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Wiki source code of LoRaWAN Communication Debug

Version 50.1 by Mengting Qiu on 2024/01/23 17:11
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1 **~ Table of Contents:**
2
3 {{toc/}}
4
5
6
7 = 1.Join process page check =
8
9 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.
10 \\**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:**
11
12 * End node console to show the Join freuqency and DR. (If possible)
13
14 * Gateway (from gateway UI) traffic to show the packet got from end node and receive from Server. (If possible)
15
16 * Gateway traffic (from server UI) to shows the data exchange between gateway and server. (Normaly possible)
17
18 * End Node traffic (from server UI) to shows end node activity in server. (Normaly possible)
19
20 * 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)
21
22 (% style="color:blue" %)**1. End Device Join Screen shot, we can check:**
23
24 * If the device is sending join request to server?
25
26 * What frequency the device is sending?
27
28 [[image:image-20220526164956-15.png||height="591" width="1153"]]
29
30 Console Output from End device to see the transmit frequency
31
32
33
34 (% style="color:blue" %)**2. Gateway packet traffic in gateway web or ssh. we can check:**
35
36 * If the gateway receive the Join request packet from sensor? (If this fail, check if the gateway and sensor works on the match frequency)
37
38 * If the gateway gets the Join Accept message from server and transmit it via LoRa?
39
40 [[image:image-20220526163608-2.png]]
41
42 Console Output from Gateway to see packets between end node and server.
43
44
45
46 (% style="color:blue" %)**3. Gateway Live data in LoRaWAN Server**
47
48 * Does the gateway real-time data contain information about Join Request? If not, check the internet connection and gateway LoRaWAN server Settings.
49
50 * Does the server send back a Join Accept for the Join Request? If not, check that the key from the device matches the key you put into the server, or try to choose a different server route for that end device.
51
52 * 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.
53
54 [[image:image-20220526163633-3.png]]
55
56 The Traffic for the End node in the server, use TTN as example.
57
58
59
60 (% style="color:blue" %)**4. Data Page in LoRaWAN server**
61
62 * 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.
63
64 [[image:image-20240123150720-1.png||height="459" width="1182"]]
65
66 The data for the end device set in server
67
68
69 [[image:image-20240123150943-2.png||height="556" width="1179"]]
70
71 Check if OTAA Keys match the keys in device.
72
73
74 = 2. Notice of US915/CN470/AU915 Frequency band =
75
76
77 (((
78 If user has problem to work with LoRaWAN server in band US915/AU915/CN470, he can check:
79 )))
80
81 * (((
82 What **sub-band** the server support?
83 )))
84 * (((
85 What is the **sub-band** the gateway support?
86 )))
87 * (((
88 What is the **sub-band** the end node is using?
89 )))
90
91 (((
92 All of above should match so End Node can properly Join the server and don't have packet lost.
93 )))
94
95 (((
96
97 )))
98
99 (((
100 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.
101 )))
102
103 (((
104
105 )))
106
107 (((
108 Here are the frequency tables for these bands as reference:
109 )))
110
111 [[image:image-20220526163801-6.png]]
112
113 US915 Channels
114
115
116 [[image:image-20220526163926-7.png]]
117
118 AU915 Channels
119
120
121 [[image:image-20220526163941-8.png]]
122
123 (((
124 CN470 Channels
125
126
127 )))
128
129 (((
130 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.
131 )))
132
133 [[image:image-20240123151225-3.png||height="434" width="902"]]
134
135 (((
136 TTN FREQUENCY PLAN
137
138 (% style="display:none" %) (%%)
139 )))
140
141 (((
142 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. )
143 )))
144
145 (% style="display:none" %) (%%)
146
147 = 3. Why I see data lost/ is not periodically uplink？ Even the signal strength is good =
148
149
150 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:
151
152 * (% 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.
153
154 * (% 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.
155
156 * (% 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.
157
158 (((
159 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.
160 )))
161
162
163 (((
164 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.
165 )))
166
167
168 = 4. Transmision on ABP Mode =
169
170
171 (((
172 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.
173 )))
174
175 (((
176 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.
177 )))
178
179 (((
180 To solve this, disable the Frame Counter Check will solve this issue , or reset the frame counter in the device page.
181
182 [[image:image-20240123161737-4.png||height="395" width="763"]]
183 )))
184
185 [[image:image-20240123161853-6.png||height="599" width="771"]]
186
187 Disable Frame Counter Check in ABP Mode
188
189
190 = 5. Downstream Debug =
191
192 == 5.1 How it work ==
193
194
195 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.
196
197 (((
198 Depends on Class A or Class C, the receive windows will be a little difference.
199 )))
200
201 [[image:image-20220531161828-1.png]]
202
203 receive windows for Class A and Class C
204
205
206 Below are the requirement for the End Device to receive the packets.
207
208 * The End Device must open the receive windows: RX1 or RX2
209
210 * The LoRaWAN server must send a downstream packet, and the gateway forward this downstream packet for this end node.
211
212 * This downstream packet must arrive to the end node while RX1 or RX2 is open.
213
214 * This packet must match the frequency of the RX1 or RX2 window.
215
216 * 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.**
217
218 == ==
219
220 == 5.2 See Debug Info ==
221
222
223 (((
224 (% style="color:blue" %)**For LoRaWAN Server**
225 )))
226
227 (((
228 We can check if there is downlink message for this end node, use TTN for example:
229 )))
230
231 (((
232 Configure a downlink to the end device
233 )))
234
235 [[image:image-20240123163307-7.png||height="330" width="1125"]]
236
237 (((
238 Set a downstream in TTN and see it is sent
239 )))
240
241
242 (((
243 This downstream info will then pass to the gateway downstream list. and include the DR which is used (SF9BW125) in EU868 is DR3
244 )))
245
246 [[image:image-20220526164650-13.png]]
247
248 (((
249 Gateway Traffic can see this downstream info
250 )))
251
252
253
254 (((
255 (% style="color:blue" %)**For LoRaWAN Gateway**
256 )))
257
258 (((
259 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:
260 )))
261
262 [[image:image-20220526164734-14.png]]
263
264 (((
265 Gateway Sent out this packet
266 )))
267
268
269
270 (((
271 (% style="color:blue" %)**For End Node**
272 )))
273
274 (((
275 we can use AT Command (AT+CFG) to check the RX1 configure and RX2 configure. as below:
276 )))
277
278 (((
279 * (% style="color:#037691" %)**AT+RX2FQ=869525000**  (%%) **~-~-->**  The RX2 Window frequency
280
281 * (% style="color:#037691" %)**AT+RX2DR=3**          (%%) **~-~-->**  The RX2 DataRate
282
283 * (% style="color:#037691" %)**AT+RX1DL=1000**       (%%) ** ~-~-->**  Receive Delay 1
284
285 * (% style="color:#037691" %)**AT+RX2DL=2000**       (%%) **~-~--> ** Receive Delay 2
286 )))
287
288 (((
289 (% style="color:blue" %)**when the device running, we can see below info:**
290 )))
291
292 {{{ [12502]***** UpLinkCounter= 0 *****
293 [12503]TX on freq 868500000 Hz at DR 0
294 [13992]txDone
295 [15022]RX on freq 868500000 Hz at DR 0 --> RX1 window open at frequency: 868500000, DR0, after 15022-13992= 1030ms of txdone
296 [15222]rxTimeOut --> no packet arrive in RX1 window. (duration: 200ms)
297 [15987]RX on freq 869525000 Hz at DR 3 --> RX2 window open at frequency: 869525000, DR3, after 15987-13992= 1995ms of txdone
298 [16027]rxTimeOut --> no packet arrive in RX2 window. (duration: 40 ms)}}}
299
300 (((
301
302
303
304 )))
305
306 (((
307 (% style="color:blue" %)**Another message:**
308 )))
309
310 {{{ [12502]***** UpLinkCounter= 0 *****
311 [12503]TX on freq 868100000 Hz at DR 0
312 [13992]txDone
313 [15022]RX on freq 868100000 Hz at DR 0
314 [15222]rxTimeOut
315 [15987]RX on freq 869525000 Hz at DR 3
316 [16185]rxDone --> We have got the downstream packet.
317 Rssi= -64
318 Receive data
319 1:0012345678}}}
320
321
322 == 5.3 If problem doesn't solve ==
323
324
325 (% 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:**
326
327 * End node console to show the transmit freuqency and DR.
328
329 * Gateway (from gateway UI) traffic to show the packet got from end node and receive from Server.
330
331 * Gateway traffic (from server UI) to shows the data exchange between gateway and server.
332
333 * End Node traffic (from server UI) to shows end node activity in server.
334
335 = 6. Downlink Issue ~-~- Packet REJECTED, unsupported frequency =
336
337
338 (((
339 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.
340 )))
341
342 (((
343
344 )))
345
346 (((
347 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:
348 )))
349
350 {{{Sat Nov 21 08:04:17 2020 daemon.info lora_pkt_fwd[1680]: ERROR~ Packet REJECTED, unsupported frequency - 923200000 (min:865000000,max:867000000)}}}
351
352 (((
353
354 )))
355
356 (((
357 In this case, please double check the gateway frequency and the server frequency band.
358 )))
359
360
361 = 7. Decrypt a LoRaWAN Packet =
362
363
364 (% style="color:blue" %)**1. LHT65 End device configure:**
365
366 **Change to ABP Mode:  AT+NJM=0**
367
368 **Change to fix frequency:  AT+CHS=904900000**
369
370 **Change to fix DR:  AT+DR=0**
371
372
373 [[image:image-20220526165525-16.png]]
374
375
376
377 (% style="color:blue" %)**2. In LG02 , configure to receive above message**
378
379 [[image:image-20220526165612-17.png]]
380
381
382 In LG02 console, we can see the hex receive are:
383
384 [[image:image-20220526171112-21.png]]
385
386
387
388 (% style="color:blue" %)**3. Decode the info in web**
389
390 [[https:~~/~~/lorawan-packet-decoder-0ta6puiniaut.runkit.sh>>url:https://lorawan-packet-decoder-0ta6puiniaut.runkit.sh/]]
391
392 Need these three fields:
393
394 LoRa packet hex format: 40c1190126800100024926272bf18bbb6341584e27e23245 (from LG02)
395
396 AT+NWKSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 11 (End node Network Session Key)
397
398 AT+APPSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 11 (End Node App Session Key)
399
400
401 [[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]]
402
403 [[image:image-20220526171029-20.png]]
404
405 (((
406 The FRMPayload is the device payload.
407 )))
408
409
410 = 8. Why I see uplink 0x00 periodically on the LHT65 v1.8 firmware =
411
412
413 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.
414
415
416 = 9. Why do I see a "MIC Mismatch" error message from the server? =
417
418
419 (((
420 1)  If the user receives a "MIC Mismatch" message after registering the node on the server.
421 )))
422
423 (((
424 It is likely that the user filled in the wrong APPKEY when registering the node. Many users fill in "APPSKEY".
425 )))
426
427 * (((
428 Please note the distinction between "APPKEY" and "APPSKEY".
429 )))
430
431 (((
432 2）If the node works on the server for a period of time, the device stops working and receives a "MIC Mismatch" message.
433 )))
434
435 (((
436 The user needs a USB-TTL adapter to connect the serial port to modify the node APPKEY.
437 )))
438
439 * (((
440 If a node is registered with multiple servers, it may also cause the "mic mismatch" error.
441 )))
442
443 (% class="wikigeneratedid" %)
444 3）Wrong Regional Parameters version selected
445 We generally use versions above 1.0.2
446
447 (% class="wikigeneratedid" %)
448 [[image:image-20230322163227-1.png]]
449
450 (% class="wikigeneratedid" %)
451 4）We have had cases where it was automatically fixed the next day despite no manual changes, probably a server side issue
452
453
454 = 10. Why i got the payload only with "0x00" or "AA~=~="? =
455
456
457 (% style="color:blue" %)**Why sensor sends 0x00?**
458
459 For US915, AU915 or AS923 frequencies, the max payload lenght is 11 bytes for DR0. Some times sensor needs to send MAC command to server, because the payload is 11 bytes, The MAC command + Payload will exceed 11 bytes and LoRaWAN server will ignore the uplink. In this case, Sensor will send two uplinks together: one uplink is the payload without MAC command, another uplink is **0x00 payload + MAC Command.**  For the second uplink, in the server side, it will shows the payload is 0x00. Normally, there are several case this will happen.
460
461 **Possible Case 1**:
462
463 Sensor has ADR=1 enable and sensor need to reply server MAC command (ADR request) while sensor has DR=0.
464
465
466 **Possible Case 2:**
467
468 For the sensor which has Datalog Feature enable, the sensor will send TimeRequest MAC Command to sync the time. This Time Request will be sent once Sensor Join Network and Every 10 days. While they send such command with DR=0, sensor will send this command with 0x00 payload.
469
470
471 (% style="color:blue" %)**How to solve:**
472
473 Solution:
474
475 ~1. Use the decoder to filter out this 0x00 packet. (**Recommand**)
476
477 2. Data rate changed from DR3 to DR5, increasing upload byte length
478 AT+ADR=0
479 AT+DR=3
480
481 Downlink：
482
483 [[http:~~/~~/wiki.dragino.com/xwiki/bin/view/Main/End%20Device%20AT%20Commands%20and%20Downlink%20Command/#H7.4DataRate>>http://wiki.dragino.com/xwiki/bin/view/Main/End%20Device%20AT%20Commands%20and%20Downlink%20Command/#H7.4DataRate]]
484
485 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]]
486
487
488 = 11. Why my Dev EUI and APP EUI is 0x000000000000, how to solve? =
489
490
491 (((
492 It is possible the keys is erased during upgrading of firmware. and the console output shows below after AT+CFG
493 )))
494
495 (((
496 AT+APPKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
497 )))
498
499 (((
500 AT+NWKSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
501 )))
502
503 (((
504 AT+APPSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
505 )))
506
507 (((
508 AT+APPEUI=00 00 00 00 00 00 00 00
509 )))
510
511 (((
512
513 )))
514
515 (((
516 You can get the keys from the box sticker or send mail to Dragino Support to check keys with the provided SN number.
517 )))
518
519 (((
520 You can rewrites the keys by running commands in AT Console
521
522
523 )))
524
525 (((
526 **For example：**
527 )))
528
529 (((
530 AT+APPKEY=85 41 47 20 45 58 28 14 16 82 A0 F0 80 0D DD EE
531 )))
532
533 (((
534 AT+NWKSKEY=AA CC B0 20 30 45 37 32 14 1E 14 93 E2 3B 20 11
535 )))
536
537 (((
538 AT+APPSKEY=11 23 02 20 30 20 30 60 80 20 20 30 30 20 10 10
539 )))
540
541 (((
542 AT+APPEUI=2C 45 47 E3 24 12 23 24
543 )))
544
545 (((
546 (Any combination of 16 bit codes can be used）
547
548
549 = 12. I set my device is LoRaWAN Class C mode, why i still see Class A after boot? =
550 )))
551
552
553 Class C only refers to status after OTAA Join successfully. The OTAA Join Process will use Class A mode.
554
555
556 = 13. Why it takes longer time for OTAA joined in US915/CN470/AU915 band? =
557
558
559 In US915, AU915 or CN470 frequency band, there are 8 sub-bands, totally 72 channels. and LoRaWAN server normally use only one sub-band, for example Sub-band 2 in TTN. The gateway also configured to Sub-band 2 and cover eight channels in this sub-band. If the end node transfer data in Sub-band 2, it will reach to gateway and to the LoRaWAN server. If the end node transfer packets in other sub-bands, for example sub-band 1, the packet won't arrive both gateway or LoRaWAN server.
560
561
562 In Dragino Sensors old version firmware (before early 2022), the sub-band is fixed the sub-band 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:
563
564 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 sub-bands. To make sure the end node will only transmit the proper sub-band after OTAA Joined successfully, the end node will:
565
566 * (((
567 Check what sub-band the LoRaWAN server ask from the OTAA Join Accept message and switch to that sub-band.
568 )))
569 * (((
570 Use the Join successful sub-band if the server doesn't include sub-band info in the OTAA Join Accept message (TTN v2 doesn't include).
571 )))
572
573 This change will make the activation time a little longer but make sure the device can be used in any sub-band.
574
575
576 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 sub-band he uses.
577
578
579 [[image:image-20221215223215-1.png||height="584" width="1280"]]
580
581 (% class="wikigeneratedid" %)
582