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Wiki source code of LoRaWAN Communication Debug

Version 49.1 by Mengting Qiu on 2024/01/23 16:37
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1 **~ Table of Contents:**
2
3 {{toc/}}
4
5
6
7 = z =
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 Live data in LoRaWAN Server**
48
49 * Does the gateway real-time data contain information about Join Request? If not, check the internet connection and gateway LoRaWAN server Settings.
50
51 * 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.
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-20240123150720-1.png||height="459" width="1182"]]
66
67 The data for the end device set in server
68
69
70 [[image:image-20240123150943-2.png||height="556" width="1179"]]
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-20240123151225-3.png||height="434" width="902"]]
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/ is not periodically uplink？ 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 [[image:image-20240123161737-4.png||height="395" width="763"]]
184 )))
185
186 [[image:image-20240123161853-6.png||height="599" width="771"]]
187
188 Disable Frame Counter Check in ABP Mode
189
190
191 = 5. Downstream Debug =
192
193 == 5.1 How it work ==
194
195
196 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.
197
198 (((
199 Depends on Class A or Class C, the receive windows will be a little difference.
200 )))
201
202 [[image:image-20220531161828-1.png]]
203
204 receive windows for Class A and Class C
205
206
207 Below are the requirement for the End Device to receive the packets.
208
209 * The End Device must open the receive windows: RX1 or RX2
210
211 * The LoRaWAN server must send a downstream packet, and the gateway forward this downstream packet for this end node.
212
213 * This downstream packet must arrive to the end node while RX1 or RX2 is open.
214
215 * This packet must match the frequency of the RX1 or RX2 window.
216
217 * 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.**
218
219 (% class="wikigeneratedid" %)
220 == ==
221
222 == 5.2 See Debug Info ==
223
224
225 (((
226 (% style="color:blue" %)**For LoRaWAN Server**
227 )))
228
229 (((
230 We can check if there is downlink message for this end node, use TTN for example:
231 )))
232
233 (((
234 Configure a downlink to the end device
235 )))
236
237 [[image:image-20240123163307-7.png||height="330" width="1125"]]
238
239 (((
240 Set a downstream in TTN and see it is sent
241 )))
242
243
244 (((
245 This downstream info will then pass to the gateway downstream list. and include the DR which is used (SF9BW125) in EU868 is DR3
246 )))
247
248 [[image:image-20220526164650-13.png]]
249
250 (((
251 Gateway Traffic can see this downstream info
252 )))
253
254
255
256 (((
257 (% style="color:blue" %)**For LoRaWAN Gateway**
258 )))
259
260 (((
261 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:
262 )))
263
264 [[image:image-20220526164734-14.png]]
265
266 (((
267 Gateway Sent out this packet
268 )))
269
270
271
272 (((
273 (% style="color:blue" %)**For End Node**
274 )))
275
276 (((
277 we can use AT Command (AT+CFG) to check the RX1 configure and RX2 configure. as below:
278 )))
279
280 (((
281 * (% style="color:#037691" %)**AT+RX2FQ=869525000**  (%%) **~-~-->**  The RX2 Window frequency
282
283 * (% style="color:#037691" %)**AT+RX2DR=3**          (%%) **~-~-->**  The RX2 DataRate
284
285 * (% style="color:#037691" %)**AT+RX1DL=1000**       (%%) ** ~-~-->**  Receive Delay 1
286
287 * (% style="color:#037691" %)**AT+RX2DL=2000**       (%%) **~-~--> ** Receive Delay 2
288 )))
289
290 (((
291 (% style="color:blue" %)**when the device running, we can see below info:**
292 )))
293
294 {{{ [12502]***** UpLinkCounter= 0 *****
295 [12503]TX on freq 868500000 Hz at DR 0
296 [13992]txDone
297 [15022]RX on freq 868500000 Hz at DR 0 --> RX1 window open at frequency: 868500000, DR0, after 15022-13992= 1030ms of txdone
298 [15222]rxTimeOut --> no packet arrive in RX1 window. (duration: 200ms)
299 [15987]RX on freq 869525000 Hz at DR 3 --> RX2 window open at frequency: 869525000, DR3, after 15987-13992= 1995ms of txdone
300 [16027]rxTimeOut --> no packet arrive in RX2 window. (duration: 40 ms)}}}
301
302 (((
303
304
305
306 )))
307
308 (((
309 (% style="color:blue" %)**Another message:**
310 )))
311
312 {{{ [12502]***** UpLinkCounter= 0 *****
313 [12503]TX on freq 868100000 Hz at DR 0
314 [13992]txDone
315 [15022]RX on freq 868100000 Hz at DR 0
316 [15222]rxTimeOut
317 [15987]RX on freq 869525000 Hz at DR 3
318 [16185]rxDone --> We have got the downstream packet.
319 Rssi= -64
320 Receive data
321 1:0012345678}}}
322
323
324 == 5.3 If problem doesn't solve ==
325
326
327 (% 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:**
328
329 * End node console to show the transmit freuqency and DR.
330
331 * Gateway (from gateway UI) traffic to show the packet got from end node and receive from Server.
332
333 * Gateway traffic (from server UI) to shows the data exchange between gateway and server.
334
335 * End Node traffic (from server UI) to shows end node activity in server.
336
337 = 6. Downlink Issue ~-~- Packet REJECTED, unsupported frequency =
338
339
340 (((
341 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.
342 )))
343
344 (((
345
346 )))
347
348 (((
349 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:
350 )))
351
352 {{{Sat Nov 21 08:04:17 2020 daemon.info lora_pkt_fwd[1680]: ERROR~ Packet REJECTED, unsupported frequency - 923200000 (min:865000000,max:867000000)}}}
353
354 (((
355
356 )))
357
358 (((
359 In this case, please double check the gateway frequency and the server frequency band.
360 )))
361
362
363 = 7. Decrypt a LoRaWAN Packet =
364
365
366 (% style="color:blue" %)**1. LHT65 End device configure:**
367
368 **Change to ABP Mode:  AT+NJM=0**
369
370 **Change to fix frequency:  AT+CHS=904900000**
371
372 **Change to fix DR:  AT+DR=0**
373
374
375 [[image:image-20220526165525-16.png]]
376
377
378
379 (% style="color:blue" %)**2. In LG02 , configure to receive above message**
380
381 [[image:image-20220526165612-17.png]]
382
383
384 In LG02 console, we can see the hex receive are:
385
386 [[image:image-20220526171112-21.png]]
387
388
389
390 (% style="color:blue" %)**3. Decode the info in web**
391
392 [[https:~~/~~/lorawan-packet-decoder-0ta6puiniaut.runkit.sh>>url:https://lorawan-packet-decoder-0ta6puiniaut.runkit.sh/]]
393
394 Need these three fields:
395
396 LoRa packet hex format: 40c1190126800100024926272bf18bbb6341584e27e23245 (from LG02)
397
398 AT+NWKSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 11 (End node Network Session Key)
399
400 AT+APPSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 11 (End Node App Session Key)
401
402
403 [[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]]
404
405 [[image:image-20220526171029-20.png]]
406
407 (((
408 The FRMPayload is the device payload.
409 )))
410
411
412 = 8. Why i see uplink 0x00 periodcally on the LHT65 v1.8 firmware =
413
414
415 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.
416
417
418 = 9. Why do I see a "MIC Mismatch" error message from the server? =
419
420
421 (((
422 1)  If the user receives a "MIC Mismatch" message after registering the node on the server.
423 )))
424
425 (((
426 It is likely that the user filled in the wrong APPKEY when registering the node. Many users fill in "APPSKEY".
427 )))
428
429 * (((
430 Please note the distinction between "APPKEY" and "APPSKEY".
431 )))
432
433 (((
434 2）If the node works on the server for a period of time, the device stops working and receives a "MIC Mismatch" message.
435 )))
436
437 (((
438 The user needs a USB-TTL adapter to connect the serial port to modify the node APPKEY.
439 )))
440
441 * (((
442 If a node is registered with multiple servers, it may also cause the "mic mismatch" error.
443 )))
444
445 (% class="wikigeneratedid" %)
446 3）Wrong Regional Parameters version selected
447 We generally use versions above 1.0.2
448
449 (% class="wikigeneratedid" %)
450 [[image:image-20230322163227-1.png]]
451
452 (% class="wikigeneratedid" %)
453 4）We have had cases where it was automatically fixed the next day despite no manual changes, probably a server side issue
454
455
456 = 10. Why i got the payload only with "0x00" or "AA~=~="? =
457
458
459 (% style="color:blue" %)**Why sensor sends 0x00?**
460
461 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.
462
463 **Possible Case 1**:
464
465 Sensor has ADR=1 enable and sensor need to reply server MAC command (ADR request) while sensor has DR=0.
466
467
468 **Possible Case 2:**
469
470 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.
471
472
473 (% style="color:blue" %)**How to solve:**
474
475 Solution:
476
477 ~1. Use the decoder to filter out this 0x00 packet. (**Recommand**)
478
479 2. Data rate changed from DR3 to DR5, increasing upload byte length
480 AT+ADR=0
481 AT+DR=3
482
483 Downlink：
484
485 [[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]]
486
487 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]]
488
489
490 = 11. Why my Dev EUI and APP EUI is 0x000000000000, how to solve? =
491
492
493 (((
494 It is possible the keys is erased during upgrading of firmware. and the console output shows below after AT+CFG
495 )))
496
497 (((
498 AT+APPKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
499 )))
500
501 (((
502 AT+NWKSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
503 )))
504
505 (((
506 AT+APPSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
507 )))
508
509 (((
510 AT+APPEUI=00 00 00 00 00 00 00 00
511 )))
512
513 (((
514
515 )))
516
517 (((
518 You can get the keys from the box sticker or send mail to Dragino Support to check keys with the provided SN number.
519 )))
520
521 (((
522 You can rewrites the keys by running commands in AT Console
523
524
525 )))
526
527 (((
528 **For example：**
529 )))
530
531 (((
532 AT+APPKEY=85 41 47 20 45 58 28 14 16 82 A0 F0 80 0D DD EE
533 )))
534
535 (((
536 AT+NWKSKEY=AA CC B0 20 30 45 37 32 14 1E 14 93 E2 3B 20 11
537 )))
538
539 (((
540 AT+APPSKEY=11 23 02 20 30 20 30 60 80 20 20 30 30 20 10 10
541 )))
542
543 (((
544 AT+APPEUI=2C 45 47 E3 24 12 23 24
545 )))
546
547 (((
548 (Any combination of 16 bit codes can be used）
549
550
551 = 12. I set my device is LoRaWAN Class C mode, why i still see Class A after boot? =
552 )))
553
554
555 Class C only refers to status after OTAA Join successfully. The OTAA Join Process will use Class A mode.
556
557
558 = 13. Why it takes longer time for OTAA joined in US915/CN470/AU915 band? =
559
560
561 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.
562
563
564 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:
565
566 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:
567
568 * (((
569 Check what sub-band the LoRaWAN server ask from the OTAA Join Accept message and switch to that subband
570 )))
571 * (((
572 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)
573 )))
574
575 This change will make the activation time a littler longer but make sure the device can be used in any subband.
576
577
578 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.
579
580
581 [[image:image-20221215223215-1.png||height="584" width="1280"]]
582
583 (% class="wikigeneratedid" %)
584