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1 (% style="text-align:center" %)
2 [[image:1653266934636-343.png||height="385" width="385"]]
3
4
5
6 **RS485-LN – RS485 to LoRaWAN Converter User Manual**
7
8
9
10
11 **Table of Contents:**
12
13 {{toc/}}
14
15
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18
19
20
21 = 1.Introduction =
22
23 == 1.1 What is RS485-LN RS485 to LoRaWAN Converter ==
24
25 (((
26 (((
27 (((
28 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.
29 )))
30 )))
31
32 (((
33 (((
34 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.
35 )))
36 )))
37
38 (((
39 (((
40 (% 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.
41 )))
42 )))
43
44 (((
45 (((
46 (% 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.
47 )))
48
49 (((
50 (% 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]]
51 )))
52 )))
53 )))
54
55 [[image:1653267211009-519.png||height="419" width="724"]]
56
57
58 == 1.2 Specifications ==
59
60
61 **Hardware System:**
62
63 * STM32L072CZT6 MCU
64 * SX1276/78 Wireless Chip 
65 * Power Consumption (exclude RS485 device):
66 ** Idle: 32mA@12v
67 ** 20dB Transmit: 65mA@12v
68
69 **Interface for Model:**
70
71 * RS485
72 * Power Input 7~~ 24V DC. 
73
74 **LoRa Spec:**
75
76 * Frequency Range:
77 ** Band 1 (HF): 862 ~~ 1020 Mhz
78 ** Band 2 (LF): 410 ~~ 528 Mhz
79 * 168 dB maximum link budget.
80 * +20 dBm - 100 mW constant RF output vs.
81 * +14 dBm high efficiency PA.
82 * Programmable bit rate up to 300 kbps.
83 * High sensitivity: down to -148 dBm.
84 * Bullet-proof front end: IIP3 = -12.5 dBm.
85 * Excellent blocking immunity.
86 * Low RX current of 10.3 mA, 200 nA register retention.
87 * Fully integrated synthesizer with a resolution of 61 Hz.
88 * FSK, GFSK, MSK, GMSK, LoRaTM and OOK modulation.
89 * Built-in bit synchronizer for clock recovery.
90 * Preamble detection.
91 * 127 dB Dynamic Range RSSI.
92 * Automatic RF Sense and CAD with ultra-fast AFC.
93 * Packet engine up to 256 bytes with CRC
94
95 == 1.3 Features ==
96
97 * LoRaWAN Class A & Class C protocol (default Class C)
98 * Frequency Bands: CN470/EU433/KR920/US915/EU868/AS923/AU915/IN865/RU864
99 * AT Commands to change parameters
100 * Remote configure parameters via LoRa Downlink
101 * Firmware upgradable via program port
102 * Support multiply RS485 devices by flexible rules
103 * Support Modbus protocol
104 * Support Interrupt uplink (Since hardware version v1.2)
105
106
107
108 == 1.4 Applications ==
109
110 * Smart Buildings & Home Automation
111 * Logistics and Supply Chain Management
112 * Smart Metering
113 * Smart Agriculture
114 * Smart Cities
115 * Smart Factory
116
117
118
119 == 1.5 Firmware Change log ==
120
121 [[RS485-LN Image files – Download link and Change log>>url:http://www.dragino.com/downloads/index.php?dir=RS485-LN/]]
122
123
124 == 1.6 Hardware Change log ==
125
126 (((
127 (((
128 v1.2: Add External Interrupt Pin.
129
130 v1.0: Release
131
132
133 )))
134 )))
135
136 = 2. Power ON Device =
137
138 (((
139 The RS485-LN can be powered by 7 ~~ 24V DC power source. Connection as below
140
141 * Power Source VIN to RS485-LN VIN+
142 * Power Source GND to RS485-LN VIN-
143
144 (((
145 Once there is power, the RS485-LN will be on.
146 )))
147
148 [[image:1653268091319-405.png]]
149
150
151 )))
152
153 = 3. Operation Mode =
154
155 == 3.1 How it works? ==
156
157 (((
158 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.
159
160
161 )))
162
163 == 3.2 Example to join LoRaWAN network ==
164
165 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. 
166
167 [[image:1653268155545-638.png||height="334" width="724"]]
168
169
170 (((
171 (((
172 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:
173 )))
174
175 (((
176 485A+ and 485B- of the sensor are connected to RS485A and RA485B of RS485-LN respectively.
177 )))
178
179 [[image:1653268227651-549.png||height="592" width="720"]]
180
181 (((
182 The LG308 is already set to connect to [[TTN V3 network >>path:https://www.thethingsnetwork.org/]]. So what we need to now is only configure the TTN V3:
183 )))
184
185 (((
186 **Step 1**: Create a device in TTN V3 with the OTAA keys from RS485-LN.
187 )))
188
189 (((
190 Each RS485-LN is shipped with a sticker with unique device EUI:
191 )))
192 )))
193
194 [[image:1652953462722-299.png]]
195
196 (((
197 (((
198 User can enter this key in their LoRaWAN Server portal. Below is TTN V3 screen shot:
199 )))
200
201 (((
202 Add APP EUI in the application.
203 )))
204 )))
205
206 [[image:image-20220519174512-1.png]]
207
208 [[image:image-20220519174512-2.png||height="323" width="720"]]
209
210 [[image:image-20220519174512-3.png||height="556" width="724"]]
211
212 [[image:image-20220519174512-4.png]]
213
214 You can also choose to create the device manually.
215
216 [[image:1652953542269-423.png||height="710" width="723"]]
217
218 Add APP KEY and DEV EUI
219
220 [[image:1652953553383-907.png||height="514" width="724"]]
221
222
223 (((
224 **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.
225 )))
226
227 [[image:1652953568895-172.png||height="232" width="724"]]
228
229
230 == 3.3 Configure Commands to read data ==
231
232 (((
233 (((
234 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>>||anchor="H3.5ConfigureRS485-BLviaATorDownlink"]] or LoRaWAN Downlink Command to configure what commands RS485-LN should send for each sampling and how to handle the return from RS485 devices.
235 )))
236
237 (((
238 (% 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
239
240
241 )))
242 )))
243
244 === 3.3.1 onfigure UART settings for RS485 or TTL communication ===
245
246 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:
247
248 (% border="1" style="background-color:#ffffcc; color:green; width:782px" %)
249 |(% style="width:128px" %)(((
250 **AT Commands**
251 )))|(% style="width:305px" %)(((
252 **Description**
253 )))|(% style="width:346px" %)(((
254 **Example**
255 )))
256 |(% style="width:128px" %)(((
257 AT+BAUDR
258 )))|(% style="width:305px" %)(((
259 Set the baud rate (for RS485 connection). Default Value is: 9600.
260 )))|(% style="width:346px" %)(((
261 (((
262 AT+BAUDR=9600
263 )))
264
265 (((
266 Options: (1200,2400,4800,14400,19200,115200)
267 )))
268 )))
269 |(% style="width:128px" %)(((
270 AT+PARITY
271 )))|(% style="width:305px" %)(((
272 Set UART parity (for RS485 connection)
273 )))|(% style="width:346px" %)(((
274 (((
275 AT+PARITY=0
276 )))
277
278 (((
279 Option: 0: no parity, 1: odd parity, 2: even parity
280 )))
281 )))
282 |(% style="width:128px" %)(((
283 AT+STOPBIT
284 )))|(% style="width:305px" %)(((
285 (((
286 Set serial stopbit (for RS485 connection)
287 )))
288
289 (((
290
291 )))
292 )))|(% style="width:346px" %)(((
293 (((
294 AT+STOPBIT=0 for 1bit
295 )))
296
297 (((
298 AT+STOPBIT=1 for 1.5 bit
299 )))
300
301 (((
302 AT+STOPBIT=2 for 2 bits
303 )))
304 )))
305
306 === 3.3.2 Configure sensors ===
307
308 (((
309 (((
310 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.
311 )))
312 )))
313
314 (% border="1" style="background-color:#ffffcc; color:green; width:806px" %)
315 |**AT Commands**|(% style="width:418px" %)**Description**|(% style="width:256px" %)**Example**
316 |AT+CFGDEV|(% style="width:418px" %)(((
317 This command is used to configure the RS485/TTL devices; they won’t be used during sampling.
318
319 AT+CFGDEV=xx xx xx xx xx xx xx xx xx xx xx xx,
320
321 mm: 0: no CRC, 1: add CRC-16/MODBUS in the end of this command
322 )))|(% style="width:256px" %)AT+CFGDEV=xx xx xx xx xx xx xx xx xx xx xx xx,m
323
324 === 3.3.3 Configure read commands for each sampling ===
325
326 (((
327 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.
328
329 To save the LoRaWAN network bandwidth, we might need to read data from different sensors and combine their valid value into a short payload.
330
331 This section describes how to achieve above goals.
332
333 During each sampling, the RS485-LN can support 15 commands to read sensors. And combine the return to one or several uplink payloads.
334
335
336 **Each RS485 commands include two parts:**
337
338 ~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.
339
340 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.
341
342 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
343
344
345 After we got the valid value from each RS485 commands, we need to combine them together with the command **AT+DATAUP**.
346
347
348 Below are examples for the how above AT Commands works.
349
350
351 **AT+COMMANDx : **This command will be sent to RS485 devices during each sampling, Max command length is 14 bytes. The grammar is:
352
353 (% border="1" style="background-color:#4bacc6; color:white; width:499px" %)
354 |(% style="width:496px" %)(((
355 **AT+COMMANDx=xx xx xx xx xx xx xx xx xx xx xx xx,m**
356
357 **xx xx xx xx xx xx xx xx xx xx xx xx: The RS485 command to be sent**
358
359 **m: 0: no CRC, 1: add CRC-16/MODBUS in the end of this command**
360 )))
361
362 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.
363
364 In the RS485-LN, we should use this command AT+COMMAND1=01 03 0B B8 00 02,1 for the same.
365
366
367 **AT+DATACUTx : **This command defines how to handle the return from AT+COMMANDx, max return length is 45 bytes.
368
369 (% border="1" style="background-color:#4bacc6; color:white; width:725px" %)
370 |(% style="width:722px" %)(((
371 **AT+DATACUTx=a,b,c**
372
373 * **a: length for the return of AT+COMMAND**
374 * **b:1: grab valid value by byte, max 6 bytes. 2: grab valid value by bytes section, max 3 sections.**
375 * **c: define the position for valid value.  **
376 )))
377
378 **Examples:**
379
380 * Grab bytes:
381
382 [[image:image-20220602153621-1.png]]
383
384
385 * Grab a section.
386
387 [[image:image-20220602153621-2.png]]
388
389
390 * Grab different sections.
391
392 [[image:image-20220602153621-3.png]]
393
394
395 )))
396
397 === 3.3.4 Compose the uplink payload ===
398
399 (((
400 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.**
401
402
403 )))
404
405 (((
406 (% style="color:#037691" %)**Examples: AT+DATAUP=0**
407
408
409 )))
410
411 (((
412 Compose the uplink payload with value returns in sequence and send with (% style="color:red" %)**A SIGNLE UPLINK**.
413 )))
414
415 (((
416 Final Payload is
417 )))
418
419 (((
420 (% style="color:#4f81bd" %)**Battery Info+PAYVER + VALID Value from RETURN1 + Valid Value from RETURN2 + … + RETURNx**
421 )))
422
423 (((
424 Where PAYVER is defined by AT+PAYVER, below is an example screen shot.
425 )))
426
427 [[image:1653269759169-150.png||height="513" width="716"]]
428
429
430 (% style="color:#037691" %)**Examples: AT+DATAUP=1**
431
432
433 Compose the uplink payload with value returns in sequence and send with (% style="color:red" %)**Multiply UPLINKs**.
434
435 Final Payload is
436
437 (% style="color:#4f81bd" %)**Battery Info+PAYVER + PAYLOAD COUNT + PAYLOAD# + DATA**
438
439
440 1. PAYVER: Defined by AT+PAYVER
441 1. PAYLOAD COUNT: Total how many uplinks of this sampling.
442 1. PAYLOAD#: Number of this uplink. (from 0,1,2,3…,to PAYLOAD COUNT)
443 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
444
445 [[image:image-20220602155039-4.png]]
446
447
448 So totally there will be 3 uplinks for this sampling, each uplink include 8 bytes DATA
449
450 DATA1=RETURN1 Valid Value + the first two of Valid value of RETURN10= **20 20 0a 33 90 41 02 aa**
451
452 DATA2=3^^rd^^ ~~ 10^^th^^ byte of Valid value of RETURN10= **05 81 0a 20 20 20 20 2d**
453
454 DATA3=the rest of Valid value of RETURN10= **30**
455
456
457 (% 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:
458
459 ~* For AU915/AS923 bands, if UplinkDwell time=0, max 51 bytes for each uplink.
460
461 * For AU915/AS923 bands, if UplinkDwell time=0, max 11 bytes for each uplink.
462
463 * For US915 band, max 11 bytes for each uplink.
464
465 ~* For all other bands: max 51 bytes for each uplink.
466
467
468 Below are the uplink payloads:
469
470 [[image:1654157178836-407.png]]
471
472
473 === 3.3.5 Uplink on demand ===
474
475 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.
476
477 Downlink control command:
478
479 **0x08 command**: Poll an uplink with current command set in RS485-LN.
480
481 **0xA8 command**: Send a command to RS485-LN and uplink the output from sensors.
482
483
484
485 === 3.3.6 Uplink on Interrupt ===
486
487 RS485-LN support external Interrupt uplink since hardware v1.2 release.
488
489 [[image:1654157342174-798.png]]
490
491 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.
492
493
494 == 3.4 Uplink Payload ==
495
496 (% border="1" style="background-color:#4bacc6; color:white; width:734px" %)
497 |**Size(bytes)**|(% style="width:120px" %)**2**|(% style="width:116px" %)**1**|(% style="width:386px" %)**Length depends on the return from the commands**
498 |Value|(% style="width:120px" %)(((
499 Battery(mV)
500
501 &
502
503 Interrupt _Flag
504 )))|(% style="width:116px" %)(((
505 PAYLOAD_VER
506
507
508 )))|(% 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.
509
510 Below is the decoder for the first 3 bytes. The rest bytes are dynamic depends on different RS485 sensors.
511
512
513 == 3.5 Configure RS485-BL via AT or Downlink ==
514
515 User can configure RS485-LN via AT Commands or LoRaWAN Downlink Commands
516
517 There are two kinds of Commands:
518
519 * (% 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: [[AT Commands and Downlink Command>>doc:Main.End Device AT Commands and Downlink Command.WebHome]]
520
521 * (% style="color:#4f81bd" %)**Sensor Related Commands**(%%): These commands are special designed for RS485-LN.  User can see these commands below:
522
523 === 3.5.1 Common Commands ===
524
525 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]]
526
527
528 === 3.5.2 Sensor related commands ===
529
530 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.
531
532 [[image:image-20220602163333-5.png||height="263" width="1160"]]
533
534 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)
535
536
537 === 3.5.3 Sensor related commands ===
538
539
540
541 ==== **RS485 Debug Command** ====
542
543 This command is used to configure the RS485 devices; they won’t be used during sampling.
544
545 * **AT Command**
546
547 (% class="box infomessage" %)
548 (((
549 **AT+CFGDEV=xx xx xx xx xx xx xx xx xx xx xx xx,m**
550 )))
551
552 m: 0: no CRC, 1: add CRC-16/MODBUS in the end of this command
553
554 * **Downlink Payload**
555
556 Format: A8 MM NN XX XX XX XX YY
557
558 Where:
559
560 * MM: 1: add CRC-16/MODBUS ; 0: no CRC
561 * NN: The length of RS485 command
562 * XX XX XX XX: RS485 command total NN bytes
563 * YY: How many bytes will be uplink from the return of this RS485 command,
564 ** if YY=0, RS485-LN will execute the downlink command without uplink;
565 ** if YY>0, RS485-LN will uplink total YY bytes from the output of this RS485 command; Fport=200
566 ** if YY=FF, RS485-LN will uplink RS485 output with the downlink command content; Fport=200.
567
568 **Example 1** ~-~-> Configure without ask for uplink (YY=0)
569
570 To connect a Modbus Alarm with below commands.
571
572 * The command to active alarm is: 0A 05 00 04 00 01 4C B0. Where 0A 05 00 04 00 01 is the Modbus command to read the register 00 40 where stored the DI status. The 4C B0 is the CRC-16/MODBUS which calculate manually.
573
574 * The command to deactivate alarm is: 0A 05 00 04 00 00 8D 70. Where 0A 05 00 04 00 00 is the Modbus command to read the register 00 40 where stored the DI status. The 8D 70 is the CRC-16/MODBUS which calculate manually.
575
576 So if user want to use downlink command to control to RS485 Alarm, he can use:
577
578 (% style="color:#4f81bd" %)**A8 01 06 0A 05 00 04 00 01 00**(%%): to activate the RS485 Alarm
579
580 (% style="color:#4f81bd" %)**A8 01 06 0A 05 00 04 00 00 00**(%%): to deactivate the RS485 Alarm
581
582 A8 is type code and 01 means add CRC-16/MODBUS at the end, the 3^^rd^^ byte is 06, means the next 6 bytes are the command to be sent to the RS485 network, the final byte 00 means this command don’t need to acquire output.
583
584
585 **Example 2** ~-~-> Configure with requesting uplink and original downlink command (**YY=FF**)
586
587 User in IoT server send a downlink command: (% style="color:#4f81bd" %)**A8 01 06 0A 08 00 04 00 01 YY**
588
589
590 RS485-LN got this downlink command and send (% style="color:#4f81bd" %)**0A 08 00 04 00 01 **(%%)to Modbus network. One of the RS485 sensor in the network send back Modbus reply **0A 08 00 04 00 00**. RS485-LN get this reply and combine with the original downlink command and uplink. The uplink message is:
591
592 **A8** (% style="color:#4f81bd" %)**0A 08 00 04 00  **(% style="color:red" %)**01 06** ** **(% style="color:green" %)**0A 08 00 04 00 00**
593
594 [[image:1654159460680-153.png]]
595
596
597
598 ==== **Set Payload version** ====
599
600 This is the first byte of the uplink payload. RS485-BL can connect to different sensors. User can set the PAYVER field to tell server how to decode the current payload.
601
602 * **AT Command:**
603
604 (% class="box infomessage" %)
605 (((
606 **AT+PAYVER: Set PAYVER field = 1**
607 )))
608
609 * **Downlink Payload:**
610
611 **0xAE 01**  ~-~-> Set PAYVER field =  0x01
612
613 **0xAE 0F**   ~-~-> Set PAYVER field =  0x0F
614
615
616
617 ==== **Set RS485 Sampling Commands** ====
618
619 AT+COMMANDx or AT+DATACUTx
620
621 These three commands are used to configure how the RS485-LN polling data from Modbus device. Detail of usage please see : [[polling RS485 device>>||anchor="H3.3.3Configurereadcommandsforeachsampling"]].
622
623
624 * **AT Command:**
625
626 (% class="box infomessage" %)
627 (((
628 **AT+COMMANDx: Configure RS485 read command to sensor.**
629 )))
630
631 (% class="box infomessage" %)
632 (((
633 **AT+DATACUTx: Configure how to handle return from RS485 devices.**
634 )))
635
636
637 * **Downlink Payload:**
638
639 **0xAF** downlink command can be used to set AT+COMMANDx or AT+DATACUTx.
640
641 (% style="color:red" %)**Note**(%%): if user use AT+COMMANDx to add a new command, he also need to send AT+DATACUTx downlink.
642
643 Format: AF MM NN LL XX XX XX XX YY
644
645 Where:
646
647 * MM: the ATCOMMAND or AT+DATACUT to be set. Value from 01 ~~ 0F,
648 * NN:  0: no CRC; 1: add CRC-16/MODBUS ; 2: set the AT+DATACUT value.
649 * LL:  The length of AT+COMMAND or AT+DATACUT command
650 * XX XX XX XX: AT+COMMAND or AT+DATACUT command
651 * YY:  If YY=0, RS485-BL will execute the downlink command without uplink; if YY=1, RS485-LN will execute an uplink after got this command.
652
653 **Example:**
654
655 (% style="color:#037691" %)**AF 03 01 06 0A 05 00 04 00 01 00**(%%): Same as AT+COMMAND3=0A 05 00 04 00 01,1
656
657 (% style="color:#037691" %)**AF 03 02 06**(% style="color:orange" %)** 10 **(% style="color:red" %)**01 **(% style="color:green" %)**05 06 09 0A**(% style="color:#037691" %)** 00**(%%): Same as AT+DATACUT3=(% style="color:orange" %)**16**(%%),(% style="color:red" %)**1**(%%),(% style="color:green" %)**5+6+9+10**
658
659 (% style="color:#037691" %)**AF 03 02 06 **(% style="color:orange" %)**0B**(% style="color:red" %)** 02 **(% style="color:green" %)**05 07 08 0A **(% style="color:#037691" %)**00**(%%): Same as AT+DATACUT3=(% style="color:orange" %)**11**(%%),(% style="color:red" %)**2**(%%),(% style="color:green" %)**5~~7+8~~10**
660
661
662
663 ==== **Fast command to handle MODBUS device** ====
664
665 AT+MBFUN is valid since v1.3 firmware version. The command is for fast configure to read Modbus devices. It is only valid for the devices which follow the [[MODBUS-RTU protocol>>url:https://www.modbustools.com/modbus.html]].
666
667 This command is valid since v1.3 firmware version
668
669 AT+MBFUN can auto read the Modbus function code: 01, 02, 03 or 04. AT+MBFUN has lower priority vs AT+DATACUT command. If AT+DATACUT command is configured, AT+MBFUN will be ignore.
670
671
672 **Example:**
673
674 * AT+MBFUN=1 and AT+DATACUT1/AT+DATACUT2 are not configure (0,0,0). So RS485-LN.
675 * AT+COMMAND1= 01 03 00 10 00 08,1 ~-~-> read slave address 01 , function code 03, start address 00 01, quantity of registers 00 08.
676 * AT+COMMAND2= 01 02 00 40 00 10,1 ~-~-> read slave address 01 , function code 02, start address 00 40, quantity of inputs 00 10.
677
678 [[image:image-20220602165351-6.png]]
679
680 [[image:image-20220602165351-7.png]]
681
682
683
684 ==== **RS485 command timeout** ====
685
686 Some Modbus device has slow action to send replies. This command is used to configure the RS485-LN to use longer time to wait for their action.
687
688 Default value: 0, range:  0 ~~ 65 seconds
689
690 * **AT Command:**
691
692 (% class="box infomessage" %)
693 (((
694 **AT+CMDDLaa=hex(bb cc)*1000**
695 )))
696
697 **Example:**
698
699 **AT+CMDDL1=1000** to send the open time to 1000ms
700
701
702 * **Downlink Payload:**
703
704 **0x AA aa bb cc**
705
706 Same as: AT+CMDDLaa=hex(bb cc)*1000
707
708 **Example:**
709
710 0xAA 01 00 01  ~-~-> Same as **AT+CMDDL1=1000 ms**
711
712
713
714 ==== **Uplink payload mode** ====
715
716 Define to use one uplink or multiple uplinks for the sampling.
717
718 The use of this command please see: [[Compose Uplink payload>>||anchor="H3.3.4Composetheuplinkpayload"]]
719
720 * **AT Command:**
721
722 (% class="box infomessage" %)
723 (((
724 **AT+DATAUP=0**
725 )))
726
727 (% class="box infomessage" %)
728 (((
729 **AT+DATAUP=1**
730 )))
731
732
733 * **Downlink Payload:**
734
735 **0xAD 00**  **~-~->** Same as AT+DATAUP=0
736
737 **0xAD 01**  **~-~->** Same as AT+DATAUP=1
738
739
740
741 ==== **Manually trigger an Uplink** ====
742
743 Ask device to send an uplink immediately.
744
745 * **AT Command:**
746
747 No AT Command for this, user can press the [[ACT button>>||anchor="H3.7Buttons"]] for 1 second for the same.
748
749
750 * **Downlink Payload:**
751
752 **0x08 FF**, RS485-LN will immediately send an uplink.
753
754
755
756 ==== **Clear RS485 Command** ====
757
758 The AT+COMMANDx and AT+DATACUTx settings are stored in special location, user can use below command to clear them.
759
760 * **AT Command:**
761
762 **AT+CMDEAR=mm,nn**   mm: start position of erase ,nn: stop position of erase
763
764 Etc. AT+CMDEAR=1,10 means erase AT+COMMAND1/AT+DATACUT1 to AT+COMMAND10/AT+DATACUT10
765
766 Example screen shot after clear all RS485 commands. 
767
768
769 The uplink screen shot is:
770
771 [[image:1654160691922-496.png]]
772
773
774 * **Downlink Payload:**
775
776 **0x09 aa bb** same as AT+CMDEAR=aa,bb
777
778
779
780 ==== **Set Serial Communication Parameters** ====
781
782 Set the Rs485 serial communication parameters:
783
784 * **AT Command:**
785
786 Set Baud Rate:
787
788 (% class="box infomessage" %)
789 (((
790 **AT+BAUDR=9600**    ~/~/ Options: (1200,2400,4800,14400,19200,115200)
791 )))
792
793 Set UART Parity
794
795 (% class="box infomessage" %)
796 (((
797 **AT+PARITY=0**    ~/~/ Option: 0: no parity, 1: odd parity, 2: even parity
798 )))
799
800 Set STOPBIT
801
802 (% class="box infomessage" %)
803 (((
804 **AT+STOPBIT=0**    ~/~/ Option: 0 for 1bit; 1 for 1.5 bit ; 2 for 2 bits
805 )))
806
807
808 * **Downlink Payload:**
809
810 **A7 01 aa bb**: Same  AT+BAUDR=hex(aa bb)*100
811
812 **Example:**
813
814 * A7 01 00 60   same as AT+BAUDR=9600
815 * A7 01 04 80  same as AT+BAUDR=115200
816
817 A7 02 aa: Same as  AT+PARITY=aa  (aa value: 00 , 01 or 02)
818
819 A7 03 aa: Same as  AT+STOPBIT=aa  (aa value: 00 , 01 or 02)
820
821
822 == 3.6 Listening mode for RS485 network ==
823
824 This feature support since firmware v1.4
825
826 RS485-LN supports listening mode, it can listen the RS485 network packets and send them via LoRaWAN uplink. Below is the structure. The blue arrow shows the RS485 network packets to RS485-LN.
827
828 [[image:image-20220602171200-8.png||height="567" width="1007"]]
829
830 To enable the listening mode, use can run the command AT+RXMODE.
831
832
833 (% border="1" style="background-color:#ffffcc; width:500px" %)
834 |=(% style="width: 161px;" %)**Command example:**|=(% style="width: 337px;" %)**Function**
835 |(% style="width:161px" %)AT+RXMODE=1,10 |(% style="width:337px" %)Enable listening mode 1, if RS485-LN has received more than 10 RS485 commands from the network. RS485-LN will send these commands via LoRaWAN uplinks.
836 |(% style="width:161px" %)AT+RXMODE=2,500|(% style="width:337px" %)Enable listening mode 2, RS485-LN will capture and send a 500ms content once from the first detect of character. Max value is 65535 ms
837 |(% style="width:161px" %)AT+RXMODE=0,0|(% style="width:337px" %)Disable listening mode. This is the default settings.
838 |(% style="width:161px" %) |(% style="width:337px" %)A6 aa bb cc  same as AT+RXMODE=aa,(bb<<8 ~| cc)
839
840 **Downlink Command:**
841
842 **0xA6 aa bb cc ** same as AT+RXMODE=aa,(bb<<8 | cc)
843
844
845 **Example**:
846
847 The RS485-LN is set to AT+RXMODE=2,1000
848
849 There is a two Modbus commands in the RS485 network as below:
850
851 The Modbus master send a command: (% style="background-color:#ffc000" %)01 03 00 00 00 02 c4 0b
852
853 And Modbus slave reply with: (% style="background-color:green" %)01 03 04 00 00 00 00 fa 33
854
855 RS485-LN will capture both and send the uplink: (% style="background-color:#ffc000" %)01 03 00 00 00 02 c4 0b  (% style="background-color:green" %)01 03 04 00 00 00 00 fa 33
856
857 [[image:image-20220602171200-9.png]]
858
859
860 (% style="color:red" %)Notice: Listening mode can work with the default polling mode of RS485-LN. When RS485-LN is in to send the RS485 commands (from AT+COMMANDx), the listening mode will be interrupt for a while.
861
862
863 == 3.7 Buttons ==
864
865
866 (% border="1" style="background-color:#f7faff; width:500px" %)
867 |=**Button**|=(% style="width: 1420px;" %)**Feature**
868 |**ACT**|(% style="width:1420px" %)If RS485 joined in network, press this button for more than 1 second, RS485 will upload a packet, and the SYS LED will give a (% style="color:blue" %)**Blue blink**
869 |**RST**|(% style="width:1420px" %)Reboot RS485
870 |**PRO**|(% style="width:1420px" %)Use for upload image, see [[How to Update Image>>||anchor="H6.1Howtoupgradetheimage3F"]]
871
872
873 == 3.8 LEDs ==
874
875 (% border="1" style="background-color:#f7faff; width:500px" %)
876 |=**LEDs**|=**Feature**
877 |**PWR**|Always on if there is power
878 |**SYS**|After device is powered on, the SYS will (% style="color:green" %)**fast blink in GREEN** (%%)for 5 times, means RS485-LN start to join LoRaWAN network. If join success, SYS will be (% style="color:green" %)**on GREEN for 5 seconds**(%%)**. **SYS will (% style="color:green" %)**blink Blue**(%%) on every upload and (% style="color:green" %)**blink Green**(%%) once receive a downlink message.
879
880
881 = 4. Case Study =
882
883 User can check this URL for some case studies: [[APP RS485 COMMUNICATE WITH SENSORS>>doc:Main.Application Note \: Communicate with Different Sensors ----- RS485-LN RS485-BL.WebHome]]
884
885
886 = 5. Use AT Command =
887
888 == 5.1 Access AT Command ==
889
890 RS485-BL supports AT Command set. User can use a USB to TTL adapter plus the 3.5mm Program Cable to connect to RS485-BL to use AT command, as below.
891
892 [[image:1654162355560-817.png]]
893
894
895 In PC, User needs to set (% style="color:blue" %)**serial tool**(%%)(such as [[putty>>url:https://www.chiark.greenend.org.uk/~~sgtatham/putty/latest.html]], SecureCRT) baud rate to (% style="color:green" %)**9600**(%%) to access to access serial console of RS485-BL. The default password is 123456. Below is the output for reference:
896
897 [[image:1654162368066-342.png]]
898
899
900 More detail AT Command manual can be found at [[AT Command Manual>>https://www.dragino.com/downloads/index.php?dir=LT_LoRa_IO_Controller/LT33222-L/]]
901
902
903 == 5.2 Common AT Command Sequence ==
904
905 === 5.2.1 Multi-channel ABP mode (Use with SX1301/LG308) ===
906
907 If device has not joined network yet:
908
909 (% class="box infomessage" %)
910 (((
911 **AT+FDR**
912 )))
913
914 (% class="box infomessage" %)
915 (((
916 **AT+NJM=0**
917 )))
918
919 (% class="box infomessage" %)
920 (((
921 **ATZ**
922 )))
923
924
925 If device already joined network:
926
927 (% class="box infomessage" %)
928 (((
929 **AT+NJM=0**
930 )))
931
932 (% class="box infomessage" %)
933 (((
934 **ATZ**
935 )))
936
937
938 === 5.5.2 Single-channel ABP mode (Use with LG01/LG02) ===
939
940
941 (% style="background-color:#dcdcdc" %)**AT+FDR** (%%) Reset Parameters to Factory Default, Keys Reserve
942
943 (% style="background-color:#dcdcdc" %)**AT+NJM=0 **(%%)Set to ABP mode
944
945 (% style="background-color:#dcdcdc" %)**AT+ADR=0** (%%)Set the Adaptive Data Rate Off
946
947 (% style="background-color:#dcdcdc" %)**AT+DR=5**   (%%)Set Data Rate
948
949 (% style="background-color:#dcdcdc" %)**AT+TDC=60000** (%%) Set transmit interval to 60 seconds
950
951 (% style="background-color:#dcdcdc" %)**AT+CHS=868400000**(%%) Set transmit frequency to 868.4Mhz
952
953 (% style="background-color:#dcdcdc" %)**AT+RX2FQ=868400000** (%%) Set RX2Frequency to 868.4Mhz (according to the result from server)
954
955 (% style="background-color:#dcdcdc" %)**AT+RX2DR=5**  (%%) Set RX2DR to match the downlink DR from server. see below
956
957 (% style="background-color:#dcdcdc" %)**AT+DADDR=26** (%%) 01 1A F1 Set Device Address to 26 01 1A F1, this ID can be found in the LoRa Server portal.
958
959 (% style="background-color:#dcdcdc" %)**ATZ**       (%%) Reset MCU
960
961
962 (% style="color:red" %)**Note:**
963
964 (% style="color:red" %)1. Make sure the device is set to ABP mode in the IoT Server.
965 2. Make sure the LG01/02 gateway RX frequency is exactly the same as AT+CHS setting.
966 3. Make sure SF / bandwidth setting in LG01/LG02 match the settings of AT+DR. refer [[this link>>url:http://www.dragino.com/downloads/index.php?dir=LoRa_Gateway/&file=LoRaWAN%201.0.3%20Regional%20Parameters.xlsx]] to see what DR means.
967 4. The command AT+RX2FQ and AT+RX2DR is to let downlink work. to set the correct parameters, user can check the actually downlink parameters to be used. As below. Which shows the RX2FQ should use 868400000 and RX2DR should be 5
968
969 [[image:1654162478620-421.png]]
970
971
972 = 6. FAQ =
973
974 == 6.1 How to upgrade the image? ==
975
976 The RS485-LN LoRaWAN Controller is shipped with a 3.5mm cable, the cable is used to upload image to RS485-LN to:
977
978 * Support new features
979 * For bug fix
980 * Change LoRaWAN bands.
981
982 Below shows the hardware connection for how to upload an image to RS485-LN:
983
984 [[image:1654162535040-878.png]]
985
986 **Step1:** Download [[flash loader>>url:https://www.st.com/content/st_com/en/products/development-tools/software-development-tools/stm32-software-development-tools/stm32-programmers/flasher-stm32.html]].
987
988 **Step2**: Download the [[LT Image files>>url:http://www.dragino.com/downloads/index.php?dir=LT_LoRa_IO_Controller/LT33222-L/image/]].
989
990 **Step3: **Open flashloader; choose the correct COM port to update.
991
992 (((
993 (% style="color:blue" %) Hold down the PRO button and then momentarily press the RST reset button and the SYS led will change from OFF to ON, While SYS LED is RED ON, it means the RS485-LN is ready to be program.
994 )))
995
996
997 [[image:image-20220602175818-12.png]]
998
999
1000 [[image:image-20220602175848-13.png]]
1001
1002
1003 [[image:image-20220602175912-14.png]]
1004
1005
1006 **Notice**: In case user has lost the program cable. User can hand made one from a 3.5mm cable. The pin mapping is:
1007
1008 [[image:image-20220602175638-10.png]]
1009
1010
1011 == 6.2 How to change the LoRa Frequency Bands/Region? ==
1012
1013 User can follow the introduction for [[how to upgrade image>>||anchor="H6.1Howtoupgradetheimage3F"]]. When download the images, choose the required image file for download.
1014
1015
1016 == 6.3 How many RS485-Slave can RS485-BL connects? ==
1017
1018 The RS485-BL can support max 32 RS485 devices. Each uplink command of RS485-BL can support max 16 different RS485 command. So RS485-BL can support max 16 RS485 devices pre-program in the device for uplink. For other devices no pre-program, user can use the [[downlink message (type code 0xA8) to poll their info>>||anchor="H3.3.3Configurereadcommandsforeachsampling"]].
1019
1020
1021 == 6.4 Compatible question to ChirpStack and TTI LoRaWAN server ? ==
1022
1023 When user need to use with ChirpStack or TTI. Please set AT+RPL=4.
1024
1025 Detail info check this link: [[Set Packet Receiving Response Level>>doc:Main.End Device AT Commands and Downlink Command.WebHome||anchor="H7.23SetPacketReceivingResponseLevel"]]
1026
1027
1028 = 7. Trouble Shooting =
1029
1030 == 7.1 Downlink doesn’t work, how to solve it? ==
1031
1032 Please see this link for debug: [[LoRaWAN Communication Debug>>doc:Main.LoRaWAN Communication Debug.WebHome]]
1033
1034
1035 == 7.2 Why I can’t join TTN V3 in US915 /AU915 bands? ==
1036
1037 It might about the channels mapping. Please see for detail: [[Notice of Frequency band>>doc:Main.LoRaWAN Communication Debug.WebHome||anchor="H2.NoticeofUS9152FCN4702FAU915Frequencyband"]]
1038
1039
1040 = 8. Order Info =
1041
1042 (% style="color:blue" %)**Part Number: RS485-LN-XXX**
1043
1044 (% style="color:blue" %)**XXX:**
1045
1046 * (% style="color:blue" %)**EU433**(%%): frequency bands EU433
1047 * (% style="color:blue" %)**EU868**(%%): frequency bands EU868
1048 * (% style="color:blue" %)**KR920**(%%): frequency bands KR920
1049 * (% style="color:blue" %)**CN470**(%%): frequency bands CN470
1050 * (% style="color:blue" %)**AS923**(%%): frequency bands AS923
1051 * (% style="color:blue" %)**AU915**(%%): frequency bands AU915
1052 * (% style="color:blue" %)**US915**(%%): frequency bands US915
1053 * (% style="color:blue" %)**IN865**(%%): frequency bands IN865
1054 * (% style="color:blue" %)**RU864**(%%): frequency bands RU864
1055 * (% style="color:blue" %)**KZ865**(%%): frequency bands KZ865
1056
1057
1058
1059 = 9.Packing Info =
1060
1061
1062 **Package Includes**:
1063
1064 * RS485-LN x 1
1065 * Stick Antenna for LoRa RF part x 1
1066 * Program cable x 1
1067
1068 **Dimension and weight**:
1069
1070 * Device Size: 13.5 x 7 x 3 cm
1071 * Device Weight: 105g
1072 * Package Size / pcs : 14.5 x 8 x 5 cm
1073 * Weight / pcs : 170g
1074
1075
1076
1077 = 10. FCC Caution for RS485LN-US915 =
1078
1079 (((
1080 Any Changes or modifications not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment.
1081 )))
1082
1083 (((
1084 This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.
1085 )))
1086
1087 (((
1088
1089 )))
1090
1091 (((
1092 **IMPORTANT NOTE:**
1093 )))
1094
1095 (((
1096 **Note: **This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:
1097 )))
1098
1099 (((
1100 —Reorient or relocate the receiving antenna.
1101 )))
1102
1103 (((
1104 —Increase the separation between the equipment and receiver.
1105 )))
1106
1107 (((
1108 —Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
1109 )))
1110
1111 (((
1112 —Consult the dealer or an experienced radio/TV technician for help.
1113 )))
1114
1115 (((
1116
1117 )))
1118
1119 (((
1120 **FCC Radiation Exposure Statement:**
1121 )))
1122
1123 (((
1124 This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment.This equipment should be installed and operated with minimum distance 20cm between the radiator& your body.
1125 )))
1126
1127
1128 = 11. Support =
1129
1130 * (((
1131 Support is provided Monday to Friday, from 09:00 to 18:00 GMT+8. Due to different timezones we cannot offer live support. However, your questions will be answered as soon as possible in the before-mentioned schedule.
1132 )))
1133 * (((
1134 Provide as much information as possible regarding your enquiry (product models, accurately describe your problem and steps to replicate it etc) and send a mail to [[support@dragino.com>>url:file:///D:/市场资料/说明书/LoRa/LT系列/support@dragino.com]].
1135 )))