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Wiki source code of LoRaWAN Communication Debug

Version 1.1 by Xiaoling on 2022/05/11 13:43
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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
18 **~1. End Device Join Screen shot, we can check:**
19
20 * If the device is sending join request to server?
21 * What frequency the device is sending?
22
23 [[~[~[image:https://wiki.dragino.com/images/thumb/0/0f/OTAA_Join-1.jpg/600px-OTAA_Join-1.jpg~|~|height="316" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:OTAA_Join-1.jpg]]
24
25 Console Output from End device to see the transmit frequency
26
27
28 **2. Gateway packet traffic in gateway web or ssh. we can check:**
29
30 * If the gateway receive the Join request packet from sensor? (If this fail, check if the gateway and sensor works on the match frequency)
31 * If the gateway gets the Join Accept message from server and transmit it via LoRa?
32
33 [[~[~[image:https://wiki.dragino.com/images/thumb/1/1c/OTAA_Join-2.png/600px-OTAA_Join-2.png~|~|height="325" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:OTAA_Join-2.png]]
34
35 Console Output from Gateway to see packets between end node and server.
36
37
38 **3. Gateway Traffic Page in LoRaWAN Server**
39
40 * If the Join Request packet arrive the gateway traffic in server? If not, check the internet connection and gateway LoRaWAN server settings.
41 * 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.
42 * 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.
43
44 [[~[~[image:https://wiki.dragino.com/images/thumb/5/5c/OTAA_Join-3.png/600px-OTAA_Join-3.png~|~|height="301" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:OTAA_Join-3.png]]
45
46 The Traffic for the End node in the server, use TTN as example
47
48
49 **4. Data Page in LoRaWAN server**
50
51 * 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.
52
53 [[~[~[image:https://wiki.dragino.com/images/thumb/e/ec/OTAA_Join-4.png/600px-OTAA_Join-4.png~|~|height="181" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:OTAA_Join-4.png]]
54
55 The data for the end device set in server
56
57 [[~[~[image:https://wiki.dragino.com/images/thumb/b/b1/OTAA_Join-5.png/600px-OTAA_Join-5.png~|~|height="166" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:OTAA_Join-5.png]]
58
59 Check if OTAA Keys match the keys in device
60
61
62 = Notice of US915/CN470/AU915 Frequency band =
63
64 If user has problem to work with lorawan server in band US915/AU915/CN470, he can check:
65
66 * What sub-band the server support ?
67 * What is the sub-band the gateway support ?
68 * What is the sub-band the end node is using ?
69
70 All of above should match so End Node can properly Join the server and don't have packet lost.
71
72 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.
73
74 Here are the freuqency tables for these bands as reference:
75
76 [[~[~[image:https://wiki.dragino.com/images/thumb/3/3f/US915_FRE_BAND-1.png/600px-US915_FRE_BAND-1.png~|~|height="170" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:US915_FRE_BAND-1.png]]
77
78 US915 Channels
79
80 [[~[~[image:https://wiki.dragino.com/images/thumb/8/8a/AU915_FRE_BAND-1.png/600px-AU915_FRE_BAND-1.png~|~|height="167" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:AU915_FRE_BAND-1.png]]
81
82 AU915 Channels
83
84 [[~[~[image:https://wiki.dragino.com/images/thumb/3/3a/CN470_FRE_BAND-1.png/600px-CN470_FRE_BAND-1.png~|~|height="205" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:CN470_FRE_BAND-1.png]]
85
86 CN470 Channels
87
88 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.
89
90 [[~[~[image:https://wiki.dragino.com/images/thumb/9/9a/US915_FRE_BAND-2.png/600px-US915_FRE_BAND-2.png~|~|height="288" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:US915_FRE_BAND-2.png]]
91
92 TTN FREQUENCY PLAN
93
94 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. )
95
96
97 = Why i see data lost/unperiocially uplink data? Even the signal strength is good =
98
99 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:
100
101 * 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.
102 * Gateway ~-~-> Use Sub-band2 (Channel 8,9,10,11,12,13,14,15) for Dragino Gateway. this is the default settings for dragino sensors.
103 * 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.
104
105 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.
106
107 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.
108
109
110 = Transmision on ABP Mode =
111
112 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.
113
114 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.
115
116 To solve this, disable the Frame Counter Check will solve this issue , or reset the frame counter in the device page.
117
118 [[~[~[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]]
119
120 Disable Frame Counter Check in ABP Mode
121
122
123 = Downstream Debug =
124
125 == How it work ==
126
127 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.
128
129 Depends on Class A or Class C, the receive windows will be a little difference,
130
131 [[~[~[image:https://wiki.dragino.com/images/thumb/1/1a/Downstream_LoRaWAN-1.png/600px-Downstream_LoRaWAN-1.png~|~|height="590" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:Downstream_LoRaWAN-1.png]]
132
133 receive windows for Class A and Class C
134
135 Below are the requirement for the End Device to receive the packets.
136
137 * The End Device must open the receive windows: RX1 or RX2
138 * The LoRaWAN server must send a downstream packet, and the gateway forward this downstream packet for this end node.
139 * This downstream packet must arrive to the end node while RX1 or RX2 is open.
140 * This packet must match the frequency of the RX1 or RX2 window.
141 * 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.
142
143
144 == See Debug Info ==
145
146 For LoRaWAN Server
147
148 We can check if there is downlink message for this end node, use TTN for example:
149
150 Configure a downstream to the end device
151
152 [[~[~[image:https://wiki.dragino.com/images/thumb/8/82/Downstream_debug_1.png/600px-Downstream_debug_1.png~|~|height="217" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:Downstream_debug_1.png]]
153
154 Set a downstream in TTN and see it is sent
155
156
157 This downstream info will then pass to the gateway downstream list. and include the DR which is used (SF9BW125) in EU868 is DR3
158
159 [[~[~[image:https://wiki.dragino.com/images/thumb/d/dc/Downstream_debug_2.png/600px-Downstream_debug_2.png~|~|height="245" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:Downstream_debug_2.png]]
160
161 Gateway Traffic can see this downstream info
162
163
164 For LoRaWAN Gateway
165
166 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:
167
168 [[~[~[image:https://wiki.dragino.com/images/thumb/2/21/Downstream_debug_3.png/600px-Downstream_debug_3.png~|~|height="195" width="600"~]~]>>url:https://wiki.dragino.com/index.php/File:Downstream_debug_3.png]]
169
170 Gateway Sent out this packet
171
172
173 For End Node
174
175 we can use AT Command (AT+CFG) to check the RX1 configure and RX2 configure. as below:
176
177 {{{AT+RX2FQ=869525000 ---> The RX2 Window frequency
178 AT+RX2DR=3 ---> The RX2 DataRate
179 AT+RX1DL=1000 ---> Receive Delay 1
180 AT+RX2DL=2000 ---> Receive Delay 2
181 }}}
182
183 when the device running, we can see below info:
184
185 {{{[12502]***** UpLinkCounter= 0 *****
186 [12503]TX on freq 868500000 Hz at DR 0
187 [13992]txDone
188 [15022]RX on freq 868500000 Hz at DR 0 --> RX1 window open at frequency: 868500000, DR0, after 15022-13992= 1030ms of txdone
189 [15222]rxTimeOut --> no packet arrive in RX1 window. (duration: 200ms)
190 [15987]RX on freq 869525000 Hz at DR 3 --> RX2 window open at frequency: 869525000, DR3, after 15987-13992= 1995ms of txdone
191 [16027]rxTimeOut --> no packet arrive in RX2 window. (duration: 40 ms)
192 }}}
193
194 {{{Another message:
195 [12502]***** UpLinkCounter= 0 *****
196 [12503]TX on freq 868100000 Hz at DR 0
197 [13992]txDone
198 [15022]RX on freq 868100000 Hz at DR 0
199 [15222]rxTimeOut
200 [15987]RX on freq 869525000 Hz at DR 3
201 [16185]rxDone --> We have got the downstream packet.
202 Rssi= -64
203 Receive data
204 1:0012345678
205 }}}
206
207 == If problem doesn’t solve ==
208
209 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:
210
211 * End node console to show the transmit freuqency and DR.
212 * Gateway (from gateway UI) traffic to show the packet got from end node and receive from Server.
213 * Gateway traffic (from server UI) to shows the data exchange between gateway and server.
214 * End Node traffic (from server UI) to shows end node activity in server.
215
216
217
218 = Downlink Issue ~-~- Packet REJECTED, unsupported frequency =
219
220 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.
221
222 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:
223
224 {{{Sat Nov 21 08:04:17 2020 daemon.info lora_pkt_fwd[1680]: ERROR~ Packet REJECTED, unsupported frequency - 923200000 (min:865000000,max:867000000)
225 }}}
226
227 In this case, please double check the gateway frequency and the server frequency band.
228
229
230
231 = Decrypt a LoRaWAN Packet =
232
233 ~1. LHT65 End device configure:
234
235 Change to ABP Mode: AT+NJM=0
236
237 Change to fix frequency: AT+CHS=904900000
238
239 Change to fix DR: AT+DR=0
240
241 [[~[~[image:https://wiki.dragino.com/images/e/e6/Decrypt_a_LoRaWAN_Packet1.jpg~|~|alt="Decrypt a LoRaWAN Packet1.jpg" height="607" width="558"~]~]>>url:https://wiki.dragino.com/index.php/File:Decrypt_a_LoRaWAN_Packet1.jpg]]
242
243 2. In LG02 , configure to receive above message
244
245 [[~[~[image:https://wiki.dragino.com/images/c/c3/Decrypt_a_LoRaWAN_Packet2.jpg~|~|alt="Decrypt a LoRaWAN Packet2.jpg" height="337" width="558"~]~]>>url:https://wiki.dragino.com/index.php/File:Decrypt_a_LoRaWAN_Packet2.jpg]]
246
247 In LG02 console, we can see the hex receive are:
248
249 [[~[~[image:https://wiki.dragino.com/images/f/f1/Decrypt_a_LoRaWAN_Packet3.jpg~|~|alt="Decrypt a LoRaWAN Packet3.jpg" height="179" width="558"~]~]>>url:https://wiki.dragino.com/index.php/File:Decrypt_a_LoRaWAN_Packet3.jpg]]
250
251 3. Decode the info in web
252
253 [[https:~~/~~/lorawan-packet-decoder-0ta6puiniaut.runkit.sh>>url:https://lorawan-packet-decoder-0ta6puiniaut.runkit.sh/]]
254
255 Need these three fields:
256
257 LoRa packet hex format: 40c1190126800100024926272bf18bbb6341584e27e23245 (from LG02)
258
259 AT+NWKSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 11 (End node Network Session Key)
260
261 AT+APPSKEY=00 00 00 00 00 00 00 00 00 00 00 00 00 00 01 11 (End Node App Session Key)
262
263 [[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]]
264
265 [[~[~[image:https://wiki.dragino.com/images/7/77/Decrypt_a_LoRaWAN_Packet4.png~|~|alt="Decrypt a LoRaWAN Packet4.png" height="390" width="558"~]~]>>url:https://wiki.dragino.com/index.php/File:Decrypt_a_LoRaWAN_Packet4.png]]
266
267 The FRMPayload is the device payload.
268
269
270 = Why i see uplink 0x00 periodcally on the LHT65 v1.8 firmware =
271
272 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.
273
274 = Why do I see a "MIC Mismatch" error message from the server? =
275
276 1)If the user receives a "MIC Mismatch" message after registering the node on the server.
277
278 It is likely that the user filled in the wrong APPKEY when registering the node. Many users fill in "APPSKEY".
279
280 * Please note the distinction between "APPKEY" and "APPSKEY".
281
282 2）If the node works on the server for a period of time, the device stops working and receives a "MIC Mismatch" message.
283
284 The user needs a USB-TTL adapter to connect the serial port to modify the node APPKEY.
285
286 * If a node is registered with multiple servers, it may also cause the "mic mismatch" error.
287
288 = Why i got the payload only with "0x00" or "AA~=~="? =
289
290 * If you are using US915, AU915 and AS923 frequencies.This is normal phenomenon.
291
292 When using the frequency mentioned above, the server sometimes adjusts the rate of the node, because the node defaults to the adaptive rate.
293
294 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,
295
296 and the node will reply to the server after receiving the ADR packet, but the number of payload bytes exceeds the limit,
297
298 so it will send a normal uplink packet, and an additional 00 data packet.
299
300 * Solution: Use the decoder to filter out this 00 packet.
301 * 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
302
303 == ==