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Wiki source code of LoRaWAN Communication Debug

Version 62.1 by Mengting Qiu on 2024/01/29 15:43
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1 **~ Table of Contents:**
2
3 {{toc/}}
4
5
6
7 = 1. Join process page check =
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-20240129142147-2.png||height="736" width="964"]]
30
31 Console Output from End device to see the transmit frequency.
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-20240129151608-6.jpeg||height="725" width="1256"]]
41
42 Console Output from Gateway to see packets between end node and server.
43
44
45 (% style="color:blue" %)**3. Gateway Live data in LoRaWAN Server**
46
47 * Does the gateway real-time data contain information about Join Request? If not, check the internet connection and gateway LoRaWAN server Settings.
48
49 * 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.
50
51 * 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.
52
53 [[image:image-20240129150821-5.jpeg||height="522" width="1264"]]
54
55 The Traffic for the End node in the server, use TTN as example.
56
57
58 (% style="color:blue" %)**4. Data Page in LoRaWAN server**
59
60 * 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.
61
62 [[image:image-20240129142557-3.png||height="488" width="1267"]]
63
64 The data for the end device set in server
65
66
67 [[image:image-20240129142631-4.png||height="637" width="1256"]]
68
69 Check if OTAA Keys match the keys in device.
70
71
72 = 2. Notice of US915/CN470/AU915 Frequency band =
73
74
75 (((
76 If user has problem to work with LoRaWAN server in band US915/AU915/CN470, he can check:
77 )))
78
79 * (((
80 What **sub-band** the server support?
81 )))
82 * (((
83 What is the **sub-band** the gateway support?
84 )))
85 * (((
86 What is the **sub-band** the end node is using?
87 )))
88
89 (((
90 All of above should match so End Node can properly Join the server and don't have packet lost.
91 )))
92
93 (((
94
95 )))
96
97 (((
98 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.
99 )))
100
101 (((
102
103 )))
104
105 (((
106 Here are the frequency tables for these bands as reference:
107 )))
108
109 [[image:image-20220526163801-6.png]]
110
111 US915 Channels
112
113
114 [[image:image-20220526163926-7.png]]
115
116 AU915 Channels
117
118
119 [[image:image-20220526163941-8.png]]
120
121 (((
122 CN470 Channels
123
124
125 )))
126
127 (((
128 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.
129 )))
130
131 [[image:image-20240123151225-3.png||height="434" width="902"]]
132
133 (((
134 TTN FREQUENCY PLAN
135
136 (% style="display:none" %) (%%)
137 )))
138
139 (((
140 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. )
141 )))
142
143 (% style="display:none" %) (%%)
144
145 = 3. Why I see data lost/ is not periodically uplink？ Even the signal strength is good =
146
147
148 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:
149
150 * (% 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.
151
152 * (% 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.
153
154 * (% 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.
155
156 (((
157 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.
158 )))
159
160
161 (((
162 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.
163 )))
164
165
166 = 4. Transmision on ABP Mode =
167
168
169 (((
170 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.
171 )))
172
173 (((
174 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.
175 )))
176
177 (((
178 To solve this, disable the Frame Counter Check will solve this issue , or reset the frame counter in the device page.
179
180 [[image:image-20240123161737-4.png||height="395" width="763"]]
181 )))
182
183 [[image:image-20240123161853-6.png||height="599" width="771"]]
184
185 Disable Frame Counter Check in ABP Mode
186
187
188 = 5. Downstream Debug =
189
190 == 5.1 How it work ==
191
192
193 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.
194
195 (((
196 Depends on Class A or Class C, the receive windows will be a little difference.
197 )))
198
199 [[image:image-20220531161828-1.png]]
200
201 receive windows for Class A and Class C
202
203
204 Below are the requirement for the End Device to receive the packets.
205
206 * The End Device must open the receive windows: RX1 or RX2
207
208 * The LoRaWAN server must send a downstream packet, and the gateway forward this downstream packet for this end node.
209
210 * This downstream packet must arrive to the end node while RX1 or RX2 is open.
211
212 * This packet must match the frequency of the RX1 or RX2 window.
213
214 * 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.**
215
216 == 5.2 See Debug Info ==
217
218
219 (((
220 (% style="color:blue" %)**For LoRaWAN Server**
221 )))
222
223 (((
224 We can check if there is downlink message for this end node, use TTN for example:
225 )))
226
227 (((
228 Configure a downlink to the end device
229
230 [[image:image-20240129152412-8.png||height="486" width="1206"]]
231 )))
232
233 [[image:image-20240123163307-7.png||height="330" width="1125"]]
234
235 (((
236 Set a downstream in TTN and see it is sent
237 )))
238
239
240 (((
241 This downstream info will then pass to the gateway downstream list. and the DR which is used (SF7BW500) in US915 is DR5.
242 )))
243
244 [[image:image-20240129152049-7.png||height="463" width="1166"]]
245
246 (((
247 Gateway Traffic can see this downstream info
248 )))
249
250
251
252 (((
253 (% style="color:blue" %)**For LoRaWAN Gateway**
254 )))
255
256 (((
257 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:
258 )))
259
260 [[image:image-20220526164734-14.png]]
261
262 (((
263 Gateway Sent out this packet
264 )))
265
266
267
268 (((
269 (% style="color:blue" %)**For End Node**
270 )))
271
272 (((
273 we can use AT Command (AT+CFG) to check the RX1 configure and RX2 configure. as below:
274 )))
275
276 (((
277 * (% style="color:#037691" %)**AT+RX2FQ=869525000**  (%%) **~-~-->**  The RX2 Window frequency
278
279 * (% style="color:#037691" %)**AT+RX2DR=3**          (%%) **~-~-->**  The RX2 DataRate
280
281 * (% style="color:#037691" %)**AT+RX1DL=1000**       (%%) ** ~-~-->**  Receive Delay 1
282
283 * (% style="color:#037691" %)**AT+RX2DL=2000**       (%%) **~-~--> ** Receive Delay 2
284 )))
285
286 (((
287 (% style="color:blue" %)**when the device running, we can see below info:**
288 )))
289
290 {{{ [12502]***** UpLinkCounter= 0 *****
291 [12503]TX on freq 868500000 Hz at DR 0
292 [13992]txDone
293 [15022]RX on freq 868500000 Hz at DR 0 --> RX1 window open at frequency: 868500000, DR0, after 15022-13992= 1030ms of txdone
294 [15222]rxTimeOut --> no packet arrive in RX1 window. (duration: 200ms)
295 [15987]RX on freq 869525000 Hz at DR 3 --> RX2 window open at frequency: 869525000, DR3, after 15987-13992= 1995ms of txdone
296 [16027]rxTimeOut --> no packet arrive in RX2 window. (duration: 40 ms)}}}
297
298 (((
299
300
301
302 )))
303
304 (((
305 (% style="color:blue" %)**Another message:**
306 )))
307
308 {{{ [12502]***** UpLinkCounter= 0 *****
309 [12503]TX on freq 868100000 Hz at DR 0
310 [13992]txDone
311 [15022]RX on freq 868100000 Hz at DR 0
312 [15222]rxTimeOut
313 [15987]RX on freq 869525000 Hz at DR 3
314 [16185]rxDone --> We have got the downstream packet.
315 Rssi= -64
316 Receive data
317 1:0012345678}}}
318
319
320 == 5.3 If problem doesn't solve ==
321
322
323 (% 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:**
324
325 * End node console to show the transmit freuqency and DR.
326
327 * Gateway (from gateway UI) traffic to show the packet got from end node and receive from Server.
328
329 * Gateway traffic (from server UI) to shows the data exchange between gateway and server.
330
331 * End Node traffic (from server UI) to shows end node activity in server.
332
333 = 6. Downlink Issue ~-~- Packet REJECTED, unsupported frequency =
334
335
336 (((
337 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.
338 )))
339
340 (((
341
342 )))
343
344 (((
345 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:
346 )))
347
348 {{{Sat Nov 21 08:04:17 2020 daemon.info lora_pkt_fwd[1680]: ERROR~ Packet REJECTED, unsupported frequency - 923200000 (min:865000000,max:867000000)}}}
349
350 (((
351
352 )))
353
354 (((
355 In this case, please double check the gateway frequency and the server frequency band.
356 )))
357
358
359 = 7. Decrypt a LoRaWAN Packet =
360
361
362 (% style="color:blue" %)**1. LHT65 End device configure:**
363
364 **Change to ABP Mode:  AT+NJM=0**
365
366 **Change to fix frequency:  AT+CHS=904900000**
367
368 **Change to fix DR:  AT+DR=0**
369
370
371 [[image:image-20220526165525-16.png]]
372
373
374
375 (% style="color:blue" %)**2. In LG02 , configure to receive above message**
376
377 [[image:image-20220526165612-17.png]]
378
379
380 In LG02 console, we can see the hex receive are:
381
382 [[image:image-20220526171112-21.png]]
383
384
385
386 (% style="color:blue" %)**3. Decode the info in web**
387
388 [[https:~~/~~/lorawan-packet-decoder-0ta6puiniaut.runkit.sh>>url:https://lorawan-packet-decoder-0ta6puiniaut.runkit.sh/]]
389
390 Need these three fields:
391
392 LoRa packet hex format: 40c1190126800100024926272bf18bbb6341584e27e23245 (from LG02)
393
394 AT+NWKSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 11 (End node Network Session Key)
395
396 AT+APPSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 11 (End Node App Session Key)
397
398
399 [[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]]
400
401 [[image:image-20220526171029-20.png]]
402
403 (((
404 The FRMPayload is the device payload.
405 )))
406
407
408 = 8. Why I see uplink 0x00 periodically on the LHT65 v1.8 firmware =
409
410
411 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.
412
413
414 = 9. Why do I see a "MIC Mismatch" error message from the server? =
415
416
417 (((
418 1)  If the user receives a "MIC Mismatch" message after registering the node on the server.
419 )))
420
421 (((
422 It is likely that the user filled in the wrong APPKEY when registering the node. Many users fill in "APPSKEY".
423 )))
424
425 * (((
426 Please note the distinction between "APPKEY" and "APPSKEY".
427 )))
428
429 (((
430 2）If the node works on the server for a period of time, the device stops working and receives a "MIC Mismatch" message.
431 )))
432
433 (((
434 The user needs a USB-TTL adapter to connect the serial port to modify the node APPKEY.
435 )))
436
437 * (((
438 If a node is registered with multiple servers, it may also cause the "mic mismatch" error.
439 )))
440
441 (% class="wikigeneratedid" %)
442 3）Wrong Regional Parameters version selected
443 We generally use versions above 1.0.2
444
445 (% class="wikigeneratedid" %)
446 [[image:image-20230322163227-1.png]]
447
448 (% class="wikigeneratedid" %)
449 4）We have had cases where it was automatically fixed the next day despite no manual changes, probably a server side issue
450
451
452 = 10. Why i got the payload only with "0x00" or "AA~=~="? =
453
454
455 (% style="color:blue" %)**Why sensor sends 0x00?**
456
457 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.
458
459 **Possible Case 1**:
460
461 Sensor has ADR=1 enable and sensor need to reply server MAC command (ADR request) while sensor has DR=0.
462
463
464 **Possible Case 2:**
465
466 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.
467
468
469 (% style="color:blue" %)**How to solve:**
470
471 Solution:
472
473 ~1. Use the decoder to filter out this 0x00 packet. (**Recommand**)
474
475 2. Data rate changed from DR3 to DR5, increasing upload byte length
476 AT+ADR=0
477 AT+DR=3
478
479 Downlink：
480
481 [[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]]
482
483 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]]
484
485
486 = 11. Why my Dev EUI and APP EUI is 0x000000000000, how to solve? =
487
488
489 (((
490 It is possible the keys is erased during upgrading of firmware. and the console output shows below after AT+CFG
491 )))
492
493 (((
494 AT+APPKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
495 )))
496
497 (((
498 AT+NWKSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
499 )))
500
501 (((
502 AT+APPSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
503 )))
504
505 (((
506 AT+APPEUI=00 00 00 00 00 00 00 00
507 )))
508
509 (((
510
511 )))
512
513 (((
514 You can get the keys from the box sticker or send mail to Dragino Support to check keys with the provided SN number.
515 )))
516
517 (((
518 You can rewrites the keys by running commands in AT Console
519
520
521 )))
522
523 (((
524 **For example：**
525 )))
526
527 (((
528 AT+APPKEY=85 41 47 20 45 58 28 14 16 82 A0 F0 80 0D DD EE
529 )))
530
531 (((
532 AT+NWKSKEY=AA CC B0 20 30 45 37 32 14 1E 14 93 E2 3B 20 11
533 )))
534
535 (((
536 AT+APPSKEY=11 23 02 20 30 20 30 60 80 20 20 30 30 20 10 10
537 )))
538
539 (((
540 AT+APPEUI=2C 45 47 E3 24 12 23 24
541 )))
542
543 (((
544 (Any combination of 16 bit codes can be used）
545
546
547 = 12. I set my device is LoRaWAN Class C mode, why i still see Class A after boot? =
548 )))
549
550
551 Class C only refers to status after OTAA Join successfully. The OTAA Join Process will use Class A mode.
552
553
554 = 13. Why it takes longer time for OTAA joined in US915/CN470/AU915 band? =
555
556
557 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.
558
559
560 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:
561
562 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:
563
564 * (((
565 Check what sub-band the LoRaWAN server ask from the OTAA Join Accept message and switch to that sub-band.
566 )))
567 * (((
568 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).
569 )))
570
571 This change will make the activation time a little longer but make sure the device can be used in any sub-band.
572
573
574 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.
575
576
577 [[image:image-20221215223215-1.png||height="584" width="1280"]]
578
579 (% class="wikigeneratedid" %)
580