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Wiki source code of LoRaWAN Communication Debug

Version 33.1 by Edwin Chen on 2022/10/19 23:11
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1 **~ Table of Contents:**
2
3 {{toc/}}
4
5
6
7 = 1. 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 * Gateway (from gateway UI) traffic to show the packet got from end node and receive from Server. (If possible)
15 * Gateway traffic (from server UI) to shows the data exchange between gateway and server. (Normaly possible)
16 * End Node traffic (from server UI) to shows end node activity in server. (Normaly possible)
17 * 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)
18
19
20 (% style="color:blue" %)**1. End Device Join Screen shot, we can check:**
21
22 * If the device is sending join request to server?
23 * What frequency the device is sending?
24
25 [[image:image-20220526164956-15.png]]
26
27 Console Output from End device to see the transmit frequency
28
29
30
31 (% style="color:blue" %)**2. Gateway packet traffic in gateway web or ssh. we can check:**
32
33 * If the gateway receive the Join request packet from sensor? (If this fail, check if the gateway and sensor works on the match frequency)
34 * If the gateway gets the Join Accept message from server and transmit it via LoRa?
35
36 [[image:image-20220526163608-2.png]]
37
38 Console Output from Gateway to see packets between end node and server.
39
40
41 (% style="color:blue" %)**3. Gateway Traffic Page in LoRaWAN Server**
42
43 * If the Join Request packet arrive the gateway traffic in server? If not, check the internet connection and gateway LoRaWAN server settings.
44 * 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.
45 * 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.
46
47 [[image:image-20220526163633-3.png]]
48
49 The Traffic for the End node in the server, use TTN as example
50
51
52 (% style="color:blue" %)**4. Data Page in LoRaWAN server**
53
54 * 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.
55
56 [[image:image-20220526163704-4.png]]
57
58 The data for the end device set in server
59
60 [[image:image-20220526163732-5.png]]
61
62 Check if OTAA Keys match the keys in device
63
64
65
66 = 2. Notice of US915/CN470/AU915 Frequency band =
67
68
69 (((
70 If user has problem to work with lorawan server in band US915/AU915/CN470, he can check:
71 )))
72
73 * (((
74 What **sub-band** the server support ?
75 )))
76 * (((
77 What is the **sub-band** the gateway support ?
78 )))
79 * (((
80 What is the **sub-band** the end node is using ?
81 )))
82
83 (((
84 All of above should match so End Node can properly Join the server and don't have packet lost.
85 )))
86
87 (((
88
89 )))
90
91 (((
92 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.
93 )))
94
95 (((
96
97 )))
98
99 (((
100 Here are the freuqency tables for these bands as reference:
101 )))
102
103 [[image:image-20220526163801-6.png]]
104
105 US915 Channels
106
107 [[image:image-20220526163926-7.png]]
108
109 AU915 Channels
110
111
112 [[image:image-20220526163941-8.png]]
113
114 (((
115 CN470 Channels
116
117
118 )))
119
120 (((
121 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.
122 )))
123
124 [[image:image-20220526164052-9.png]]
125
126 (((
127 TTN FREQUENCY PLAN
128
129
130 )))
131
132 (((
133 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. )
134 )))
135
136
137
138 = 3. Why i see data lost/unperiocially uplink data? Even the signal strength is good =
139
140
141 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:
142
143 * **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.
144 * **Gateway** ~-~-> Use Sub-band2 (Channel 8,9,10,11,12,13,14,15) for Dragino Gateway. this is the default settings for dragino sensors.
145 * **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.
146
147 (((
148 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.
149 )))
150
151 (((
152
153 )))
154
155 (((
156 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.
157 )))
158
159
160
161 = 4. Transmision on ABP Mode =
162
163
164 (((
165 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.
166 )))
167
168 (((
169
170 )))
171
172 (((
173 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.
174 )))
175
176 (((
177
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
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 * The LoRaWAN server must send a downstream packet, and the gateway forward this downstream packet for this end node.
210 * This downstream packet must arrive to the end node while RX1 or RX2 is open.
211 * This packet must match the frequency of the RX1 or RX2 window.
212 * 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.**
213
214
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 downstream to the end device
229 )))
230
231 [[image:image-20220526164623-12.png]]
232
233 (((
234 Set a downstream in TTN and see it is sent
235 )))
236
237
238 (((
239 This downstream info will then pass to the gateway downstream list. and include the DR which is used (SF9BW125) in EU868 is DR3
240 )))
241
242 [[image:image-20220526164650-13.png]]
243
244 (((
245 Gateway Traffic can see this downstream info
246 )))
247
248
249
250 (((
251 (% style="color:blue" %)**For LoRaWAN Gateway**
252 )))
253
254 (((
255 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:
256 )))
257
258 [[image:image-20220526164734-14.png]]
259
260 (((
261 Gateway Sent out this packet
262 )))
263
264
265
266 (((
267 (% style="color:blue" %)**For End Node**
268 )))
269
270 (((
271 we can use AT Command (AT+CFG) to check the RX1 configure and RX2 configure. as below:
272 )))
273
274 (((
275 (% style="color:#037691" %)**AT+RX2FQ=869525000**  (%%) **~-~-->**  The RX2 Window frequency
276 (% style="color:#037691" %)**AT+RX2DR=3**          (%%) **~-~-->**  The RX2 DataRate
277 (% style="color:#037691" %)**AT+RX1DL=1000**       (%%) ** ~-~-->**  Receive Delay 1
278 (% style="color:#037691" %)**AT+RX2DL=2000**       (%%) **~-~--> ** Receive Delay 2
279
280
281
282 )))
283
284 (((
285 (% style="color:blue" %)**when the device running, we can see below info:**
286 )))
287
288 {{{ [12502]***** UpLinkCounter= 0 *****
289 [12503]TX on freq 868500000 Hz at DR 0
290 [13992]txDone
291 [15022]RX on freq 868500000 Hz at DR 0 --> RX1 window open at frequency: 868500000, DR0, after 15022-13992= 1030ms of txdone
292 [15222]rxTimeOut --> no packet arrive in RX1 window. (duration: 200ms)
293 [15987]RX on freq 869525000 Hz at DR 3 --> RX2 window open at frequency: 869525000, DR3, after 15987-13992= 1995ms of txdone
294 [16027]rxTimeOut --> no packet arrive in RX2 window. (duration: 40 ms)}}}
295
296 (((
297
298
299
300 )))
301
302 (((
303 (% style="color:blue" %)**Another message:**
304 )))
305
306 {{{ [12502]***** UpLinkCounter= 0 *****
307 [12503]TX on freq 868100000 Hz at DR 0
308 [13992]txDone
309 [15022]RX on freq 868100000 Hz at DR 0
310 [15222]rxTimeOut
311 [15987]RX on freq 869525000 Hz at DR 3
312 [16185]rxDone --> We have got the downstream packet.
313 Rssi= -64
314 Receive data
315 1:0012345678}}}
316
317
318
319 == 5.3 If problem doesn't solve ==
320
321
322 (% 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:**
323
324 * End node console to show the transmit freuqency and DR.
325 * Gateway (from gateway UI) traffic to show the packet got from end node and receive from Server.
326 * Gateway traffic (from server UI) to shows the data exchange between gateway and server.
327 * End Node traffic (from server UI) to shows end node activity in server.
328
329
330
331 = 6. Downlink Issue ~-~- Packet REJECTED, unsupported frequency =
332
333
334 (((
335 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.
336 )))
337
338 (((
339
340 )))
341
342 (((
343 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:
344 )))
345
346 {{{Sat Nov 21 08:04:17 2020 daemon.info lora_pkt_fwd[1680]: ERROR~ Packet REJECTED, unsupported frequency - 923200000 (min:865000000,max:867000000)}}}
347
348 (((
349
350 )))
351
352 (((
353 In this case, please double check the gateway frequency and the server frequency band.
354 )))
355
356
357
358 = 7. Decrypt a LoRaWAN Packet =
359
360
361 (% style="color:blue" %)**1. LHT65 End device configure:**
362
363 **Change to ABP Mode:  AT+NJM=0**
364 **Change to fix frequency:  AT+CHS=904900000**
365 **Change to fix DR:  AT+DR=0**
366
367
368 [[image:image-20220526165525-16.png]]
369
370
371
372 (% style="color:blue" %)**2. In LG02 , configure to receive above message**
373
374 [[image:image-20220526165612-17.png]]
375
376
377 In LG02 console, we can see the hex receive are:
378
379 [[image:image-20220526171112-21.png]]
380
381
382
383 (% style="color:blue" %)**3. Decode the info in web**
384
385 [[https:~~/~~/lorawan-packet-decoder-0ta6puiniaut.runkit.sh>>url:https://lorawan-packet-decoder-0ta6puiniaut.runkit.sh/]]
386
387 Need these three fields:
388
389 LoRa packet hex format: 40c1190126800100024926272bf18bbb6341584e27e23245 (from LG02)
390
391 AT+NWKSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 11 (End node Network Session Key)
392
393 AT+APPSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 11 (End Node App Session Key)
394
395
396 [[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]]
397
398 [[image:image-20220526171029-20.png]]
399
400 (((
401 The FRMPayload is the device payload.
402 )))
403
404
405
406 = 8. Why i see uplink 0x00 periodcally on the LHT65 v1.8 firmware =
407
408
409 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.
410
411
412
413 = 9. Why do I see a "MIC Mismatch" error message from the server? =
414
415
416 (((
417 1)  If the user receives a "MIC Mismatch" message after registering the node on the server.
418 )))
419
420 (((
421 It is likely that the user filled in the wrong APPKEY when registering the node. Many users fill in "APPSKEY".
422 )))
423
424 * (((
425 Please note the distinction between "APPKEY" and "APPSKEY".
426 )))
427
428 (((
429 2）If the node works on the server for a period of time, the device stops working and receives a "MIC Mismatch" message.
430 )))
431
432 (((
433 The user needs a USB-TTL adapter to connect the serial port to modify the node APPKEY.
434 )))
435
436 * (((
437 If a node is registered with multiple servers, it may also cause the "mic mismatch" error.
438
439
440
441
442 )))
443
444 = 10. Why i got the payload only with "0x00" or "AA~=~="? =
445
446
447 * If you are using US915, AU915 or AS923 frequencies.It is possible because: .
448
449 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.
450
451 When the server adjusts your node rate to 0, the maximum payload length is 11 bytes. The server sometimes sends an ADR packet to the 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 an additional 00 data packet.
452
453 Solution: Use the decoder to filter out this 00 packet.
454
455 Some node decoders may not have filtering function, or you need decoders of other servers and formats. Please send an email to [[david.huang@dragino.cc>>mailto:david.huang@dragino.cc]]
456
457
458
459 = 11. Why my Dev EUI and APP EUI is 0x000000000000, how to solve? =
460
461
462 (((
463 It is possible the keys is erased during upgrading of firmware. and the console output shows below after AT+CFG
464 )))
465
466 (((
467 AT+APPKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
468 )))
469
470 (((
471 AT+NWKSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
472 )))
473
474 (((
475 AT+APPSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
476 )))
477
478 (((
479 AT+APPEUI=00 00 00 00 00 00 00 00
480 )))
481
482 (((
483
484 )))
485
486 (((
487 You can get the keys from the box sticker or send mail to Dragino Support to check keys with the provided SN number.
488 )))
489
490 (((
491 You can rewrites the keys by running commands in AT Console
492
493
494 )))
495
496 (((
497 **For example：**
498 )))
499
500 (((
501 AT+APPKEY=85 41 47 20 45 58 28 14 16 82 A0 F0 80 0D DD EE
502 )))
503
504 (((
505 AT+NWKSKEY=AA CC B0 20 30 45 37 32 14 1E 14 93 E2 3B 20 11
506 )))
507
508 (((
509 AT+APPSKEY=11 23 02 20 30 20 30 60 80 20 20 30 30 20 10 10
510 )))
511
512 (((
513 AT+APPEUI=2C 45 47 E3 24 12 23 24
514 )))
515
516 (((
517 (Any combination of 16 bit codes can be used）
518
519
520
521 = 12. I set my device is LoRaWAN Class C mode, why i still see Class A after boot? =
522 )))
523
524
525 Class C only refers to status after OTAA Join successfully. The OTAA Join Process will use Class A mode.
526
527
528
529 (% class="wikigeneratedid" %)
530