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Wiki source code of LoRaWAN Communication Debug

Version 39.2 by Xiaoling on 2023/03/23 17:08
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1 **~ Table of Contents:**
2
3 {{toc/}}
4
5
6
7 = 1.(% style="display:none" %) (%%) OTAA Join Process Debug =
8
9
10 These pages are useful to check what is wrong on the Join process. Below shows the four steps that we can check the Join Process.
11 \\**If user has checked below steps and still can't solve the problem, please send us (support @ dragino.com) the sceenshots for each step to check. They include:**
12
13 * End node console to show the Join freuqency and DR. (If possible)
14
15 * Gateway (from gateway UI) traffic to show the packet got from end node and receive from Server. (If possible)
16
17 * Gateway traffic (from server UI) to shows the data exchange between gateway and server. (Normaly possible)
18
19 * End Node traffic (from server UI) to shows end node activity in server. (Normaly possible)
20
21 * End Node Keys screen shot shows in end node and server. so we can check if the keys are correct. (In most case, we found keys doesn't match, especially APP EUI)
22
23 (% style="color:blue" %)**1. End Device Join Screen shot, we can check:**
24
25 * If the device is sending join request to server?
26
27 * What frequency the device is sending?
28
29 [[image:image-20220526164956-15.png||height="591" width="1153"]]
30
31 Console Output from End device to see the transmit frequency
32
33
34
35 (% style="color:blue" %)**2. Gateway packet traffic in gateway web or ssh. we can check:**
36
37 * If the gateway receive the Join request packet from sensor? (If this fail, check if the gateway and sensor works on the match frequency)
38
39 * If the gateway gets the Join Accept message from server and transmit it via LoRa?
40
41 [[image:image-20220526163608-2.png]]
42
43 Console Output from Gateway to see packets between end node and server.
44
45
46
47 (% style="color:blue" %)**3. Gateway Traffic Page in LoRaWAN Server**
48
49 * If the Join Request packet arrive the gateway traffic in server? If not, check the internet connection and gateway LoRaWAN server settings.
50
51 * If the server send back a Join Accept for the Join Request? if not, check if the keys from the device match the keys you put in the server, or try to choose a different server route for this end device.
52
53 * If the Join Accept message are in correct frequency? If you set the server to use US915 band, and your end node and gateway is EU868, you will see the Join Accept message are in US915 band so no possible to Join success.
54
55 [[image:image-20220526163633-3.png]]
56
57 The Traffic for the End node in the server, use TTN as example
58
59
60
61 (% style="color:blue" %)**4. Data Page in LoRaWAN server**
62
63 * If this data page shows the Join Request message from the end node? If not, most properly you have wrong settings in the keys. Keys in the server doesn't match the keys in End Node.
64
65 [[image:image-20220526163704-4.png]]
66
67 The data for the end device set in server
68
69
70 [[image:image-20220526163732-5.png]]
71
72 Check if OTAA Keys match the keys in device
73
74
75 = 2. Notice of US915/CN470/AU915 Frequency band =
76
77
78 (((
79 If user has problem to work with lorawan server in band US915/AU915/CN470, he can check:
80 )))
81
82 * (((
83 What **sub-band** the server support ?
84 )))
85 * (((
86 What is the **sub-band** the gateway support ?
87 )))
88 * (((
89 What is the **sub-band** the end node is using ?
90 )))
91
92 (((
93 All of above should match so End Node can properly Join the server and don't have packet lost.
94 )))
95
96 (((
97
98 )))
99
100 (((
101 In LoRaWAN protocol, the frequency bands US915, AU915, CN470 each includes at least 72 frequencies. Many gateways support only 8 or 16 frequencies, and server might support 8 frequency only. In this case, the OTAA join time and uplink schedule is long and unpredictable while the end node is hopping in 72 frequencies, because the end node will send data in many frequency that the gateway or server doesn,t support.
102 )))
103
104 (((
105
106 )))
107
108 (((
109 Here are the freuqency tables for these bands as reference:
110 )))
111
112 [[image:image-20220526163801-6.png]]
113
114 US915 Channels
115
116
117 [[image:image-20220526163926-7.png]]
118
119 AU915 Channels
120
121
122 [[image:image-20220526163941-8.png]]
123
124 (((
125 CN470 Channels
126
127
128 )))
129
130 (((
131 If we look at the [[TTN network server frequency plan>>url:https://www.thethingsnetwork.org/docs/lorawan/frequency-plans.html]], we can see the US915 frequency band use the channel 8~~15.So the End Node must work at the same frequency in US915 8~~15 channels for TTN server.
132 )))
133
134 [[image:image-20220526164052-9.png]]
135
136 (((
137 TTN FREQUENCY PLAN
138
139 (% style="display:none" %) (%%)
140 )))
141
142 (((
143 In dragino end node, user can use AT+CHE command to set what frequencies set the end node will use. The default settings for Dragino end node are preconfigure for TTN server, so use 8~~15 channels, which is **AT+CHE=2**. (AT+CHE=1 for first 8 channels, AT+CHE=2 for second 8 channels.. etc, and AT+CHE=0 for all 72 channels. )
144 )))
145
146 (% style="display:none" %) (%%)
147
148 = 3. Why i see data lost/unperiocially uplink data? Even the signal strength is good =
149
150
151 In this case, we can check if the frequency band matches in End Node, Gateway and LoRaWAN server. A typical case is using US915 in ChirpStack server as below:
152
153 * (% style="color:blue" %)**End node** (%%) ~-~-> Use Sub-band2 (Channel 8,9,10,11,12,13,14,15) for Dragino Sensor. ADR is also enable, this is the default settings for dragino sensors.
154
155 * (% style="color:blue" %)**Gateway** (%%) ~-~-> Use Sub-band2 (Channel 8,9,10,11,12,13,14,15) for Dragino Gateway. this is the default settings for dragino sensors.
156
157 * (% style="color:blue" %)**LoRaWAN server**  (%%) ~-~-> ChirpStack default installation and use Sub-band1, **enabled_uplink_channels=[0, 1, 2, 3, 4, 5, 6, 7]** in the file chirpstack-network-server.toml.
158
159 (((
160 When Sensor power on, it will use sub-band2 to join the network, the frequency matches the settings in gateway so all Join Request will be passed to the server for Join. Server will ask the sensor to change to Sub-band1 in the Join Accept downlink message. Sensor will change to sub-band1 for data upload. This cause the sensor and gateway have different frequencies so user see lost of most data or even no data.
161 )))
162
163
164 (((
165 Use Subband2 as a default subband cause the sensor to have problem to work with the LoRaWAN server which use other subband, and use need to access to the end node to change the subband by console. that is not user frendily,. So since Dragino LoRaWAN Stack version DLS-005(release on end of 2020), we have changed the device to use All Subbands for OTAA join, for example, device will use the first frequency in Sub-Band1 as firt OTAA join packet, then use the first frequency in Sub-Band 2 , then first frequency in sub-band 3, and so on. LoRaWAN server will normally provide the required subband in the OTAA accept process, so end node will know what subband it use after join. If LoRaWAN server doesn't provide subband info in OTAA join, end node will use the subband which join success as the working subband. So the new method cause a longer OTAA Join time but will be compatible with all LoRaWAN server. And new method won't affect the normal uplink after Join Success.
166 )))
167
168
169 = 4. Transmision on ABP Mode =
170
171
172 (((
173 In ABP mode, there is a Frame Counter Checks. With this check enabled, the server will only accept the frame with a higher counter. If you reboot the device in ABP mode, the device will start from count 0, so you won't be able to see the frame update in server.
174 )))
175
176 (((
177 So in ABP mode, first check if the packet already arrive your gateway, if the packet arrive gatewat but didn't arrive server. Please check if this is the issue.
178 )))
179
180 (((
181 To solve this, disable the Frame Counter Check will solve this issue , or reset the frame counter in the device page.
182 )))
183
184 [[image:image-20220526164508-10.png]]
185
186 Disable Frame Counter Check in ABP Mode
187
188
189 = 5. Downstream Debug =
190
191 == 5.1 How it work ==
192
193
194 LoRaWAN End node will open two receive windows to receive the downstream data. If the downstream packets arrive the end node at these receive windows, the end node will be able to get this packet and process it.
195
196 (((
197 Depends on Class A or Class C, the receive windows will be a little difference,
198 )))
199
200 [[image:image-20220531161828-1.png]]
201
202 receive windows for Class A and Class C
203
204
205 Below are the requirement for the End Device to receive the packets.
206
207 * The End Device must open the receive windows: RX1 or RX2
208
209 * The LoRaWAN server must send a downstream packet, and the gateway forward this downstream packet for this end node.
210
211 * This downstream packet must arrive to the end node while RX1 or RX2 is open.
212
213 * This packet must match the frequency of the RX1 or RX2 window.
214
215 * This packet must match the DataRate of RX1(RX1DR) or RX2 (RX2DR). (% style="color:red" %)**This is the common fail point, because different lorawan server might use different RX2DR and they don't info End Node via ADR message so cause the mismatch. If this happen, user need to change the RX2DR to the right value in end node. In OTAA, LoRaWAN Server will send the RX2DR setting in Join Accept message so the end node will auto adjust. but ABP uplink doesn't support this auto change.**
216
217
218
219 == 5.2 See Debug Info ==
220
221
222 (((
223 (% style="color:blue" %)**For LoRaWAN Server**
224 )))
225
226 (((
227 We can check if there is downlink message for this end node, use TTN for example:
228 )))
229
230 (((
231 Configure a downstream to the end device
232 )))
233
234 [[image:image-20220526164623-12.png]]
235
236 (((
237 Set a downstream in TTN and see it is sent
238 )))
239
240
241 (((
242 This downstream info will then pass to the gateway downstream list. and include the DR which is used (SF9BW125) in EU868 is DR3
243 )))
244
245 [[image:image-20220526164650-13.png]]
246
247 (((
248 Gateway Traffic can see this downstream info
249 )))
250
251
252
253 (((
254 (% style="color:blue" %)**For LoRaWAN Gateway**
255 )))
256
257 (((
258 When the downstream packet appear on the traffic of Gateway page. The LoRaWAN gateway can get it from LoRaWAN server and transmit it. In Dragion Gateway, this can be checked by runinng "logread -f" in the SSH console. and see below:
259 )))
260
261 [[image:image-20220526164734-14.png]]
262
263 (((
264 Gateway Sent out this packet
265 )))
266
267
268
269 (((
270 (% style="color:blue" %)**For End Node**
271 )))
272
273 (((
274 we can use AT Command (AT+CFG) to check the RX1 configure and RX2 configure. as below:
275 )))
276
277 (((
278 * (% style="color:#037691" %)**AT+RX2FQ=869525000**  (%%) **~-~-->**  The RX2 Window frequency
279
280 * (% style="color:#037691" %)**AT+RX2DR=3**          (%%) **~-~-->**  The RX2 DataRate
281
282 * (% style="color:#037691" %)**AT+RX1DL=1000**       (%%) ** ~-~-->**  Receive Delay 1
283
284 * (% style="color:#037691" %)**AT+RX2DL=2000**       (%%) **~-~--> ** Receive Delay 2
285 )))
286
287 (((
288 (% style="color:blue" %)**when the device running, we can see below info:**
289 )))
290
291 {{{ [12502]***** UpLinkCounter= 0 *****
292 [12503]TX on freq 868500000 Hz at DR 0
293 [13992]txDone
294 [15022]RX on freq 868500000 Hz at DR 0 --> RX1 window open at frequency: 868500000, DR0, after 15022-13992= 1030ms of txdone
295 [15222]rxTimeOut --> no packet arrive in RX1 window. (duration: 200ms)
296 [15987]RX on freq 869525000 Hz at DR 3 --> RX2 window open at frequency: 869525000, DR3, after 15987-13992= 1995ms of txdone
297 [16027]rxTimeOut --> no packet arrive in RX2 window. (duration: 40 ms)}}}
298
299 (((
300
301
302
303 )))
304
305 (((
306 (% style="color:blue" %)**Another message:**
307 )))
308
309 {{{ [12502]***** UpLinkCounter= 0 *****
310 [12503]TX on freq 868100000 Hz at DR 0
311 [13992]txDone
312 [15022]RX on freq 868100000 Hz at DR 0
313 [15222]rxTimeOut
314 [15987]RX on freq 869525000 Hz at DR 3
315 [16185]rxDone --> We have got the downstream packet.
316 Rssi= -64
317 Receive data
318 1:0012345678}}}
319
320
321 == 5.3 If problem doesn't solve ==
322
323
324 (% style="color:red" %)**If user has checked below steps and still can't solve the problem, please send us (support @ dragino.com) the sceenshots for each step to check. They include:**
325
326 * End node console to show the transmit freuqency and DR.
327
328 * Gateway (from gateway UI) traffic to show the packet got from end node and receive from Server.
329
330 * Gateway traffic (from server UI) to shows the data exchange between gateway and server.
331
332 * End Node traffic (from server UI) to shows end node activity in server.
333
334
335
336 = 6. Downlink Issue ~-~- Packet REJECTED, unsupported frequency =
337
338
339 (((
340 In LoRaWAN, the gatewat will use the frequency specify by the server to transmit a packet as downlink purpose. Each Frequency band has different downlink frequency. and the gateway has a frequency range limited to transmit downlink.
341 )))
342
343 (((
344
345 )))
346
347 (((
348 So if the LoRaWAN server is an AS923 server which ask the gateway to transmit at 923.2Mhz frequency, but the gateway is IN868 frequency band (support 865~~867Mhz to transmit). In the gateway log it will show something like below:
349 )))
350
351 {{{Sat Nov 21 08:04:17 2020 daemon.info lora_pkt_fwd[1680]: ERROR~ Packet REJECTED, unsupported frequency - 923200000 (min:865000000,max:867000000)}}}
352
353 (((
354
355 )))
356
357 (((
358 In this case, please double check the gateway frequency and the server frequency band.
359 )))
360
361
362 = 7. Decrypt a LoRaWAN Packet =
363
364
365 (% style="color:blue" %)**1. LHT65 End device configure:**
366
367 **Change to ABP Mode:  AT+NJM=0**
368
369 **Change to fix frequency:  AT+CHS=904900000**
370
371 **Change to fix DR:  AT+DR=0**
372
373
374 [[image:image-20220526165525-16.png]]
375
376
377
378 (% style="color:blue" %)**2. In LG02 , configure to receive above message**
379
380 [[image:image-20220526165612-17.png]]
381
382
383 In LG02 console, we can see the hex receive are:
384
385 [[image:image-20220526171112-21.png]]
386
387
388
389 (% style="color:blue" %)**3. Decode the info in web**
390
391 [[https:~~/~~/lorawan-packet-decoder-0ta6puiniaut.runkit.sh>>url:https://lorawan-packet-decoder-0ta6puiniaut.runkit.sh/]]
392
393 Need these three fields:
394
395 LoRa packet hex format: 40c1190126800100024926272bf18bbb6341584e27e23245 (from LG02)
396
397 AT+NWKSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 11 (End node Network Session Key)
398
399 AT+APPSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 11 (End Node App Session Key)
400
401
402 [[https:~~/~~/lorawan-packet-decoder-0ta6puiniaut.runkit.sh/?data=40c1190126800100024926272bf18bbb6341584e27e23245&nwkskey=00000000000000000000000000000111&appskey=00000000000000000000000000000111>>url:https://lorawan-packet-decoder-0ta6puiniaut.runkit.sh/?data=40c1190126800100024926272bf18bbb6341584e27e23245&nwkskey=00000000000000000000000000000111&appskey=00000000000000000000000000000111]]
403
404 [[image:image-20220526171029-20.png]]
405
406 (((
407 The FRMPayload is the device payload.
408 )))
409
410
411 = 8. Why i see uplink 0x00 periodcally on the LHT65 v1.8 firmware =
412
413
414 Since firmware v1.8, LHT65 will send MAC command to request time, in the case if DR only support max 11 bytes, this MAC command will be bundled to a separate uplink payload with 0x00.
415
416
417 = 9. Why do I see a "MIC Mismatch" error message from the server? =
418
419
420 (((
421 1)  If the user receives a "MIC Mismatch" message after registering the node on the server.
422 )))
423
424 (((
425 It is likely that the user filled in the wrong APPKEY when registering the node. Many users fill in "APPSKEY".
426 )))
427
428 * (((
429 Please note the distinction between "APPKEY" and "APPSKEY".
430 )))
431
432 (((
433 2）If the node works on the server for a period of time, the device stops working and receives a "MIC Mismatch" message.
434 )))
435
436 (((
437 The user needs a USB-TTL adapter to connect the serial port to modify the node APPKEY.
438 )))
439
440 * (((
441 If a node is registered with multiple servers, it may also cause the "mic mismatch" error.
442 )))
443
444 (% class="wikigeneratedid" %)
445 3）Wrong Regional Parameters version selected
446 We generally use versions above 1.0.2
447
448 (% class="wikigeneratedid" %)
449 [[image:image-20230322163227-1.png]]
450
451 (% class="wikigeneratedid" %)
452 4）We have had cases where it was automatically fixed the next day despite no manual changes, probably a server side issue
453
454
455 = 10. Why i got the payload only with "0x00" or "AA~=~="? =
456
457
458 (% style="color:blue" %)**Why this happen:**
459
460 For US915, AU915 or AS923 frequencies.It is possible because: .
461
462 When using the frequency mentioned above, the server sometimes adjusts the Data Rate (DR) of the node, because the end node has Adaptive Data Rate (ADR) Enabled.
463
464 When the server adjusts end node data rate to 0, the maximum payload length is 11 bytes. The server sometimes sends an ADR packet to the end node, and the node will reply to the server after receiving the ADR packet, but the number of payload bytes exceeds the limit, so it will send a normal uplink packet, and following an additional 00 data packet to handle this MAC command response.
465
466
467 (% style="color:blue" %)**How to solve:**
468
469 Solution: Use the decoder to filter out this 0x00 packet.
470
471 Some node decoders may not have the filter function, or you need decoders of other servers and formats. Please send an email to [[support@dragino.com>>mailto:support@dragino.com]]
472
473
474 = 11. Why my Dev EUI and APP EUI is 0x000000000000, how to solve? =
475
476
477 (((
478 It is possible the keys is erased during upgrading of firmware. and the console output shows below after AT+CFG
479 )))
480
481 (((
482 AT+APPKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
483 )))
484
485 (((
486 AT+NWKSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
487 )))
488
489 (((
490 AT+APPSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
491 )))
492
493 (((
494 AT+APPEUI=00 00 00 00 00 00 00 00
495 )))
496
497 (((
498
499 )))
500
501 (((
502 You can get the keys from the box sticker or send mail to Dragino Support to check keys with the provided SN number.
503 )))
504
505 (((
506 You can rewrites the keys by running commands in AT Console
507
508
509 )))
510
511 (((
512 **For example：**
513 )))
514
515 (((
516 AT+APPKEY=85 41 47 20 45 58 28 14 16 82 A0 F0 80 0D DD EE
517 )))
518
519 (((
520 AT+NWKSKEY=AA CC B0 20 30 45 37 32 14 1E 14 93 E2 3B 20 11
521 )))
522
523 (((
524 AT+APPSKEY=11 23 02 20 30 20 30 60 80 20 20 30 30 20 10 10
525 )))
526
527 (((
528 AT+APPEUI=2C 45 47 E3 24 12 23 24
529 )))
530
531 (((
532 (Any combination of 16 bit codes can be used）
533
534
535 = 12. I set my device is LoRaWAN Class C mode, why i still see Class A after boot? =
536 )))
537
538
539 Class C only refers to status after OTAA Join successfully. The OTAA Join Process will use Class A mode.
540
541
542 = 13. Why it takes longer time for OTAA joined in US915/CN470/AU915 band? =
543
544
545 In US915, AU915 or CN470 frequency band, there are 8 subbands, totally 72 channels. and LoRaWAN server normally use only one sub-band, for example Subband 2 in TTN. The gateway also configured to Subband 2 and cover eight channels in this subband. If the end node transfer data in Subband 2, it will reach to gateway and to the LoRaWAN server. If the end node transfer packets in other subbands, for example subband 1, the packet won't arrive both gateway or LoRaWAN server.
546
547
548 In Dragino Sensors old version firmware (before early 2022), the subband is fixed the subband to 2 , but this cause a problem, the end node is hard to use in other subband and need program. So the new logic is as below:
549
550 We have improved this, the end node will use frequency 1 from sub-band1, then frequency 1 from sub-band2, then frequency 1 from sub-band3, etc to process the OTAA join, In this case, In this case, the end node can support LoRaWAN servers with different subbands. To make sure the end node will only transmit the proper sub-band after OTAA Joined successfully, the end node will:
551
552 * (((
553 Check what sub-band the LoRaWAN server ask from the OTAA Join Accept message and switch to that subband
554 )))
555 * (((
556 Use the Join successful sub-band if the server doesn't include subband info in the OTAA Join Accept message ( TTN v2 doesn't include)
557 )))
558
559 This change will make the activation time a littler longer but make sure the device can be used in any subband.
560
561
562 Below is a photo to show why it takes longer time for OTAA Join. We can see in 72 channels mode, why it takes more time to join success. If users want to have faster OTAA Join success, he can change default CHE to the subband he use.
563
564
565 [[image:image-20221215223215-1.png||height="584" width="1280"]]
566
567 (% class="wikigeneratedid" %)
568