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Wiki source code of LoRaWAN Communication Debug

Version 3.1 by Xiaoling on 2022/05/11 14:23
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1
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 If user has problem to work with lorawan server in band US915/AU915/CN470, he can check:
64
65 * What **sub-band** the server support ?
66 * What is the **sub-band** the gateway support ?
67 * What is the **sub-band** the end node is using ?
68
69 All of above should match so End Node can properly Join the server and don't have packet lost.
70
71 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.
72
73 Here are the freuqency tables for these bands as reference:
74
75 [[image:https://wiki.dragino.com/images/thumb/3/3f/US915_FRE_BAND-1.png/600px-US915_FRE_BAND-1.png||height="170" width="600"]]
76
77 US915 Channels
78
79 [[image:https://wiki.dragino.com/images/thumb/8/8a/AU915_FRE_BAND-1.png/600px-AU915_FRE_BAND-1.png||height="167" width="600"]]
80
81 AU915 Channels
82
83 [[image:https://wiki.dragino.com/images/thumb/3/3a/CN470_FRE_BAND-1.png/600px-CN470_FRE_BAND-1.png||height="205" width="600"]]
84
85 CN470 Channels
86
87 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.
88
89 [[image:https://wiki.dragino.com/images/thumb/9/9a/US915_FRE_BAND-2.png/600px-US915_FRE_BAND-2.png||height="288" width="600"]]
90
91 TTN FREQUENCY PLAN
92
93 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. )
94
95
96 = 3. Why i see data lost/unperiocially uplink data? Even the signal strength is good =
97
98 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:
99
100 * **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.
101 * **Gateway** ~-~-> Use Sub-band2 (Channel 8,9,10,11,12,13,14,15) for Dragino Gateway. this is the default settings for dragino sensors.
102 * **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.
103
104 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.
105
106 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.
107
108
109 = 4. Transmision on ABP Mode =
110
111 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.
112
113 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.
114
115 To solve this, disable the Frame Counter Check will solve this issue , or reset the frame counter in the device page.
116
117 [[~[~[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]]
118
119 Disable Frame Counter Check in ABP Mode
120
121
122 = 5. Downstream Debug =
123
124 == 5.1 How it work ==
125
126 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.
127
128 Depends on Class A or Class C, the receive windows will be a little difference,
129
130 [[image:https://wiki.dragino.com/images/thumb/1/1a/Downstream_LoRaWAN-1.png/600px-Downstream_LoRaWAN-1.png||height="590" width="600"]]
131
132 receive windows for Class A and Class C
133
134 Below are the requirement for the End Device to receive the packets.
135
136 * The End Device must open the receive windows: RX1 or RX2
137 * The LoRaWAN server must send a downstream packet, and the gateway forward this downstream packet for this end node.
138 * This downstream packet must arrive to the end node while RX1 or RX2 is open.
139 * This packet must match the frequency of the RX1 or RX2 window.
140 * 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.**
141
142 == 5.2 See Debug Info ==
143
144 **For LoRaWAN Server**
145
146 We can check if there is downlink message for this end node, use TTN for example:
147
148 Configure a downstream to the end device
149
150 [[image:https://wiki.dragino.com/images/thumb/8/82/Downstream_debug_1.png/600px-Downstream_debug_1.png||height="217" width="600"]]
151
152 Set a downstream in TTN and see it is sent
153
154
155 This downstream info will then pass to the gateway downstream list. and include the DR which is used (SF9BW125) in EU868 is DR3
156
157 [[image:https://wiki.dragino.com/images/thumb/d/dc/Downstream_debug_2.png/600px-Downstream_debug_2.png||height="245" width="600"]]
158
159 Gateway Traffic can see this downstream info
160
161
162 **For LoRaWAN Gateway**
163
164 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:
165
166 [[image:https://wiki.dragino.com/images/thumb/2/21/Downstream_debug_3.png/600px-Downstream_debug_3.png||height="195" width="600"]]
167
168 Gateway Sent out this packet
169
170
171 **For End Node**
172
173 we can use AT Command (AT+CFG) to check the RX1 configure and RX2 configure. as below:
174
175 (% class="box infomessage" %)
176 (((
177 AT+RX2FQ=869525000 ~-~--> The RX2 Window frequency
178 )))
179
180 (% class="box infomessage" %)
181 (((
182 AT+RX2DR=3 ~-~--> The RX2 DataRate
183 )))
184
185 (% class="box infomessage" %)
186 (((
187 AT+RX1DL=1000 ~-~--> Receive Delay 1
188 )))
189
190 (% class="box infomessage" %)
191 (((
192 AT+RX2DL=2000 ~-~--> Receive Delay 2
193 )))
194
195 (((
196 {{info}}
197 (% class="box infomessage" %)
198 (((
199 AT+RX2FQ=869525000     ~-~--> The RX2 Window frequency
200 AT+RX2DR=3  ~-~--> The RX2 DataRate
201 AT+RX1DL=1000  ~-~--> Receive Delay 1
202 AT+RX2DL=2000  ~-~--> Receive Delay 2
203 )))
204 {{/info}}
205
206
207 )))
208
209 when the device running, we can see below info:
210
211 {{{[12502]***** UpLinkCounter= 0 *****
212 [12503]TX on freq 868500000 Hz at DR 0
213 [13992]txDone
214 [15022]RX on freq 868500000 Hz at DR 0 --> RX1 window open at frequency: 868500000, DR0, after 15022-13992= 1030ms of txdone
215 [15222]rxTimeOut --> no packet arrive in RX1 window. (duration: 200ms)
216 [15987]RX on freq 869525000 Hz at DR 3 --> RX2 window open at frequency: 869525000, DR3, after 15987-13992= 1995ms of txdone
217 [16027]rxTimeOut --> no packet arrive in RX2 window. (duration: 40 ms)
218 }}}
219
220 {{{Another message:
221 [12502]***** UpLinkCounter= 0 *****
222 [12503]TX on freq 868100000 Hz at DR 0
223 [13992]txDone
224 [15022]RX on freq 868100000 Hz at DR 0
225 [15222]rxTimeOut
226 [15987]RX on freq 869525000 Hz at DR 3
227 [16185]rxDone --> We have got the downstream packet.
228 Rssi= -64
229 Receive data
230 1:0012345678
231 }}}
232
233 == 5.3 If problem doesn’t solve ==
234
235 **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:**
236
237 * End node console to show the transmit freuqency and DR.
238 * Gateway (from gateway UI) traffic to show the packet got from end node and receive from Server.
239 * Gateway traffic (from server UI) to shows the data exchange between gateway and server.
240 * End Node traffic (from server UI) to shows end node activity in server.
241
242 = 6. Downlink Issue ~-~- Packet REJECTED, unsupported frequency =
243
244 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.
245
246 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:
247
248 {{{Sat Nov 21 08:04:17 2020 daemon.info lora_pkt_fwd[1680]: ERROR~ Packet REJECTED, unsupported frequency - 923200000 (min:865000000,max:867000000)
249 }}}
250
251 In this case, please double check the gateway frequency and the server frequency band.
252
253
254 = 7. Decrypt a LoRaWAN Packet =
255
256 ~1. LHT65 End device configure:
257
258 (% class="box infomessage" %)
259 (((
260 Change to ABP Mode: AT+NJM=0
261 )))
262
263 (% class="box infomessage" %)
264 (((
265 Change to fix frequency: AT+CHS=904900000
266 )))
267
268 (% class="box infomessage" %)
269 (((
270 Change to fix DR: AT+DR=0
271 )))
272
273 [[image:https://wiki.dragino.com/images/e/e6/Decrypt_a_LoRaWAN_Packet1.jpg||alt="Decrypt a LoRaWAN Packet1.jpg" height="607" width="558"]]
274
275 2. In LG02 , configure to receive above message
276
277 [[image:https://wiki.dragino.com/images/c/c3/Decrypt_a_LoRaWAN_Packet2.jpg||alt="Decrypt a LoRaWAN Packet2.jpg" height="337" width="558"]]
278
279 In LG02 console, we can see the hex receive are:
280
281 [[image:https://wiki.dragino.com/images/f/f1/Decrypt_a_LoRaWAN_Packet3.jpg||alt="Decrypt a LoRaWAN Packet3.jpg" height="179" width="558"]]
282
283 3. Decode the info in web
284
285 [[https:~~/~~/lorawan-packet-decoder-0ta6puiniaut.runkit.sh>>url:https://lorawan-packet-decoder-0ta6puiniaut.runkit.sh/]]
286
287 Need these three fields:
288
289 LoRa packet hex format: 40c1190126800100024926272bf18bbb6341584e27e23245 (from LG02)
290
291 AT+NWKSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 11 (End node Network Session Key)
292
293 AT+APPSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 11 (End Node App Session Key)
294
295 [[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]]
296
297 [[image:https://wiki.dragino.com/images/7/77/Decrypt_a_LoRaWAN_Packet4.png||alt="Decrypt a LoRaWAN Packet4.png" height="390" width="558"]]
298
299 The FRMPayload is the device payload.
300
301
302 = 8. Why i see uplink 0x00 periodcally on the LHT65 v1.8 firmware =
303
304 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.
305
306 = 9. Why do I see a "MIC Mismatch" error message from the server? =
307
308 1)If the user receives a "MIC Mismatch" message after registering the node on the server.
309
310 It is likely that the user filled in the wrong APPKEY when registering the node. Many users fill in "APPSKEY".
311
312 * Please note the distinction between "APPKEY" and "APPSKEY".
313
314 2）If the node works on the server for a period of time, the device stops working and receives a "MIC Mismatch" message.
315
316 The user needs a USB-TTL adapter to connect the serial port to modify the node APPKEY.
317
318 * If a node is registered with multiple servers, it may also cause the "mic mismatch" error.
319
320 = 10. Why i got the payload only with "0x00" or "AA~=~="? =
321
322 * If you are using US915, AU915 and AS923 frequencies.This is normal phenomenon.
323
324 When using the frequency mentioned above, the server sometimes adjusts the rate of the node, because the node defaults to the adaptive rate.
325
326 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,
327
328 and the node will reply to the server after receiving the ADR packet, but the number of payload bytes exceeds the limit,
329
330 so it will send a normal uplink packet, and an additional 00 data packet.
331
332 * Solution: Use the decoder to filter out this 00 packet.
333 * 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
334
335 (% class="wikigeneratedid" id="H" %)
336