Wiki source code of RS485-LN – RS485 to LoRaWAN Converter

Version 41.7 by Xiaoling on 2022/06/02 16:37

version	line-number	content
3.2	1	(% style="text-align:center" %)
18.2	2	[[image:1653266934636-343.png\|\|height="385" width="385"]]
1.1	3
	4
	5
18.2	6	RS485-LN – RS485 to LoRaWAN Converter User Manual
1.1	7
	8
3.2	9	Table of Contents:
1.1	10
	11
	12
	13
	14
3.2	15	= 1.Introduction =
1.1	16
19.2	17	== 1.1 What is RS485-LN RS485 to LoRaWAN Converter ==
1.1	18
3.2	19	(((
	20	(((
32.3	21	The Dragino RS485-LN is a (% style="color:blue" %)RS485 to LoRaWAN Converter(%%). It converts the RS485 signal into LoRaWAN wireless signal which simplify the IoT installation and reduce the installation/maintaining cost.
3.2	22	)))
2.2	23
3.2	24	(((
32.3	25	RS485-LN allows user to (% style="color:blue" %)monitor / control RS485 devices(%%) and reach extremely long ranges. It provides ultra-long range spread spectrum communication and high interference immunity whilst minimizing current consumption. It targets professional wireless sensor network applications such as irrigation systems, smart metering, smart cities, smartphone detection, building automation, and so on.
3.2	26	)))
2.2	27
3.2	28	(((
32.3	29	(% style="color:blue" %)For data uplink(%%), RS485-LN sends user-defined commands to RS485 devices and gets the return from the RS485 devices. RS485-LN will process these returns according to user-define rules to get the final payload and upload to LoRaWAN server.
3.2	30	)))
2.2	31
3.2	32	(((
32.3	33	(% style="color:blue" %)For data downlink(%%), RS485-LN runs in LoRaWAN Class C. When there downlink commands from LoRaWAN server, RS485-LN will forward the commands from LoRaWAN server to RS485 devices.
32.2	34
32.3	35	(% style="color:blue" %)Demo Dashboard for RS485-LN(%%) connect to two energy meters: [[https:~~/~~/app.datacake.de/dashboard/d/58844a26-378d-4c5a-aaf5-b5b5b153447a>>url:https://app.datacake.de/dashboard/d/58844a26-378d-4c5a-aaf5-b5b5b153447a]]
3.2	36	)))
	37	)))
2.2	38
19.2	39	[[image:1653267211009-519.png\|\|height="419" width="724"]]
2.2	40
32.4	41
3.2	42	== 1.2 Specifications ==
2.2	43
32.6	44
2.2	45	Hardware System:
	46
	47	* STM32L072CZT6 MCU
22.4	48	* SX1276/78 Wireless Chip
2.2	49	* Power Consumption (exclude RS485 device):
19.3	50	** Idle: 32mA@12v
	51	** 20dB Transmit: 65mA@12v
2.2	52
	53	Interface for Model:
	54
19.3	55	* RS485
22.4	56	* Power Input 7~~ 24V DC.
2.2	57
	58	LoRa Spec:
	59
	60	* Frequency Range:
	61	** Band 1 (HF): 862 ~~ 1020 Mhz
	62	** Band 2 (LF): 410 ~~ 528 Mhz
	63	* 168 dB maximum link budget.
	64	* +20 dBm - 100 mW constant RF output vs.
19.3	65	* +14 dBm high efficiency PA.
2.2	66	* Programmable bit rate up to 300 kbps.
	67	* High sensitivity: down to -148 dBm.
	68	* Bullet-proof front end: IIP3 = -12.5 dBm.
	69	* Excellent blocking immunity.
19.3	70	* Low RX current of 10.3 mA, 200 nA register retention.
2.2	71	* Fully integrated synthesizer with a resolution of 61 Hz.
19.3	72	* FSK, GFSK, MSK, GMSK, LoRaTM and OOK modulation.
2.2	73	* Built-in bit synchronizer for clock recovery.
	74	* Preamble detection.
	75	* 127 dB Dynamic Range RSSI.
19.3	76	* Automatic RF Sense and CAD with ultra-fast AFC.
	77	* Packet engine up to 256 bytes with CRC.
2.2	78
41.2	79
3.3	80	== 1.3 Features ==
2.2	81
19.4	82	* LoRaWAN Class A & Class C protocol (default Class C)
2.2	83	* Frequency Bands: CN470/EU433/KR920/US915/EU868/AS923/AU915/IN865/RU864
	84	* AT Commands to change parameters
19.4	85	* Remote configure parameters via LoRa Downlink
2.2	86	* Firmware upgradable via program port
	87	* Support multiply RS485 devices by flexible rules
	88	* Support Modbus protocol
19.4	89	* Support Interrupt uplink (Since hardware version v1.2)
2.2	90
41.3	91
3.3	92	== 1.4 Applications ==
2.2	93
	94	* Smart Buildings & Home Automation
	95	* Logistics and Supply Chain Management
	96	* Smart Metering
	97	* Smart Agriculture
	98	* Smart Cities
	99	* Smart Factory
	100
41.4	101
6.2	102	== 1.5 Firmware Change log ==
2.2	103
19.4	104	[[RS485-LN Image files – Download link and Change log>>url:http://www.dragino.com/downloads/index.php?dir=RS485-LN/]]
2.2	105
32.10	106
4.2	107	== 1.6 Hardware Change log ==
2.2	108
4.2	109	(((
	110	(((
19.4	111	v1.2: Add External Interrupt Pin.
2.2	112
19.4	113	v1.0: Release
32.10	114
	115
4.2	116	)))
	117	)))
2.2	118
20.2	119	= 2. Power ON Device =
2.2	120
6.2	121	(((
20.2	122	The RS485-LN can be powered by 7 ~~ 24V DC power source. Connection as below
2.2	123
20.2	124	* Power Source VIN to RS485-LN VIN+
	125	* Power Source GND to RS485-LN VIN-
2.2	126
20.3	127	(((
20.2	128	Once there is power, the RS485-LN will be on.
20.3	129	)))
2.2	130
20.2	131	[[image:1653268091319-405.png]]
32.11	132
	133
20.2	134	)))
2.2	135
6.2	136	= 3. Operation Mode =
2.2	137
6.2	138	== 3.1 How it works? ==
2.2	139
7.2	140	(((
21.2	141	The RS485-LN is configured as LoRaWAN OTAA Class C mode by default. It has OTAA keys to join network. To connect a local LoRaWAN network, user just need to input the OTAA keys in the network server and power on the RS485-LN. It will auto join the network via OTAA.
32.12	142
	143
7.2	144	)))
2.2	145
7.2	146	== 3.2 Example to join LoRaWAN network ==
2.2	147
6.2	148	Here shows an example for how to join the TTN V3 Network. Below is the network structure, we use [[LG308>>url:http://www.dragino.com/products/lora-lorawan-gateway/item/140-lg308.html]] as LoRaWAN gateway here.
2.2	149
21.2	150	[[image:1653268155545-638.png\|\|height="334" width="724"]]
2.2	151
32.13	152
15.3	153	(((
32.13	154	(((
22.2	155	The RS485-LN in this example connected to two RS485 devices for demonstration, user can connect to other RS485 devices via the same method. The connection is as below:
32.13	156	)))
2.2	157
32.13	158	(((
22.2	159	485A+ and 485B- of the sensor are connected to RS485A and RA485B of RS485-LN respectively.
32.13	160	)))
22.2	161
	162	[[image:1653268227651-549.png\|\|height="592" width="720"]]
	163
15.3	164	(((
22.2	165	The LG308 is already set to connect to [[TTN V3 network >>path:eu1.cloud.thethings.network/]]. So what we need to now is only configure the TTN V3:
15.3	166	)))
2.2	167
15.3	168	(((
22.2	169	Step 1: Create a device in TTN V3 with the OTAA keys from RS485-LN.
15.3	170	)))
2.2	171
15.3	172	(((
22.2	173	Each RS485-LN is shipped with a sticker with unique device EUI:
15.3	174	)))
22.2	175	)))
2.2	176
15.2	177	[[image:1652953462722-299.png]]
2.2	178
15.3	179	(((
22.3	180	(((
2.2	181	User can enter this key in their LoRaWAN Server portal. Below is TTN V3 screen shot:
15.3	182	)))
2.2	183
15.3	184	(((
2.2	185	Add APP EUI in the application.
15.3	186	)))
22.3	187	)))
2.2	188
15.2	189	[[image:image-20220519174512-1.png]]
2.2	190
22.3	191	[[image:image-20220519174512-2.png\|\|height="323" width="720"]]
2.2	192
15.2	193	[[image:image-20220519174512-3.png\|\|height="556" width="724"]]
2.2	194
15.2	195	[[image:image-20220519174512-4.png]]
2.2	196
	197	You can also choose to create the device manually.
	198
15.2	199	[[image:1652953542269-423.png\|\|height="710" width="723"]]
2.2	200
	201	Add APP KEY and DEV EUI
	202
15.2	203	[[image:1652953553383-907.png\|\|height="514" width="724"]]
2.2	204
	205
15.2	206	(((
22.4	207	Step 2: Power on RS485-LN and it will auto join to the TTN V3 network. After join success, it will start to upload message to TTN V3 and user can see in the panel.
15.2	208	)))
2.2	209
15.2	210	[[image:1652953568895-172.png\|\|height="232" width="724"]]
2.2	211
32.14	212
15.5	213	== 3.3 Configure Commands to read data ==
2.2	214
15.5	215	(((
22.4	216	(((
	217	There are plenty of RS485 devices in the market and each device has different command to read the valid data. To support these devices in flexible, RS485-LN supports flexible command set. User can use [[AT Commands>>path:#AT_COMMAND]] or LoRaWAN Downlink Command to configure what commands RS485-LN should send for each sampling and how to handle the return from RS485 devices.
15.5	218	)))
2.2	219
22.4	220	(((
	221	(% style="color:red" %)Note: below description and commands are for firmware version >v1.1, if you have firmware version v1.0. Please check the [[user manual v1.0>>url:http://www.dragino.com/downloads/index.php?dir=RS485-LN/&file=RS485-LN_UserManual_v1.0.1.pdf]] or upgrade the firmware to v1.1
32.15	222
	223
22.4	224	)))
	225	)))
	226
15.5	227	=== 3.3.1 onfigure UART settings for RS485 or TTL communication ===
2.2	228
22.6	229	To use RS485-LN to read data from RS485 sensors, connect the RS485-LN A/B traces to the sensors. And user need to make sure RS485-LN use the match UART setting to access the sensors. The related commands for UART settings are:
2.2	230
32.16	231	(% border="1" style="background-color:#ffffcc; color:green; width:782px" %)
	232	\|(% style="width:128px" %)(((
15.5	233	AT Commands
32.16	234	)))\|(% style="width:305px" %)(((
15.5	235	Description
32.16	236	)))\|(% style="width:346px" %)(((
15.5	237	Example
	238	)))
32.16	239	\|(% style="width:128px" %)(((
15.5	240	AT+BAUDR
32.16	241	)))\|(% style="width:305px" %)(((
15.5	242	Set the baud rate (for RS485 connection). Default Value is: 9600.
32.16	243	)))\|(% style="width:346px" %)(((
15.5	244	(((
2.2	245	AT+BAUDR=9600
15.5	246	)))
2.2	247
15.5	248	(((
2.2	249	Options: (1200,2400,4800,14400,19200,115200)
	250	)))
15.5	251	)))
32.16	252	\|(% style="width:128px" %)(((
15.5	253	AT+PARITY
32.16	254	)))\|(% style="width:305px" %)(((
2.2	255	Set UART parity (for RS485 connection)
32.16	256	)))\|(% style="width:346px" %)(((
15.5	257	(((
2.2	258	AT+PARITY=0
15.5	259	)))
2.2	260
15.5	261	(((
2.2	262	Option: 0: no parity, 1: odd parity, 2: even parity
	263	)))
15.5	264	)))
32.16	265	\|(% style="width:128px" %)(((
15.5	266	AT+STOPBIT
32.16	267	)))\|(% style="width:305px" %)(((
15.5	268	(((
2.2	269	Set serial stopbit (for RS485 connection)
15.5	270	)))
2.2	271
15.5	272	(((
22.6	273
15.5	274	)))
32.16	275	)))\|(% style="width:346px" %)(((
15.5	276	(((
2.2	277	AT+STOPBIT=0 for 1bit
15.5	278	)))
2.2	279
15.5	280	(((
2.2	281	AT+STOPBIT=1 for 1.5 bit
15.5	282	)))
2.2	283
15.5	284	(((
2.2	285	AT+STOPBIT=2 for 2 bits
	286	)))
15.5	287	)))
2.2	288
41.5	289
15.6	290	=== 3.3.2 Configure sensors ===
2.2	291
15.6	292	(((
	293	(((
22.7	294	Some sensors might need to configure before normal operation. User can configure such sensor via PC and RS485 adapter or through RS485-LN AT Commands (% style="color:#4f81bd" %)AT+CFGDEV(%%). Each (% style="color:#4f81bd" %)AT+CFGDEV (%%)equals to send a RS485 command to sensors. This command will only run when user input it and won’t run during each sampling.
15.6	295	)))
22.7	296	)))
2.2	297
15.6	298	(% border="1" style="background-color:#ffffcc; color:green; width:806px" %)
	299	\|AT Commands\|(% style="width:418px" %)Description\|(% style="width:256px" %)Example
	300	\|AT+CFGDEV\|(% style="width:418px" %)(((
2.2	301	This command is used to configure the RS485/TTL devices; they won’t be used during sampling.
	302
15.6	303	AT+CFGDEV=xx xx xx xx xx xx xx xx xx xx xx xx,
2.2	304
15.6	305	mm: 0: no CRC, 1: add CRC-16/MODBUS in the end of this command
	306	)))\|(% style="width:256px" %)AT+CFGDEV=xx xx xx xx xx xx xx xx xx xx xx xx,m
2.2	307
41.6	308
15.6	309	=== 3.3.3 Configure read commands for each sampling ===
2.2	310
15.6	311	(((
35.2	312	During each sampling, we need confirm what commands we need to send to the RS485 sensors to read data. After the RS485 sensors send back the value, it normally include some bytes and we only need a few from them for a shorten payload.
2.2	313
	314	To save the LoRaWAN network bandwidth, we might need to read data from different sensors and combine their valid value into a short payload.
	315
	316	This section describes how to achieve above goals.
	317
35.2	318	During each sampling, the RS485-LN can support 15 commands to read sensors. And combine the return to one or several uplink payloads.
2.2	319
	320
35.2	321	Each RS485 commands include two parts:
2.2	322
35.2	323	~1. What commands RS485-LN will send to the RS485 sensors. There are total 15 commands from AT+COMMAD1, ATCOMMAND2,…, to AT+COMMANDF. All commands are of same grammar.
2.2	324
35.2	325	2. How to get wanted value the from RS485 sensors returns from by 1). There are total 15 AT Commands to handle the return, commands are AT+DATACUT1,AT+DATACUT2,…, AT+DATACUTF corresponding to the commands from 1). All commands are of same grammar.
2.2	326
35.4	327	3. Some RS485 device might has longer delay on reply, so user can use AT+CMDDL to set the timeout for getting reply after the RS485 command is sent. For example AT+CMDDL1=1000 to send the open time to 1000ms
2.2	328
	329
	330	After we got the valid value from each RS485 commands, we need to combine them together with the command AT+DATAUP.
	331
	332
	333	Below are examples for the how above AT Commands works.
	334
	335
35.2	336	AT+COMMANDx : This command will be sent to RS485 devices during each sampling, Max command length is 14 bytes. The grammar is:
	337
	338	(% border="1" style="background-color:#4bacc6; color:white; width:499px" %)
	339	\|(% style="width:496px" %)(((
2.2	340	AT+COMMANDx=xx xx xx xx xx xx xx xx xx xx xx xx,m
	341
	342	xx xx xx xx xx xx xx xx xx xx xx xx: The RS485 command to be sent
	343
	344	m: 0: no CRC, 1: add CRC-16/MODBUS in the end of this command
	345	)))
	346
	347	For example, if we have a RS485 sensor. The command to get sensor value is: 01 03 0B B8 00 02 46 0A. Where 01 03 0B B8 00 02 is the Modbus command to read the register 0B B8 where stored the sensor value. The 46 0A is the CRC-16/MODBUS which calculate manually.
	348
35.2	349	In the RS485-LN, we should use this command AT+COMMAND1=01 03 0B B8 00 02,1 for the same.
2.2	350
	351
	352	AT+DATACUTx : This command defines how to handle the return from AT+COMMANDx, max return length is 45 bytes.
	353
35.2	354	(% border="1" style="background-color:#4bacc6; color:white; width:725px" %)
	355	\|(% style="width:722px" %)(((
2.2	356	AT+DATACUTx=a,b,c
	357
	358	* a: length for the return of AT+COMMAND
	359	* b:1: grab valid value by byte, max 6 bytes. 2: grab valid value by bytes section, max 3 sections.
35.5	360	* c: define the position for valid value.
2.2	361	)))
	362
35.2	363	Examples:
	364
2.2	365	* Grab bytes:
	366
35.2	367	[[image:image-20220602153621-1.png]]
2.2	368
35.2	369
2.2	370	* Grab a section.
	371
35.2	372	[[image:image-20220602153621-2.png]]
2.2	373
35.2	374
2.2	375	* Grab different sections.
	376
35.2	377	[[image:image-20220602153621-3.png]]
35.3	378
	379
35.2	380	)))
2.2	381
29.2	382	=== 3.3.4 Compose the uplink payload ===
2.2	383
29.2	384	(((
2.2	385	Through AT+COMMANDx and AT+DATACUTx we got valid value from each RS485 commands, Assume these valid value are RETURN1, RETURN2, .., to RETURNx. The next step is how to compose the LoRa Uplink Payload by these RETURNs. The command is AT+DATAUP.
35.5	386
	387
29.2	388	)))
2.2	389
29.2	390	(((
35.5	391	(% style="color:#037691" %)Examples: AT+DATAUP=0
	392
	393
29.2	394	)))
2.2	395
29.2	396	(((
	397	Compose the uplink payload with value returns in sequence and send with (% style="color:red" %)A SIGNLE UPLINK.
	398	)))
2.2	399
29.2	400	(((
2.2	401	Final Payload is
29.2	402	)))
2.2	403
29.2	404	(((
	405	(% style="color:#4f81bd" %)Battery Info+PAYVER + VALID Value from RETURN1 + Valid Value from RETURN2 + … + RETURNx
	406	)))
2.2	407
29.2	408	(((
2.2	409	Where PAYVER is defined by AT+PAYVER, below is an example screen shot.
29.2	410	)))
2.2	411
29.3	412	[[image:1653269759169-150.png\|\|height="513" width="716"]]
2.2	413
35.5	414
35.6	415	(% style="color:#037691" %)Examples: AT+DATAUP=1
2.2	416
35.5	417
30.2	418	Compose the uplink payload with value returns in sequence and send with (% style="color:red" %)Multiply UPLINKs.
2.2	419
	420	Final Payload is
	421
30.2	422	(% style="color:#4f81bd" %)Battery Info+PAYVER + PAYLOAD COUNT + PAYLOAD# + DATA
2.2	423
36.2	424	1. PAYVER: Defined by AT+PAYVER
	425	1. PAYLOAD COUNT: Total how many uplinks of this sampling.
	426	1. PAYLOAD#: Number of this uplink. (from 0,1,2,3…,to PAYLOAD COUNT)
	427	1. DATA: Valid value: max 8 bytes for each uplink so each uplink <= 11 bytes. For the last uplink, DATA will might less than 8 bytes
2.2	428
36.2	429	[[image:image-20220602155039-4.png]]
2.2	430
	431
36.2	432	So totally there will be 3 uplinks for this sampling, each uplink include 8 bytes DATA
2.2	433
36.2	434	DATA1=RETURN1 Valid Value + the first two of Valid value of RETURN10= 20 20 0a 33 90 41 02 aa
2.2	435
36.2	436	DATA2=3^^rd^^ ~~ 10^^th^^ byte of Valid value of RETURN10= 05 81 0a 20 20 20 20 2d
2.2	437
36.2	438	DATA3=the rest of Valid value of RETURN10= 30
2.2	439
36.2	440
	441	(% style="color:red" %)Notice: In firmware v1.3, the Max bytes has been changed according to the max bytes in different Frequency Bands for lowest SF. As below:
	442
	443	~* For AU915/AS923 bands, if UplinkDwell time=0, max 51 bytes for each uplink.
	444
	445	* For AU915/AS923 bands, if UplinkDwell time=0, max 11 bytes for each uplink.
	446
	447	* For US915 band, max 11 bytes for each uplink.
	448
	449	~* For all other bands: max 51 bytes for each uplink.
	450
	451
2.2	452	Below are the uplink payloads:
	453
37.2	454	[[image:1654157178836-407.png]]
2.2	455
	456
31.3	457	=== 3.3.5 Uplink on demand ===
2.2	458
37.4	459	Except uplink periodically, RS485-LN is able to uplink on demand. The server send downlink command to RS485-LN and RS485 will uplink data base on the command.
2.2	460
	461	Downlink control command:
	462
37.4	463	0x08 command: Poll an uplink with current command set in RS485-LN.
2.2	464
37.4	465	0xA8 command: Send a command to RS485-LN and uplink the output from sensors.
2.2	466
	467
	468
38.2	469	=== 3.3.6 Uplink on Interrupt ===
2.2	470
38.2	471	RS485-LN support external Interrupt uplink since hardware v1.2 release.
2.2	472
38.2	473	[[image:1654157342174-798.png]]
2.2	474
38.2	475	Connect the Interrupt pin to RS485-LN INT port and connect the GND pin to V- port. When there is a high voltage (Max 24v) on INT pin. Device will send an uplink packet.
2.2	476
	477
38.4	478	== 3.4 Uplink Payload ==
2.2	479
38.4	480	(% border="1" style="background-color:#4bacc6; color:white; width:734px" %)
	481	\|Size(bytes)\|(% style="width:120px" %)2\|(% style="width:116px" %)1\|(% style="width:386px" %)Length depends on the return from the commands
	482	\|Value\|(% style="width:120px" %)(((
2.2	483	Battery(mV)
	484
	485	&
	486
	487	Interrupt _Flag
38.4	488	)))\|(% style="width:116px" %)(((
2.2	489	PAYLOAD_VER
	490
	491
38.4	492	)))\|(% style="width:386px" %)If the valid payload is too long and exceed the maximum support payload length in server, server will show payload not provided in the LoRaWAN server.
2.2	493
	494	Below is the decoder for the first 3 bytes. The rest bytes are dynamic depends on different RS485 sensors.
	495
	496
38.4	497	== 3.5 Configure RS485-BL via AT or Downlink ==
2.2	498
38.4	499	User can configure RS485-LN via AT Commands or LoRaWAN Downlink Commands
2.2	500
38.4	501	There are two kinds of Commands:
2.2	502
38.4	503	* (% style="color:#4f81bd" %)Common Commands(%%): They should be available for each sensor, such as: change uplink interval, reset device. For firmware v1.3, user can find what common commands it supports: [[End Device AT Commands and Downlink Command>>doc:Main.End Device AT Commands and Downlink Command.WebHome]]
2.2	504
38.4	505	* (% style="color:#4f81bd" %)Sensor Related Commands(%%): These commands are special designed for RS485-LN. User can see these commands below:
2.2	506
41.7	507
	508
38.4	509	=== 3.5.1 Common Commands ===
2.2	510
38.4	511	They should be available for each of Dragino Sensors, such as: change uplink interval, reset device. For firmware v1.3, user can find what common commands it supports: [[End Device AT Commands and Downlink Command>>doc:Main.End Device AT Commands and Downlink Command.WebHome]]
2.2	512
	513
41.1	514	=== 3.5.2 Sensor related commands ===
2.2	515
41.1	516	Response feature is added to the server's downlink, a special package with a FPort of 200 will be uploaded immediately after receiving the data sent by the server.
2.2	517
41.1	518	[[image:image-20220602163333-5.png\|\|height="263" width="1160"]]
2.2	519
41.1	520	The first byte of this package represents whether the configuration is successful, 00 represents failure, 01 represents success. Except for the first byte, the other is the previous downlink. (All commands except A8 type commands are applicable)
2.2	521
	522
41.1	523	3.5.3 Sensor related commands
2.2	524
41.1	525	==== ====
2.2	526
41.1	527	==== ====

Wiki source code of RS485-LN – RS485 to LoRaWAN Converter

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