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Wiki source code of LoRaWAN Communication Debug

Version 4.9 by Xiaoling on 2022/05/11 15:20
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1 **~ Contents:**
2
3 {{toc/}}
4
5
6 = 1. OTAA Join Process Debug =
7
8 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.
9 \\**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:**
10
11 * End node console to show the Join freuqency and DR. (If possible)
12 * Gateway (from gateway UI) traffic to show the packet got from end node and receive from Server. (If possible)
13 * Gateway traffic (from server UI) to shows the data exchange between gateway and server. (Normaly possible)
14 * End Node traffic (from server UI) to shows end node activity in server. (Normaly possible)
15 * 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)
16
17 **~1. End Device Join Screen shot, we can check:**
18
19 * If the device is sending join request to server?
20 * What frequency the device is sending?
21
22 [[image:https://wiki.dragino.com/images/thumb/0/0f/OTAA_Join-1.jpg/600px-OTAA_Join-1.jpg||height="316" width="600"]]
23
24 Console Output from End device to see the transmit frequency
25
26
27 **2. Gateway packet traffic in gateway web or ssh. we can check:**
28
29 * If the gateway receive the Join request packet from sensor? (If this fail, check if the gateway and sensor works on the match frequency)
30 * If the gateway gets the Join Accept message from server and transmit it via LoRa?
31
32 [[image:https://wiki.dragino.com/images/thumb/1/1c/OTAA_Join-2.png/600px-OTAA_Join-2.png||height="325" width="600"]]
33
34 Console Output from Gateway to see packets between end node and server.
35
36
37 **3. Gateway Traffic Page in LoRaWAN Server**
38
39 * If the Join Request packet arrive the gateway traffic in server? If not, check the internet connection and gateway LoRaWAN server settings.
40 * 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.
41 * 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.
42
43 [[image:https://wiki.dragino.com/images/thumb/5/5c/OTAA_Join-3.png/600px-OTAA_Join-3.png||height="301" width="600"]]
44
45 The Traffic for the End node in the server, use TTN as example
46
47
48 **4. Data Page in LoRaWAN server**
49
50 * 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.
51
52 [[image:https://wiki.dragino.com/images/thumb/e/ec/OTAA_Join-4.png/600px-OTAA_Join-4.png||height="181" width="600"]]
53
54 The data for the end device set in server
55
56 [[image:https://wiki.dragino.com/images/thumb/b/b1/OTAA_Join-5.png/600px-OTAA_Join-5.png||height="166" width="600"]]
57
58 Check if OTAA Keys match the keys in device
59
60
61 = 2. Notice of US915/CN470/AU915 Frequency band =
62
63 (((
64 If user has problem to work with lorawan server in band US915/AU915/CN470, he can check:
65 )))
66
67 * (((
68 What **sub-band** the server support ?
69 )))
70 * (((
71 What is the **sub-band** the gateway support ?
72 )))
73 * (((
74 What is the **sub-band** the end node is using ?
75 )))
76
77 (((
78 All of above should match so End Node can properly Join the server and don't have packet lost.
79 )))
80
81 (((
82
83 )))
84
85 (((
86 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.
87 )))
88
89 (((
90
91 )))
92
93 (((
94 Here are the freuqency tables for these bands as reference:
95 )))
96
97 [[image:https://wiki.dragino.com/images/thumb/3/3f/US915_FRE_BAND-1.png/600px-US915_FRE_BAND-1.png||height="170" width="600"]]
98
99 US915 Channels
100
101 [[image:https://wiki.dragino.com/images/thumb/8/8a/AU915_FRE_BAND-1.png/600px-AU915_FRE_BAND-1.png||height="167" width="600"]]
102
103 AU915 Channels
104
105 [[image:https://wiki.dragino.com/images/thumb/3/3a/CN470_FRE_BAND-1.png/600px-CN470_FRE_BAND-1.png||height="205" width="600"]]
106
107 (((
108 CN470 Channels
109 )))
110
111 (((
112 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.
113 )))
114
115 [[image:https://wiki.dragino.com/images/thumb/9/9a/US915_FRE_BAND-2.png/600px-US915_FRE_BAND-2.png||height="288" width="600"]]
116
117 (((
118 TTN FREQUENCY PLAN
119 )))
120
121 (((
122 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. )
123 )))
124
125
126 = 3. Why i see data lost/unperiocially uplink data? Even the signal strength is good =
127
128 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:
129
130 * **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.
131 * **Gateway** ~-~-> Use Sub-band2 (Channel 8,9,10,11,12,13,14,15) for Dragino Gateway. this is the default settings for dragino sensors.
132 * **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.
133
134 (((
135 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.
136 )))
137
138 (((
139
140 )))
141
142 (((
143 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.
144 )))
145
146
147 = 4. Transmision on ABP Mode =
148
149 (((
150 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.
151 )))
152
153 (((
154
155 )))
156
157 (((
158 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.
159 )))
160
161 (((
162
163 )))
164
165 (((
166 To solve this, disable the Frame Counter Check will solve this issue , or reset the frame counter in the device page.
167 )))
168
169 [[~[~[image:https://wiki.dragino.com/images/thumb/1/19/ABP_Issue-1.jpg/600px-ABP_Issue-1.jpg~|~|height="340" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:ABP_Issue-1.jpg]]
170
171 Disable Frame Counter Check in ABP Mode
172
173
174 = 5. Downstream Debug =
175
176 == 5.1 How it work ==
177
178 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.
179
180 (((
181 Depends on Class A or Class C, the receive windows will be a little difference,
182 )))
183
184 [[image:https://wiki.dragino.com/images/thumb/1/1a/Downstream_LoRaWAN-1.png/600px-Downstream_LoRaWAN-1.png||height="590" width="600"]]
185
186 receive windows for Class A and Class C
187
188 Below are the requirement for the End Device to receive the packets.
189
190 * The End Device must open the receive windows: RX1 or RX2
191 * The LoRaWAN server must send a downstream packet, and the gateway forward this downstream packet for this end node.
192 * This downstream packet must arrive to the end node while RX1 or RX2 is open.
193 * This packet must match the frequency of the RX1 or RX2 window.
194 * This packet must match the DataRate of RX1(RX1DR) or RX2 (RX2DR). **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.**
195
196 == 5.2 See Debug Info ==
197
198 (((
199 **For LoRaWAN Server**
200 )))
201
202 (((
203 We can check if there is downlink message for this end node, use TTN for example:
204 )))
205
206 (((
207 Configure a downstream to the end device
208 )))
209
210 [[image:https://wiki.dragino.com/images/thumb/8/82/Downstream_debug_1.png/600px-Downstream_debug_1.png||height="217" width="600"]]
211
212 (((
213 Set a downstream in TTN and see it is sent
214 )))
215
216
217 (((
218 This downstream info will then pass to the gateway downstream list. and include the DR which is used (SF9BW125) in EU868 is DR3
219 )))
220
221 [[image:https://wiki.dragino.com/images/thumb/d/dc/Downstream_debug_2.png/600px-Downstream_debug_2.png||height="245" width="600"]]
222
223 (((
224 Gateway Traffic can see this downstream info
225 )))
226
227
228 (((
229 **For LoRaWAN Gateway**
230 )))
231
232 (((
233 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:
234 )))
235
236 [[image:https://wiki.dragino.com/images/thumb/2/21/Downstream_debug_3.png/600px-Downstream_debug_3.png||height="195" width="600"]]
237
238 (((
239 Gateway Sent out this packet
240 )))
241
242
243 (((
244 **For End Node**
245 )))
246
247 (((
248 we can use AT Command (AT+CFG) to check the RX1 configure and RX2 configure. as below:
249 )))
250
251 (((
252
253 )))
254
255 (((
256 (% class="box infomessage" %)
257 (((
258 AT+RX2FQ=869525000     ~-~--> The RX2 Window frequency
259 AT+RX2DR=3      ~-~--> The RX2 DataRate
260 AT+RX1DL=1000   ~-~--> Receive Delay 1
261 AT+RX2DL=2000   ~-~--> Receive Delay 2
262 )))
263 )))
264
265 (% class="box infomessage" %)
266 (((
267 AT+RX2DR=3 ~-~--> The RX2 DataRate
268 )))
269
270 (% class="box infomessage" %)
271 (((
272 AT+RX1DL=1000 ~-~--> Receive Delay 1
273 )))
274
275 (% class="box infomessage" %)
276 (((
277 AT+RX2DL=2000 ~-~--> Receive Delay 2
278 )))
279
280 (((
281 **when the device running, we can see below info:**
282 )))
283
284 {{{ [12502]***** UpLinkCounter= 0 *****
285 [12503]TX on freq 868500000 Hz at DR 0
286 [13992]txDone
287 [15022]RX on freq 868500000 Hz at DR 0 --> RX1 window open at frequency: 868500000, DR0, after 15022-13992= 1030ms of txdone
288 [15222]rxTimeOut --> no packet arrive in RX1 window. (duration: 200ms)
289 [15987]RX on freq 869525000 Hz at DR 3 --> RX2 window open at frequency: 869525000, DR3, after 15987-13992= 1995ms of txdone
290 [16027]rxTimeOut --> no packet arrive in RX2 window. (duration: 40 ms)}}}
291
292 (((
293
294 )))
295
296 (((
297 **Another message:**
298 )))
299
300 {{{ [12502]***** UpLinkCounter= 0 *****
301 [12503]TX on freq 868100000 Hz at DR 0
302 [13992]txDone
303 [15022]RX on freq 868100000 Hz at DR 0
304 [15222]rxTimeOut
305 [15987]RX on freq 869525000 Hz at DR 3
306 [16185]rxDone --> We have got the downstream packet.
307 Rssi= -64
308 Receive data
309 1:0012345678}}}
310
311 == 5.3 If problem doesn’t solve ==
312
313 **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:**
314
315 * End node console to show the transmit freuqency and DR.
316 * Gateway (from gateway UI) traffic to show the packet got from end node and receive from Server.
317 * Gateway traffic (from server UI) to shows the data exchange between gateway and server.
318 * End Node traffic (from server UI) to shows end node activity in server.
319
320 = 6. Downlink Issue ~-~- Packet REJECTED, unsupported frequency =
321
322 (((
323 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.
324 )))
325
326 (((
327
328 )))
329
330 (((
331 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:
332 )))
333
334 {{{Sat Nov 21 08:04:17 2020 daemon.info lora_pkt_fwd[1680]: ERROR~ Packet REJECTED, unsupported frequency - 923200000 (min:865000000,max:867000000)}}}
335
336 (((
337
338 )))
339
340 (((
341 In this case, please double check the gateway frequency and the server frequency band.
342 )))
343
344
345 = 7. Decrypt a LoRaWAN Packet =
346
347 ~1. LHT65 End device configure:
348
349 (% class="box infomessage" %)
350 (((
351 Change to ABP Mode: AT+NJM=0
352 )))
353
354 (% class="box infomessage" %)
355 (((
356 Change to fix frequency: AT+CHS=904900000
357 )))
358
359 (% class="box infomessage" %)
360 (((
361 Change to fix DR: AT+DR=0
362 )))
363
364 [[image:https://wiki.dragino.com/images/e/e6/Decrypt_a_LoRaWAN_Packet1.jpg||alt="Decrypt a LoRaWAN Packet1.jpg" height="607" width="558"]]
365
366 2. In LG02 , configure to receive above message
367
368 [[image:https://wiki.dragino.com/images/c/c3/Decrypt_a_LoRaWAN_Packet2.jpg||alt="Decrypt a LoRaWAN Packet2.jpg" height="337" width="558"]]
369
370 In LG02 console, we can see the hex receive are:
371
372 [[image:https://wiki.dragino.com/images/f/f1/Decrypt_a_LoRaWAN_Packet3.jpg||alt="Decrypt a LoRaWAN Packet3.jpg" height="179" width="558"]]
373
374 3. Decode the info in web
375
376 [[https:~~/~~/lorawan-packet-decoder-0ta6puiniaut.runkit.sh>>url:https://lorawan-packet-decoder-0ta6puiniaut.runkit.sh/]]
377
378 Need these three fields:
379
380 LoRa packet hex format: 40c1190126800100024926272bf18bbb6341584e27e23245 (from LG02)
381
382 AT+NWKSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 11 (End node Network Session Key)
383
384 AT+APPSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 11 (End Node App Session Key)
385
386 (((
387 [[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]]
388 )))
389
390 [[image:https://wiki.dragino.com/images/7/77/Decrypt_a_LoRaWAN_Packet4.png||alt="Decrypt a LoRaWAN Packet4.png" height="390" width="558"]]
391
392 The FRMPayload is the device payload.
393
394
395 = 8. Why i see uplink 0x00 periodcally on the LHT65 v1.8 firmware =
396
397 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.
398
399 = 9. Why do I see a "MIC Mismatch" error message from the server? =
400
401 (((
402 1)If the user receives a "MIC Mismatch" message after registering the node on the server.
403 )))
404
405 (((
406 It is likely that the user filled in the wrong APPKEY when registering the node. Many users fill in "APPSKEY".
407 )))
408
409 * (((
410 Please note the distinction between "APPKEY" and "APPSKEY".
411 )))
412
413 (((
414 2）If the node works on the server for a period of time, the device stops working and receives a "MIC Mismatch" message.
415 )))
416
417 (((
418 The user needs a USB-TTL adapter to connect the serial port to modify the node APPKEY.
419 )))
420
421 * (((
422 If a node is registered with multiple servers, it may also cause the "mic mismatch" error.
423 )))
424
425 = 10. Why i got the payload only with "0x00" or "AA~=~="? =
426
427 * (((
428 If you are using US915, AU915 and AS923 frequencies.This is normal phenomenon.
429 )))
430
431 (((
432 When using the frequency mentioned above, the server sometimes adjusts the rate of the node, because the node defaults to the adaptive rate.
433 )))
434
435 (((
436 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,
437 )))
438
439 (((
440 and the node will reply to the server after receiving the ADR packet, but the number of payload bytes exceeds the limit,
441 )))
442
443 (((
444 so it will send a normal uplink packet, and an additional 00 data packet.
445 )))
446
447 * (((
448 Solution: Use the decoder to filter out this 00 packet.
449 )))
450 * (((
451 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
452 )))
453
454 (% class="wikigeneratedid" id="H" %)
455