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Wiki source code of LoRaWAN Communication Debug

Last modified by Xiaoling on 2025/05/05 08:51
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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 [[image:image-20240129142631-4.png||height="637" width="1256"]]
67
68 Check if OTAA Keys match the keys in device.
69
70
71 = 2. Notice of US915/CN470/AU915 Frequency band =
72
73
74 (((
75 If user has problem to work with LoRaWAN server in band US915/AU915/CN470, he can check:
76 )))
77
78 * (((
79 What **sub-band** the server support?
80 )))
81 * (((
82 What is the **sub-band** the gateway support?
83 )))
84 * (((
85 What is the **sub-band** the end node is using?
86 )))
87
88 (((
89 All of above should match so End Node can properly Join the server and don't have packet lost.
90 )))
91
92 (((
93
94 )))
95
96 (((
97 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.
98 )))
99
100 (((
101
102 )))
103
104 (((
105 Here are the frequency tables for these bands as reference:
106 )))
107
108 [[image:image-20220526163801-6.png]]
109
110 US915 Channels
111
112
113 [[image:image-20220526163926-7.png]]
114
115 AU915 Channels
116
117
118 [[image:image-20220526163941-8.png]]
119
120 (((
121 CN470 Channels
122
123
124 )))
125
126 (((
127 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.
128 )))
129
130 [[image:image-20240123151225-3.png||height="434" width="902"]]
131
132 (((
133 TTN FREQUENCY PLAN
134
135 (% style="display:none" %) (%%)
136 )))
137
138 (((
139 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. )
140 )))
141
142 (% style="display:none" %) (%%)
143
144 = 3. Why I see data lost/ is not periodically uplink？ Even the signal strength is good =
145
146
147 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:
148
149 * (% 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.
150
151 * (% 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.
152
153 * (% 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.
154
155 (((
156 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.
157 )))
158
159
160 (((
161 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.
162 )))
163
164
165 = 4. Why i see packet lost =
166
167 == **1. Signal problem** ==
168
169
170 (% style="color:blue" %)**1)**(%%)  (% style="color:blue" %)**ADR automatic adjustment** (%%)
171
172 **Reason:**
173
174 When the signal is at a critical value, the server may configure the node to adjust to a lower power DR.
175 At this time, the server is at risk of losing uplink.
176
177
178 **Solution:**
179
180 Users can manually fix the DR value.
181
182
183 (% style="color:red" %)
184 **Notice:**
185
186 * User need to set Adaptive Data Rate(ADR)=0 first. otherwise device will respond to server's ADR command and change the DR according to server auto-adjustment.
187
188 * Data Rate specifies Spreading Factor. The mapping varies in different frequency bands. User can check this link for detail. [[rp2-1.0.3-lorawan-regional-parameters.pdf>>https://lora-alliance.org/resource_hub/rp2-1-0-3-lorawan-regional-parameters/]]
189
190 (% style="color:blue" %)**AT Command: AT+DR**
191
192 (% border="1" cellspacing="4" style="background-color:#f2f2f2; width:409px" %)
193 |(% style="background-color:#4f81bd; color:white; width:156px" %)**Command Example**|(% style="background-color:#4f81bd; color:white; width:147px" %)**Function**|(% style="background-color:#4f81bd; color:white; width:100px" %)**Response**
194 |(% style="width:156px" %)AT+DR=?|(% style="width:147px" %)Get the Data Rate.|(% style="width:100px" %)5(((
195 OK
196 )))
197 |(% style="width:156px" %)AT+DR=2|(% style="width:147px" %)Set the Data Rate.|(% style="width:100px" %)OK(((
198
199 )))
200
201 (% style="color:blue" %)**Downlink Command: 0x2200aaFF**
202
203 If the downlink payload=220001FF, it means setting the data rate to 1, while type code is 22 00 aa FF.
204
205 * **Example 1**: Downlink Payload: **220001FF**  ~/~/ Set AT+DR=1.
206
207 * **Example 2**: Downlink Payload: **220000FF**  ~/~/ Set AT+DR=0.
208
209 (% style="display:none" %) (%%)
210
211
212 (% style="color:blue" %)**2)**(%%)  (% style="color:blue" %)**Node antenna problem**
213
214 **Reason:**
215
216 Node antenna is loose
217
218
219 **Solution:**
220
221 Please check whether the antenna interface and module interface are detached
222
223 [[image:image-20250429114526-1.png||height="429" width="303"]]
224
225
226
227 (% style="color:blue" %)**3) **(%%) (% style="color:blue" %)**Gateway antenna problem**
228
229 **Reason:**
230 Gateway uses antenna with wrong frequency band
231
232 For example: 868-band gateway uses antenna with 915-band, which will cause the signal to be greatly reduced
233
234
235 **Solution:**
236
237 Please check whether the silk screen on the antenna conflicts with the frequency you set.
238
239 [[image:image-20250429115124-2.png]][[image:image-20250429115159-3.png||height="550" width="224"]]
240
241
242 (% style="color:blue" %)**4) **(%%) (% style="color:blue" %)**Gateway module problem**
243
244 **Reason:**
245
246 Gateway uses module with wrong frequency band
247 For example: 868-band gateway uses module with 915-band, which will cause the signal to be greatly reduced
248
249
250 **Solution:**
251
252 Please check whether the silkscreen of the module conflicts with the frequency you set.
253
254 [[image:image-20250429115951-5.png||height="288" width="384"]][[image:image-20250429133640-7.png||height="284" width="378"]]
255
256
257 == **2. Frequency point problem** ==
258
259
260 **Reason:**
261
262 There are multiple frequency configurations in AS923/US915/AU915/CN470.
263
264 The frequency point of the gateway or server is wrong or missing.
265
266
267 **Solution:**
268
269 Users need to check whether the server or gateway configuration is missing or has an incorrect frequency.
270
271 The frequency range used in the dragino node is as follows
272
273
274 == **3. Frequency band problem** ==
275
276
277 **Reason:**
278
279 When there are multiple gateways, the node cannot lock the frequency band.
280
281
282 **Solution:**
283
284 (((
285 By default, the frequency bands US915, AU915, CN470 work in 72 frequencies. Many gateways are 8 channel gateways, and in this case, the OTAA join time and uplink schedule is long and unpredictable while the end node is hopping in 72 frequencies.
286 )))
287
288 (((
289 You can configure the end node to work in 8 channel mode by using the AT+CHE command. The 500kHz channels are always included for OTAA.
290 )))
291
292 (((
293
294 )))
295
296 (((
297 For example, in (% style="color:blue" %)**US915**(%%) band, the frequency table is as below. By default, the end node will use all channels (0~~71) for OTAA Join process. After the OTAA Join, the end node will use these all channels (0~~71) to send uplink packets.
298 )))
299
300 [[image:https://wiki.dragino.com/xwiki/bin/download/Main/User%20Manual%20for%20LoRaWAN%20End%20Nodes/LSN50%20%26%20LSN50-V2%20-%20LoRaWAN%20Sensor%20Node%20User%20Manual/WebHome/image-20220627160940-13.png?rev=1.1||alt="image-20220627160940-13.png"]]
301
302
303 (((
304 When you use the TTN V3 network, the US915 frequency bands use are:
305 )))
306
307 * (((
308 903.9 - SF7BW125 to SF10BW125
309 )))
310 * (((
311 904.1 - SF7BW125 to SF10BW125
312 )))
313 * (((
314 904.3 - SF7BW125 to SF10BW125
315 )))
316 * (((
317 904.5 - SF7BW125 to SF10BW125
318 )))
319 * (((
320 904.7 - SF7BW125 to SF10BW125
321 )))
322 * (((
323 904.9 - SF7BW125 to SF10BW125
324 )))
325 * (((
326 905.1 - SF7BW125 to SF10BW125
327 )))
328 * (((
329 905.3 - SF7BW125 to SF10BW125
330 )))
331 * (((
332 904.6 - SF8BW500
333 )))
334
335 (((
336 Because the end node is now hopping in 72 frequency, it makes it difficult for the devices to Join the TTN V3 network and uplink data. To solve this issue, you can access the device via the AT commands and run:
337 )))
338
339 (((
340 (% style="color:blue" %)**AT+CHE=2**
341 )))
342
343 (((
344 (% style="color:blue" %)**ATZ**
345 )))
346
347
348 (((
349 to set the end node to work in 8 channel mode. The device will work in Channel 8-15 & 64-71 for OTAA, and channel 8-15 for Uplink.
350 )))
351
352 (((
353 The (% style="color:blue" %)**AU915**(%%) band is similar. Below are the AU915 Uplink Channels.
354
355 [[image:https://wiki.dragino.com/xwiki/bin/download/Main/User%20Manual%20for%20LoRaWAN%20End%20Nodes/LSN50%20%26%20LSN50-V2%20-%20LoRaWAN%20Sensor%20Node%20User%20Manual/WebHome/image-20220627161124-14.png?rev=1.1||alt="image-20220627161124-14.png"]]
356
357
358 )))
359
360 = 5. Transmision on ABP Mode =
361
362
363 (((
364 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.
365 )))
366
367 (((
368 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.
369 )))
370
371 (((
372 To solve this, disable the Frame Counter Check will solve this issue , or reset the frame counter in the device page.
373
374 [[image:image-20240123161737-4.png||height="395" width="763"]]
375 )))
376
377 [[image:image-20240123161853-6.png||height="599" width="771"]]
378
379 Disable Frame Counter Check in ABP Mode
380
381
382 = 6. Downstream Debug =
383
384 == 6.1 How it work ==
385
386
387 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.
388
389 (((
390 Depends on Class A or Class C, the receive windows will be a little difference. The main difference between Class A and Class C:
391
392 * **Class A** : Suitable for Battery powered end node. Class A will save a lot of power but it can only receive downlink after each uplink
393 * **Class C**: End node can receive downlink immediately but have higher power consumption.
394
395
396 )))
397
398 [[image:image-20220531161828-1.png]]
399
400 receive windows for Class A and Class C
401
402
403 Below are the requirement for the End Device to receive the packets.
404
405 * The End Device must open the receive windows: RX1 or RX2
406
407 * The LoRaWAN server must send a downstream packet, and the gateway forward this downstream packet for this end node.
408
409 * This downstream packet must arrive to the end node while RX1 or RX2 is open.
410
411 * This packet must match the frequency of the RX1 or RX2 window.
412
413 * 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.**
414
415 == 6.2 See Debug Info ==
416
417
418 (((
419 (% style="color:blue" %)**For LoRaWAN Server**
420 )))
421
422 (((
423 We can check if there is downlink message for this end node, use TTN for example:
424 )))
425
426 (((
427 Configure a downlink to the end device
428
429 [[image:image-20240129152412-8.png||height="486" width="1206"]]
430 )))
431
432
433 (((
434 Set a downstream in TTN and see it is sent
435 )))
436
437 (% style="color:red" %)**Note: After the downlink command is successfully sent from the platform to the node, the downlink command is executed only after the platform receives the next uplink package from the node.**
438
439
440 (((
441 This downlink info will then pass to the gateway downlink list. and the DR which is used (SF7BW500) in US915 is DR5.
442 )))
443
444 [[image:image-20240129152049-7.png||height="463" width="1166"]]
445
446 (((
447 Gateway Traffic can see this downlink info
448 )))
449
450
451
452 (((
453 (% style="color:blue" %)**For LoRaWAN Gateway**
454 )))
455
456 (((
457 When the downlink packet appear on the traffic of Gateway page. The LoRaWAN gateway can get it from LoRaWAN server and transmit it. In Dragino Gateway, this can be checked by running "logread -f" in the SSH console. and see below:
458 )))
459
460 [[image:image-20240129154321-9.png]]
461
462 (((
463 Gateway Sent out this packet
464 )))
465
466
467
468 (((
469 (% style="color:blue" %)**For End Node**
470 )))
471
472 (((
473 we can use AT Command (AT+CFG) to check the RX1 configure and RX2 configure. as below:
474 )))
475
476 (((
477 * (% style="color:#037691" %)**AT+RX2FQ=869525000**  (%%) **~-~-->**  The RX2 Window frequency
478
479 * (% style="color:#037691" %)**AT+RX2DR=3**          (%%) **~-~-->**  The RX2 DataRate
480
481 * (% style="color:#037691" %)**AT+RX1DL=1000**       (%%) ** ~-~-->**  Receive Delay 1
482
483 * (% style="color:#037691" %)**AT+RX2DL=2000**       (%%) **~-~--> ** Receive Delay 2
484 )))
485
486 (((
487 (% style="color:blue" %)**when the device running, we can see below info:**
488 )))
489
490 {{{ [12502]***** UpLinkCounter= 0 *****
491 [12503]TX on freq 868500000 Hz at DR 0
492 [13992]txDone
493 [15022]RX on freq 868500000 Hz at DR 0 --> RX1 window open at frequency: 868500000, DR0, after 15022-13992= 1030ms of txdone
494 [15222]rxTimeOut --> no packet arrive in RX1 window. (duration: 200ms)
495 [15987]RX on freq 869525000 Hz at DR 3 --> RX2 window open at frequency: 869525000, DR3, after 15987-13992= 1995ms of txdone
496 [16027]rxTimeOut --> no packet arrive in RX2 window. (duration: 40 ms)}}}
497
498 (((
499
500
501
502 )))
503
504 (((
505 (% style="color:blue" %)**Another message:**
506 )))
507
508 {{{ [12502]***** UpLinkCounter= 0 *****
509 [12503]TX on freq 868100000 Hz at DR 0
510 [13992]txDone
511 [15022]RX on freq 868100000 Hz at DR 0
512 [15222]rxTimeOut
513 [15987]RX on freq 869525000 Hz at DR 3
514 [16185]rxDone --> We have got the downstream packet.
515 Rssi= -64
516 Receive data
517 1:0012345678}}}
518
519
520 == 6.3 If problem doesn't solve ==
521
522
523 (% 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:**
524
525 * End node console to show the transmit freuqency and DR.
526
527 * Gateway (from gateway UI) traffic to show the packet got from end node and receive from Server.
528
529 * Gateway traffic (from server UI) to shows the data exchange between gateway and server.
530
531 * End Node traffic (from server UI) to shows end node activity in server.
532
533 = 7. Downlink Issue ~-~- Packet REJECTED, unsupported frequency =
534
535
536 (((
537 In LoRaWAN, the gateway 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.
538 )))
539
540 (((
541
542 )))
543
544 (((
545 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:
546 )))
547
548 {{{Sat Nov 21 08:04:17 2020 daemon.info lora_pkt_fwd[1680]: ERROR~ Packet REJECTED, unsupported frequency - 923200000 (min:865000000,max:867000000)}}}
549
550 (((
551
552 )))
553
554 (((
555 In this case, please double check the gateway frequency and the server frequency band.
556 )))
557
558
559 = 8. Decrypt a LoRaWAN Packet =
560
561
562 (% style="color:blue" %)**1. LHT65N End device configure:**
563
564 **Change to ABP Mode:  AT+NJM=0**
565
566 **Change to fix frequency:  ​​​​AT+CHE=1**
567
568
569 **AT+CFG(Print configuration):**
570
571 [[image:image-20240129170603-7.png||height="697" width="545"]][[image:image-20240129163741-3.png||height="694" width="565"]]
572
573
574 **Configuration: **
575
576 [[image:image-20240129164219-4.png||height="612" width="440"]]
577
578
579
580 (% style="color:blue" %)**2. In LPS8-v2, configure to receive above message**
581
582 [[image:image-20240129164326-5.png||height="506" width="1114"]]
583
584
585 In LPS8-v2 console, we can see the Base64 receive are:
586
587 [[image:image-20240129170137-6.png||height="459" width="1116"]]
588
589
590 (% style="color:blue" %)**3. Decode the info in CMD(Command prompt window)**
591
592 LoRa packet Base64 format:  QP~/~/~/~/+AFQACZv8Hjmc8gFTAkhMzU+75 **(from LPS8-v2)**
593
594 Then the instructions and format parsed in SecureCRT are:  ./node_modules/.bin/lora-packet-decode ~-~-base64 QP~/~/~/~/+AFQACZv8Hjmc8gFTAkhMzU+75
595
596
597 **Step1: Open CMD, Enter the gateway IP and port.(ssh root@gateway IP -p 22)**
598
599 [[image:image-20240129190752-17.png||height="338" width="901"]]
600
601 [[image:image-20240129191937-21.png||height="450" width="901"]]
602
603
604 **Step2: Enter the command to download the LoRa parsing package.(npm install lora-packet)**
605
606 [[image:image-20240129192239-22.png||height="416" width="902"]]
607
608 [[image:image-20240129192549-23.png||height="459" width="898"]]
609
610
611 **Step3: Parse the gateway raw payload.(./node_modules/.bin/lora-packet-decode ~-~-base64 QP~/~/~/~/+AFQACZv8Hjmc8gFTAkhMzU+75)**
612
613 [[image:image-20240129192908-24.png||height="477" width="907"]]
614
615 [[image:image-20240129192954-25.png||height="485" width="916"]]
616
617
618 = 9. Why I see uplink 0x00 periodically on the LHT65 v1.8 firmware =
619
620
621 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.
622
623
624 = 10. Why do I see a "MIC Mismatch" error message from the server? =
625
626
627 (((
628 1)  If the user receives a "MIC Mismatch" message after registering the node on the server.
629 )))
630
631 (((
632 It is likely that the user filled in the wrong APPKEY when registering the node. Many users fill in "APPSKEY".
633 )))
634
635 * (((
636 Please note the distinction between "APPKEY" and "APPSKEY".
637 )))
638
639 (((
640 2）If the node works on the server for a period of time, the device stops working and receives a "MIC Mismatch" message.
641 )))
642
643 (((
644 The user needs a USB-TTL adapter to connect the serial port to modify the node APPKEY.
645 )))
646
647 * (((
648 If a node is registered with multiple servers, it may also cause the "mic mismatch" error.
649 )))
650
651 (% class="wikigeneratedid" %)
652 3）Wrong Regional Parameters version selected
653 We generally use versions above 1.0.2
654
655 (% class="wikigeneratedid" %)
656 [[image:image-20230322163227-1.png]]
657
658 (% class="wikigeneratedid" %)
659 4）We have had cases where it was automatically fixed the next day despite no manual changes, probably a server side issue
660
661
662 = 11. Why I got the payload only with "0x00" or "AA~=~="? =
663
664
665 (% style="color:blue" %)**Why sensor sends 0x00?**
666
667 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.
668
669 **Possible Case 1**:
670
671 Sensor has ADR=1 enable and sensor need to reply server MAC command (ADR request) while sensor has DR=0.
672
673
674 **Possible Case 2:**
675
676 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.
677
678
679 (% style="color:blue" %)**How to solve:**
680
681 Solution:
682
683 ~1. Use the decoder to filter out this 0x00 packet. (**Recommand**)
684
685 2. Data rate changed from DR3 to DR5, increasing upload byte length
686 AT+ADR=0
687 AT+DR=3
688
689 Downlink：
690
691 [[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]]
692
693 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]]
694
695
696 = 12. Why my Dev EUI and APP EUI is 0x000000000000, how to solve? =
697
698
699 (((
700 It is possible the keys is erased during upgrading of firmware. and the console output shows below after AT+CFG
701 )))
702
703 (((
704 AT+APPKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
705 )))
706
707 (((
708 AT+NWKSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
709 )))
710
711 (((
712 AT+APPSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
713 )))
714
715 (((
716 AT+APPEUI=00 00 00 00 00 00 00 00
717 )))
718
719 (((
720
721 )))
722
723 (((
724 You can get the keys from the box sticker or send mail to Dragino Support to check keys with the provided SN number.
725 )))
726
727 (((
728 You can rewrites the keys by running commands in AT Console
729
730
731 )))
732
733 (((
734 **For example：**
735 )))
736
737 (((
738 AT+APPKEY=85 41 47 20 45 58 28 14 16 82 A0 F0 80 0D DD EE
739 )))
740
741 (((
742 AT+NWKSKEY=AA CC B0 20 30 45 37 32 14 1E 14 93 E2 3B 20 11
743 )))
744
745 (((
746 AT+APPSKEY=11 23 02 20 30 20 30 60 80 20 20 30 30 20 10 10
747 )))
748
749 (((
750 AT+APPEUI=2C 45 47 E3 24 12 23 24
751 )))
752
753 (((
754 (Any combination of 16 bit codes can be used）
755
756
757 = 13. I set my device is LoRaWAN Class C mode, why I still see Class A after boot? =
758 )))
759
760
761 Class C only refers to status after OTAA Join successfully. The OTAA Join Process will use Class A mode.
762
763
764 = 14. Why it takes longer time for OTAA joined in US915/CN470/AU915 band? =
765
766
767 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.
768
769
770 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:
771
772 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:
773
774 * (((
775 Check what sub-band the LoRaWAN server ask from the OTAA Join Accept message and switch to that sub-band.
776 )))
777 * (((
778 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).
779 )))
780
781 This change will make the activation time a little longer but make sure the device can be used in any sub-band.
782
783
784 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.
785
786
787 [[image:image-20221215223215-1.png||height="584" width="1280"]]