Skip to Content

Wiki source code of LoRaWAN Communication Debug

Version 32.16 by Xiaoling on 2022/08/12 11:06
Show last authors
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
21 (% style="color:blue" %)**1. End Device Join Screen shot, we can check:**
22
23 * If the device is sending join request to server?
24 * What frequency the device is sending?
25
26 [[image:image-20220526164956-15.png]]
27
28 Console Output from End device to see the transmit frequency
29
30
31
32 (% style="color:blue" %)**2. Gateway packet traffic in gateway web or ssh. we can check:**
33
34 * If the gateway receive the Join request packet from sensor? (If this fail, check if the gateway and sensor works on the match frequency)
35 * If the gateway gets the Join Accept message from server and transmit it via LoRa?
36
37 [[image:image-20220526163608-2.png]]
38
39 Console Output from Gateway to see packets between end node and server.
40
41
42 (% style="color:blue" %)**3. Gateway Traffic Page in LoRaWAN Server**
43
44 * If the Join Request packet arrive the gateway traffic in server? If not, check the internet connection and gateway LoRaWAN server settings.
45 * 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.
46 * 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.
47
48 [[image:image-20220526163633-3.png]]
49
50 The Traffic for the End node in the server, use TTN as example
51
52
53 (% style="color:blue" %)**4. Data Page in LoRaWAN server**
54
55 * 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.
56
57 [[image:image-20220526163704-4.png]]
58
59 The data for the end device set in server
60
61 [[image:image-20220526163732-5.png]]
62
63 Check if OTAA Keys match the keys in device
64
65
66
67 = 2. Notice of US915/CN470/AU915 Frequency band =
68
69
70 (((
71 If user has problem to work with lorawan server in band US915/AU915/CN470, he can check:
72 )))
73
74 * (((
75 What **sub-band** the server support ?
76 )))
77 * (((
78 What is the **sub-band** the gateway support ?
79 )))
80 * (((
81 What is the **sub-band** the end node is using ?
82 )))
83
84 (((
85 All of above should match so End Node can properly Join the server and don't have packet lost.
86 )))
87
88 (((
89
90 )))
91
92 (((
93 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.
94 )))
95
96 (((
97
98 )))
99
100 (((
101 Here are the freuqency tables for these bands as reference:
102 )))
103
104 [[image:image-20220526163801-6.png]]
105
106 US915 Channels
107
108 [[image:image-20220526163926-7.png]]
109
110 AU915 Channels
111
112
113 [[image:image-20220526163941-8.png]]
114
115 (((
116 CN470 Channels
117
118
119 )))
120
121 (((
122 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.
123 )))
124
125 [[image:image-20220526164052-9.png]]
126
127 (((
128 TTN FREQUENCY PLAN
129
130
131 )))
132
133 (((
134 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. )
135 )))
136
137
138
139 = 3. Why i see data lost/unperiocially uplink data? Even the signal strength is good =
140
141
142 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:
143
144 * **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.
145 * **Gateway** ~-~-> Use Sub-band2 (Channel 8,9,10,11,12,13,14,15) for Dragino Gateway. this is the default settings for dragino sensors.
146 * **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.
147
148 (((
149 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.
150 )))
151
152 (((
153
154 )))
155
156 (((
157 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.
158 )))
159
160
161
162 = 4. Transmision on ABP Mode =
163
164
165 (((
166 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.
167 )))
168
169 (((
170
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
179 )))
180
181 (((
182 To solve this, disable the Frame Counter Check will solve this issue , or reset the frame counter in the device page.
183 )))
184
185 [[image:image-20220526164508-10.png]]
186
187 Disable Frame Counter Check in ABP Mode
188
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 * The LoRaWAN server must send a downstream packet, and the gateway forward this downstream packet for this end node.
211 * This downstream packet must arrive to the end node while RX1 or RX2 is open.
212 * This packet must match the frequency of the RX1 or RX2 window.
213 * 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.**
214
215
216
217
218 == 5.2 See Debug Info ==
219
220
221 (((
222 (% style="color:blue" %)**For LoRaWAN Server**
223 )))
224
225 (((
226 We can check if there is downlink message for this end node, use TTN for example:
227 )))
228
229 (((
230 Configure a downstream to the end device
231 )))
232
233 [[image:image-20220526164623-12.png]]
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 include the DR which is used (SF9BW125) in EU868 is DR3
242 )))
243
244 [[image:image-20220526164650-13.png]]
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 (% style="color:#037691" %)**AT+RX2DR=3**          (%%) **~-~-->**  The RX2 DataRate
279 (% style="color:#037691" %)**AT+RX1DL=1000**       (%%) ** ~-~-->**  Receive Delay 1
280 (% style="color:#037691" %)**AT+RX2DL=2000**       (%%) **~-~--> ** Receive Delay 2
281
282
283
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
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 * Gateway (from gateway UI) traffic to show the packet got from end node and receive from Server.
328 * Gateway traffic (from server UI) to shows the data exchange between gateway and server.
329 * End Node traffic (from server UI) to shows end node activity in server.
330
331
332
333
334 = 6. Downlink Issue ~-~- Packet REJECTED, unsupported frequency =
335
336
337 (((
338 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.
339 )))
340
341 (((
342
343 )))
344
345 (((
346 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:
347 )))
348
349 {{{Sat Nov 21 08:04:17 2020 daemon.info lora_pkt_fwd[1680]: ERROR~ Packet REJECTED, unsupported frequency - 923200000 (min:865000000,max:867000000)}}}
350
351 (((
352
353 )))
354
355 (((
356 In this case, please double check the gateway frequency and the server frequency band.
357 )))
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 **Change to fix frequency:  AT+CHS=904900000**
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
409 = 8. Why i see uplink 0x00 periodcally on the LHT65 v1.8 firmware =
410
411
412 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.
413
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
444
445 )))
446
447 = 10. Why i got the payload only with "0x00" or "AA~=~="? =
448
449
450 * If you are using US915, AU915 and AS923 frequencies.This is normal phenomenon.
451
452 (((
453 When using the frequency mentioned above, the server sometimes adjusts the rate of the node, because the node defaults to the adaptive rate.
454 )))
455
456 (((
457 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.
458 )))
459
460 * (((
461 Solution: Use the decoder to filter out this 00 packet.
462 )))
463 * (((
464 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]]
465
466
467
468
469 )))
470
471 = 11. Why my Dev EUI and APP EUI is 0x000000000000, how to solve? =
472
473
474 (((
475 It is possible the keys is erased during upgrading of firmware. and the console output shows below after AT+CFG
476 )))
477
478 (((
479 AT+APPKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
480 )))
481
482 (((
483 AT+NWKSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
484 )))
485
486 (((
487 AT+APPSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
488 )))
489
490 (((
491 AT+APPEUI=00 00 00 00 00 00 00 00
492 )))
493
494 (((
495
496 )))
497
498 (((
499 You can get the keys from the box sticker or send mail to Dragino Support to check keys with the provided SN number.
500 )))
501
502 (((
503 You can rewrites the keys by running commands in AT Console
504
505
506 )))
507
508 (((
509 **For example：**
510 )))
511
512 (((
513 AT+APPKEY=85 41 47 20 45 58 28 14 16 82 A0 F0 80 0D DD EE
514 )))
515
516 (((
517 AT+NWKSKEY=AA CC B0 20 30 45 37 32 14 1E 14 93 E2 3B 20 11
518 )))
519
520 (((
521 AT+APPSKEY=11 23 02 20 30 20 30 60 80 20 20 30 30 20 10 10
522 )))
523
524 (((
525 AT+APPEUI=2C 45 47 E3 24 12 23 24
526 )))
527
528 (((
529 (Any combination of 16 bit codes can be used）
530
531
532
533 = 12. I set my device is LoRaWAN Class C mode, why i still see Class A after boot? =
534 )))
535
536
537 Class C only refers to status after OTAA Join successfully. The OTAA Join Process will use Class A mode.
538
539
540
541 (% class="wikigeneratedid" %)
542