensaBerenguer]]
1.1	39
62.2	40
60.12	41	== 1.2 Example 2: Connect to Pulse Counter ==
1.1	42
57.7	43
1.2	44	This instruction is provided by Xavier Florensa Berenguer from [[NORIA GRUPO DE COMPRAS>>url:http://www.gruponovelec.com/]]. It is to show how to use RS485-LN to connect to Pulse Counter and communicate with Mobile. This example and example 2 compose the structure for a farm IoT solution. The structure is like below:
1.1	45
57.7	46
60.10	47	[[image:image-20220527092058-3.png\|\|height="552" width="905"]]
1.1	48
60.12	49	Connection
1.1	50
1.18	51
60.10	52	[[image:image-20220527092146-4.png\|\|height="507" width="906"]]
1.2	53
60.12	54	Connection
1.2	55
41.12	56
57.15	57	(% style="color:blue" %)Related documents:
	58
60.1	59	* Configure Document: [[Pickdata MIO40 water pulse counter to LoRa with Dragino RS485-LN>>url:http://www.dragino.com/downloads/index.php?dir=RS485-LN/Application_Note/Pulse-Counter/\|\|_mstmutation="1"]]
60.13	60
1.2	61	* [[Dragino Solution in Farm>>url:http://www.dragino.com/downloads/index.php?dir=RS485-LN/Application_Note/&file=Dragino%20on%20Farms.pptx]]
	62
62.2	63
60.12	64	== 1.3 Example 3: Use RS485-LN with energy meters ==
1.2	65
60.12	66	=== 1.3.1 OverView ===
57.8	67
60.12	68
1.5	69	(((
60.4	70	(% style="color:red" %)Note：The specifications of each energy meter are different, please refer to your own energy meter specifications.
1.5	71	)))
1.2	72
1.5	73	(((
1.2	74	This example describes a single-phase meter.This is the connection between the RS485-LN and the energy meter.
1.5	75	)))
1.2	76
13.2	77	[[image:image-20220527092419-5.png]]
1.2	78
60.12	79	Connection1
1.2	80
13.2	81
1.19	82	(((
57.16	83	(% style="color:blue" %)How to connect with Energy Meter：
57.8	84
	85
1.19	86	)))
1.2	87
1.19	88	(((
1.2	89	Follow the instructions of the electric energy meter to connect the phase line and the neutral line, and then connect 485A+ and 485B- to RS485A and RA485B of RS485-LN respectively.
1.19	90	)))
1.2	91
1.19	92	(((
1.2	93	The RS485-LN can be powered by 7 ~~ 24V DC power source. Connection as below
1.19	94	)))
1.2	95
1.19	96	(((
60.13	97	Power Source VIN to RS485-LN VIN+
1.19	98	)))
1.2	99
1.19	100	(((
60.13	101	Power Source GND to RS485-LN VIN-
1.19	102	)))
1.2	103
1.19	104	(((
1.2	105	Once there is power, the RS485-LN will be on.
1.19	106	)))
1.2	107
13.2	108	[[image:image-20220527092514-6.png]]
1.2	109
60.12	110	Connection2
1.2	111
	112
20.2	113	[[image:image-20220527092555-7.png]]
1.12	114
60.12	115	Connection3
1.2	116
	117
60.12	118	=== 1.3.2 How to use the parameters of the energy meter and MODBUS commands ===
57.21	119
1.2	120
1.7	121	If the user needs to read the parameters of the electric energy meter and use the modbus command,please refer to the appendix of the MODBUS communication protocol in the user manual of the energy meter.
1.2	122
51.2	123	[[image:image-20220601143257-10.png]]
1.2	124
20.2	125
57.8	126	(% style="color:blue" %)Example:(%%) AT+COMMAND1=01 03 00 00 00 01 84 0A
1.2	127
	128	* The first byte : slave address code (=001～247)
60.13	129
1.2	130	* The second byte : read register value function code
60.13	131
1.2	132	* 3rd and 4th bytes: start address of register to be read
60.13	133
1.2	134	* 5th and 6th bytes: Number of registers to read
60.13	135
1.2	136	* 7th and 8th bytes: CRC16 checksum from bytes 1 to 6.
	137
1.12	138	(((
57.8	139
	140
	141
1.2	142	How to parse the reading of the return command of the parameter：
	143
57.8	144	(% style="color:blue" %)Example:(%%) RETURN1：01 03 02 08 FD 7E 05
1.8	145	)))
1.2	146
	147	* The first byte ARD: slave address code (=001～254)
60.13	148
1.2	149	* The second byte: Return to read function code
60.13	150
1.2	151	* 3rd byte: total number of bytes
60.13	152
1.2	153	* 4th～5th bytes: register data
60.13	154
1.2	155	* The 6th and 7th bytes: CRC16 checksum
60.13	156
1.2	157	* 08 FD is register data. Use short integer 16 bits to convert to decimal, get 2301, then 230.1V is the voltage.
	158
62.2	159
60.12	160	=== 1.3.3 How to configure RS485-LN and parse output commands ===
1.2	161
57.8	162
1.2	163	RS485-LN provides two configuration methods: AT COMMAND and DOWNLINK.
	164
20.2	165
60.13	166	==== 1.3.3.1 via AT COMMAND ====
57.21	167
1.2	168
57.8	169	First, we can use (% style="color:blue" %)AT+CFGDEV(%%) to get the return value, and we can also judge whether the input parameters are correct.
	170
1.8	171	(((
1.2	172	If the configured parameters and commands are incorrect, the return value is not obtained.
60.6	173
	174
1.8	175	)))
1.2	176
50.2	177	[[image:image-20220601143201-9.png]]
1.2	178
60.12	179	AT COMMAND
1.2	180
20.2	181
1.8	182	(% class="box infomessage" %)
	183	(((
60.1	184	(% _mstmutation="1" %)AT+DATACUTx (%%): This command defines how to handle the return from AT+COMMANDx, max reture length is 40 bytes. AT+DATACUTx=a,b,c
1.8	185	)))
1.2	186
41.15	187	a: length for the return of AT+COMMAND
1.2	188
41.15	189	b: 1: grab valid value by byte, max 6 bytes; 2: grab valid value by bytes section, max 3 sections.
1.2	190
41.15	191	c: define the position for valid value.
1.2	192
50.2	193	[[image:image-20220601143115-8.png]]
1.2	194
60.12	195	AT COMMAND
1.2	196
20.2	197
1.2	198	PAYLOAD is available after the valid value is intercepted.
	199
48.2	200	[[image:image-20220601143046-7.png]]
1.2	201
60.12	202	AT COMMAND
1.2	203
20.2	204
1.2	205	You can get configured PAYLOAD on TTN.
	206
52.2	207	[[image:image-20220601143519-1.png]]
1.8	208
1.12	209	(((
60.12	210	AT COMMAND
1.12	211	)))
1.2	212
1.12	213	(((
1.13	214
	215	)))
	216
	217	(((
57.8	218	(% style="color:blue" %)Example:
39.3	219
57.18	220	(% style="color:red" %)CMD1:(%%) Read current data with MODBUS command. address: 0x03 AT+COMMAND1= 01 03 00 03 00 01,1
1.12	221	)))
1.2	222
1.12	223	(((
57.8	224	RETURN1: 01 03 02 00 02 39 85 00 00(return data)
1.12	225	)))
1.2	226
1.12	227	(((
57.8	228	AT+DATACUT1: 9,1,4+5+6+7 Take the return value 00 02 39 85 as the valid value of reading current data and used to splice payload.
39.3	229
	230
1.12	231	)))
1.2	232
1.12	233	(((
57.18	234	(% style="color:red" %)CMD2: (%%)Read voltage data with MODBUS command. address: 0x00 AT+COMMAND2= 01 03 00 00 00 01,1
1.12	235	)))
1.2	236
1.12	237	(((
57.8	238	RETURN2: 01 03 02 08 DC BE 1D(return data)
1.12	239	)))
1.2	240
1.12	241	(((
57.8	242	AT+DATACUT2: 7,1,4+5 Take the return value 08 DC as the valid value of reading voltage data and used to splice payload.
39.3	243
	244
1.12	245	)))
1.2	246
1.12	247	(((
57.18	248	(% style="color:red" %)CMD3:(%%) Read total active energy data with MODBUS command. address: 0x0031 AT+COMMAND3= 01 03 00 31 00 02,1
1.12	249	)))
1.2	250
1.12	251	(((
57.9	252	RETURN3: 01 03 04 00 00 00 44 FA 00(return data)
1.12	253	)))
1.2	254
1.12	255	(((
57.8	256	AT+DATACUT3: 9,1,4+5+6+7 Take the return value 00 00 00 44 as the valid value of reading total active energy data and used to splice payload.
1.12	257	)))
1.2	258
1.12	259	(((
57.8	260	Payload: 01 00 02 39 85 08 DC 00 00 00 44
1.12	261	)))
1.2	262
47.2	263	[[image:image-20220601142936-6.png]]
1.2	264
	265	AT COMMAND
	266
20.2	267
60.6	268	(% style="color:blue" %)01 is device address,00 02 is the current, 08 DC is the voltage,00 00 00 44 is the total active energy.
1.2	269
41.17	270
53.2	271	[[image:image-20220601143642-2.png]]
1.8	272
1.2	273	AT COMMAND
	274
	275
60.13	276	==== 1.3.3.2 via LoRaWAN DOWNLINK ====
1.8	277
57.8	278
21.2	279	[[image:image-20220527093358-15.png]]
1.2	280
1.9	281	(((
60.12	282	DOWNLINK
1.9	283	)))
1.2	284
1.9	285
	286	(((
60.7	287	(% style="color:blue" %)Type Code 0xAF
1.9	288	)))
1.2	289
1.9	290	(((
4.3	291	(% class="box infomessage" %)
	292	(((
1.2	293	0xAF downlink command can be used to set AT+COMMANDx or AT+DATACUTx.
1.9	294	)))
4.3	295	)))
1.2	296
1.9	297	(((
57.26	298	(% style="color:red" %)Note: if user use AT+COMMANDx to add a new command, he also need to send AT+DATACUTx downlink.
1.9	299	)))
1.2	300
1.9	301	(((
1.2	302	Format: AF MM NN LL XX XX XX XX YY
1.9	303	)))
1.2	304
1.9	305	(((
1.2	306	Where:
1.9	307	)))
1.2	308
1.9	309	(((
1.2	310	MM: the ATCOMMAND or AT+DATACUT to be set. Value from 01 ~~ 0F,
1.9	311	)))
1.2	312
1.9	313	(((
1.2	314	NN: 0: no CRC; 1: add CRC-16/MODBUS ; 2: set the AT+DATACUT value.
1.9	315	)))
1.2	316
1.9	317	(((
1.2	318	LL: The length of AT+COMMAND or AT+DATACUT command
1.9	319	)))
1.2	320
1.9	321	(((
1.2	322	XX XX XX XX: AT+COMMAND or AT+DATACUT command
1.9	323	)))
1.2	324
1.9	325	(((
1.2	326	YY: If YY=0, RS485-LN will execute the downlink command without uplink; if YY=1, RS485-LN
1.9	327	)))
1.2	328
1.9	329	(((
1.2	330	will execute an uplink after got this command.
1.9	331	)))
1.2	332
60.13	333
1.9	334	(((
57.11	335	(% style="color:blue" %)Example:
1.9	336	)))
1.2	337
1.9	338	(((
39.4	339	AF 03 01 06 0A 05 00 04 00 01 00: Same as AT+COMMAND3=0A 05 00 04 00 01,1
1.9	340	)))
1.2	341
57.2	342	[[image:image-20220601144149-6.png]]
1.2	343
60.12	344	DOWNLINK
1.2	345
1.8	346
54.2	347	[[image:image-20220601143803-3.png]]
1.2	348
60.12	349	DOWNLINK
1.2	350
1.8	351
57.2	352	[[image:image-20220601144053-5.png]]
1.2	353
60.12	354	DOWNLINK
1.2	355
1.8	356
55.2	357	[[image:image-20220601143921-4.png]]
1.2	358
60.12	359	DOWNLINK
1.2	360
1.15	361
46.2	362	[[image:image-20220601142805-5.png]]
1.2	363
60.12	364	DOWNLINK
1.2	365
57.21	366
60.12	367	=== 1.3.4 How to configure and output commands for RS485 to USB ===
1.2	368
60.2	369
1.13	370	(((
1.2	371	This step is not necessary, it is just to show how to use a normal RS485 to USB adapter to connect to the meter to check the input and output. This can be used to test the connection and RS485 command of the meter without RS485-LN.
1.13	372	)))
1.2	373
1.13	374	(((
1.2	375	First, connect the A+ and A- of the USB to the 485 A and 485 B of the energy meter.
1.13	376	)))
1.2	377
1.13	378	(((
1.2	379	Open the serial port debugging, set the send and receive to HEX.
1.13	380	)))
1.2	381
1.13	382	(((
1.2	383	Baud rate: 9600
1.13	384	)))
1.2	385
1.13	386	(((
1.2	387	check digit: Even
1.13	388	)))
1.2	389
27.2	390	[[image:image-20220527093708-21.png]]
1.2	391
60.12	392	USB
1.2	393
1.13	394
29.2	395	[[image:image-20220527093747-22.png]]
1.2	396
60.12	397	USB
1.2	398
1.13	399
41.24	400
1.13	401	(((
1.2	402	The configuration command is consistent with the AT command, input the hexadecimal command directly into the serial port, and the serial port will output the command.
1.13	403	)))
1.2	404
1.13	405	(((
57.11	406	(% style="color:blue" %)Example: (%%)input：01 03 00 31 00 02 95 c4
1.13	407	)))
1.2	408
1.13	409	(((
4.6	410	output：01 03 04 00 00 00 42 7A 02
57.11	411
	412
1.13	413	)))
1.2	414
29.2	415	[[image:image-20220527093821-23.png]]
1.2	416
60.12	417	USB
1.2	418
29.2	419
60.12	420	=== 1.3.5 How to configure multiple devices and modify device addresses ===
1.2	421
57.11	422
1.2	423	If users need to read the parameters of multiple energy meters, they need to modify the device address, because the default device address of each energy meter is 01.
	424
1.14	425	(((
1.15	426	(((
1.2	427	Set the device address according to the parameters in the appendix of the MODBUS communication protocol.
1.14	428	)))
1.15	429	)))
1.2	430
42.2	431	[[image:image-20220601142044-1.png]]
1.2	432
30.2	433
57.11	434	(% style="color:blue" %)Example(%%): These two meters are examples of setting parameters and device addresses.
1.2	435
60.8	436
31.2	437	[[image:image-20220527093950-25.png]]
1.2	438
57.4	439
32.2	440	[[image:image-20220527094028-26.png]]
1.2	441
57.12	442
1.14	443	(((
1.16	444	(((
1.2	445	First of all, since the default device address of the energy meter is 01, the configuration of two energy meters will conflict, so we first connect an energy meter and configure the device address.
1.14	446	)))
1.16	447	)))
1.2	448
1.14	449	(((
1.16	450	(((
57.27	451	We can use (% style="color:blue" %)AT+CFGDEV(%%) to set the device address.
1.14	452	)))
1.16	453	)))
1.2	454
1.14	455	(((
1.16	456	(((
1.2	457	We modify the device address 01 of the first energy meter to 02.
1.14	458	)))
1.16	459	)))
1.2	460
43.2	461	[[image:image-20220601142354-2.png]]
1.2	462
57.12	463
35.2	464	(% class="box infomessage" %)
	465	(((
	466	AT+CFGDEV:01 10 00 61 00 01 02 00 02,1
	467	)))
1.2	468
60.12	469	* 01: device adaress
1.2	470
60.12	471	* 10: function code
1.2	472
	473	* 00 61：Register address
	474
	475	* 00 01：Number of Registers
	476
	477	* 02：Number of bytes
	478
	479	* 00 02：Modified device address
	480
	481	* 1：Check code
	482
	483	The device address setting of the energy meter is complete.
	484
	485	Another energy meter is a single active energy meter with a floating-point format.
	486
	487	Its default device address is 01, and the following are the parameters for configuring two energy meters.
	488
44.2	489	[[image:image-20220601142452-3.png]]
1.2	490
	491
45.2	492	[[image:image-20220601142607-4.png]]
35.2	493
57.12	494
57.21	495	(% style="color:blue" %)PAYLOAD: 01 08 DF 43 62
1.2	496
	497	* 08 DF is the valid value of the meter with device address 02.
	498	* 43 62 is the valid value of the meter with device address 01.
	499
60.10	500	(% style="display:none" %) (%%)
60.8	501
	502
1.2	503	== 1.4 Example 4: Circuit Breaker Remote Open Close ==
	504
	505
57.12	506	This instruction is provided by Xavier Florensa Berenguer from [[NORIA GRUPO DE COMPRAS>>url:http://www.gruponovelec.com/]]. It is to show how to use RS485-LN to connect to SCHNEIDER SMART and Monitor and control your cabinet remotely with no wires and with Dragino RS485-LN LoRaWAN technology.
	507
	508	The structure is like below:
	509
36.2	510	[[image:image-20220527094330-30.png]]
1.2	511
60.13	512	Connection
1.2	513
	514
60.1	515	* Configure Documen: [[Circuit Breaker Remote Open Close>>url:http://www.dragino.com/downloads/index.php?dir=RS485-LN/Application_Note/Circuit_Breaker_Remote_Open_Close/\|\|_mstmutation="1"]]
57.12	516
62.2	517
1.2	518	== 1.5 Example 5: SEM Three Energy Meter with RS485-BL or RS485-LN ==
	519
57.12	520
1.2	521	This instruction is provided by Xavier Florensa Berenguer from [[NORIA GRUPO DE COMPRAS>>url:http://www.gruponovelec.com/]]. It is to show how to use RS485-BL to connect to SEM Three Energy Meter and send the data to mobile phone for remote minitor. The structure is like below:
	522
60.1	523	* Configure Document For RS485-BL: [[Connect to SEM Three>>url:http://www.dragino.com/downloads/index.php?dir=LoRa_End_Node/RS485-BL/Application_Note/&file=Dragino%20RS485BL%20and%20pickdata%20SEM%20Three%20v1.pdf\|\|_mstmutation="1" style="background-color: rgb(255, 255, 255);"]]
60.13	524
60.1	525	* Configure Document for RS485-LN: [[Connect to SEM Three>>url:http://www.dragino.com/downloads/index.php?dir=RS485-LN/Application_Note/SEM_Three_Energy_Meter/&file=SEM%20three%20and%20Dragino%20RS485-LN%20v1.pdf\|\|_mstmutation="1"]]
1.2	526
62.2	527
57.14	528	== 1.6 Example 6: CEM C31 485-T1-MID Energy Meter with RS485-LN ==
1.2	529
57.13	530
1.2	531	This instruction is provided by Xavier Florensa Berenguer from [[NORIA GRUPO DE COMPRAS>>url:http://www.gruponovelec.com/]]. It is to show how to use RS485-LN to connect to CEM C31 485-T1-MID and send the data for remote minitor. The structure is like below:
	532
60.1	533	* Configure Document For RS485-LN: [[CEM C31 485-T1-MID>>url:http://www.dragino.com/downloads/index.php?dir=RS485-LN/Application_Note/ELECTRICAL%20CABINET/&file=ELECTRICAL%20CABINET%20READINGS.pdf\|\|_mstmutation="1" style="background-color: rgb(255, 255, 255);"]]
1.2	534
62.2	535
57.14	536	== 1.7 Example 7: Schneider Electric PLC M221 with RS485-BL ==
1.2	537
57.13	538
38.1	539	[[image:image-20220527094556-31.png]]
1.2	540
61.1	541
1.2	542	Network Structure
	543
61.1	544	* [[Reference Instruction>>url:https://www.dragino.com/downloads/index.php?dir=RS485-LN/Application_Note/Schneider%20Electric%20PLC/]]
57.13	545
61.1	546
62.2	547	== 1.8 Example 8: This sketch is supposed to test Dragino RS485-BL (Modbus master), using an Arduino UNO as a Modbus slave. ==
	548
	549
61.1	550	This sketch uses 4 registers: some of them can be set by Dragino with a command, another is used to store value from a DS18B20 temperature sensor, or a random generated number. All data is 16bit uint, but the sketch shows also how to represent booleans and negative numbers.
	551
	552	In the next days I will be adding more documentation, but I think it already explains users how to build their own modbus sensor to pair with Dragino RS485-BL.
	553
	554	This is released the code under GNU LGPL licence on Github:
	555
	556	[[https:~~/~~/github.com/zorbaproject/ArduinoModbusForDraginoRS485>>url:https://github.com/zorbaproject/ArduinoModbusForDraginoRS485]]
	557
62.3	558
	559	== 1.9 Example 9: RS485-LN and ultrasonic flow meter transmission data ==
	560
	561
	562	It shows how to use RS485-LN to connect to an ultrasonic flow meter and read the data from the ultrasonic flow meter.
	563
	564
79.2	565	Need to prepare RS485-LN, recharger, Electric wire
62.3	566
79.2	567	[[image:1720669739434-926.png]] [[image:1720669744315-613.png]]
	568
	569
	570	=== 1.9.1 Setting Ultrasonic Flowmeter ===
	571
	572
	573	Adjust the M option corresponding to the ultrasonic flowmeter as follows
	574
79.4	575	M52 sets RS485 Port M62 sets 9600, none, 1 M63 sets automatic
79.2	576
79.5	577	[[image:1720669933691-331.png]][[image:1720669981767-254.png\|\|height="550" width="412"]][[image:1720670003601-544.png\|\|height="550" width="412"]]
79.2	578
	579
	580	=== 1.9.2 Setting Dragino RS485-LN ===
	581
	582
	583	The RS485-LN wiring port is as shown below. Connect the power supply and RS485 A/B line according to the diagram.
	584
	585	[[image:1720670016539-422.png]][[image:1720670019136-658.png]]
	586
	587
	588	=== 1.9.3 Connect the RS485-LN to Ultrasonic Flowmeter ===
	589
	590
	591	According to the instructions of the ultrasonic flow meter, 26 and 27 are the + and - of RS485, corresponding to the A and B ports of RS485.
	592
	593	[[image:1720670035661-234.png]][[image:1720670041974-372.png\|\|height="417" width="436"]]
	594
	595
	596	=== 1.9.4 Full wiring example ===
	597
	598
	599	The yellow wire connects port 26 and port A of RS485-LN.
	600
	601	The green wire connects port 27 and port B of RS485-LN.
	602
	603	[[image:1720670079781-764.png]]
	604
	605
	606	=== 1.9.5 How to read ultrasonic flow meter data via RS485 ===
	607
	608
	609	[[image:1720670090204-634.png]]
	610
	611
	612	For example, I want to read Positive
	613
	614	Through M02, we can see that the POS data is 54.9862
	615
	616	[[image:1720670103571-173.png]][[image:1720670108127-723.png\|\|height="597" width="645"]]
	617
	618	Registers are 9-12, so the read command is AT+CFGDEV=01 03 00 08 00 04,1(,1 is used for automatic complement)
	619
	620	[[image:1720670123955-149.png]]
	621
	622
	623	00 36 00 00 is the integer of the read value
	624
	625	78 79 3f 7c is a decimal, but it needs to be converted and parsed into floating point. The parsing order is CDAB, which is 3f 7c 78 79
	626
	627	Conversion and parsing website:http:~/~/www.speedfly.cn/tools/hexconvert/
	628
	629	[[image:1720670134750-980.png]]
	630
	631

Wiki source code of Application Note : Communicate with Different Sensors ----- RS485-LN / RS485-BL

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