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Version 175.20 by Xiaoling on 2022/06/15 11:08
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1 (% style="text-align:center" %)
2 [[image:1655254599445-662.png]]
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5
6
7 **Table of Contents:**
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15
16 = 1.  Introduction =
17
18 == 1.1 ​ What is LoRaWAN Ultrasonic liquid level Sensor ==
19
20 (((
21
22
23 (((
24 (((
25 (((
26 The Dragino LDDS20 is a (% style="color:#4472c4" %)**LoRaWAN Ultrasonic liquid level sensor**(%%) for Internet of Things solution. It uses (% style="color:#4472c4" %)**none-contact method **(%%)to measure the height of liquid in a container without opening the container, and send the value via LoRaWAN network to IoT Server
27 )))
28
29 (((
30
31 )))
32
33 (((
34 The LDDS20 sensor is installed directly below the container to detect the height of the liquid level. User doesn’t need to open a hole on the container to be tested. The (% style="color:#4472c4" %)**none-contact measurement makes the measurement safety, easier and possible for some strict situation**. 
35 )))
36
37 (((
38
39 )))
40
41 (((
42 LDDS20 uses ultrasonic sensing technology for distance measurement. LDDS20 is of high accuracy to measure various liquid such as: (% style="color:#4472c4" %)**toxic substances**(%%), (% style="color:#4472c4" %)**strong acids**(%%), (% style="color:#4472c4" %)**strong alkalis**(%%) and (% style="color:#4472c4" %)**various pure liquids**(%%) in high-temperature and high-pressure airtight containers.
43 )))
44
45 (((
46
47 )))
48
49 (((
50 The LoRa wireless technology used in LDDS20 allows device to send data and reach extremely long ranges at low data-rates. It provides ultra-long range spread spectrum communication and high interference immunity whilst minimizing current consumption.
51 )))
52
53 (((
54
55 )))
56
57 (((
58 LDDS20 is powered by (% style="color:#4472c4" %)**8500mA Li-SOCI2 battery**(%%); It is designed for long term use up to 10 years*.
59 )))
60
61 (((
62
63 )))
64
65 (((
66 Each LDDS20 pre-loads with a set of unique keys for LoRaWAN registrations, register these keys to local LoRaWAN server and it will auto connect if there is network coverage, after power on.
67 )))
68
69 (((
70
71 )))
72 )))
73
74 (((
75 (((
76 (% style="color:#4472c4" %) * (%%)Actually lifetime depends on network coverage and uplink interval and other factors.
77 )))
78 )))
79 )))
80 )))
81
82
83 [[image:1655255122126-327.png]]
84
85
86
87 == ​1.2  Features ==
88
89 * LoRaWAN 1.0.3 Class A
90 * Ultra low power consumption
91 * Liquid Level Measurement by Ultrasonic technology
92 * Measure through container, No need to contact Liquid.
93 * Valid level range 20mm - 2000mm
94 * Accuracy: ±(5mm+S*0.5%) (S: Measure Value)
95 * Cable Length : 25cm
96 * Bands: CN470/EU433/KR920/US915/EU868/AS923/AU915/IN865
97 * AT Commands to change parameters
98 * Uplink on periodically
99 * Downlink to change configure
100 * IP66 Waterproof Enclosure
101 * 8500mAh Battery for long term use
102
103
104
105
106 == 1.3  Suitable Container & Liquid ==
107
108 * Solid Wall container such as: steel, iron, glass, ceramics, non-foaming plastics etc.
109 * Container shape is regular, and surface is smooth.
110 * Container Thickness:
111 ** Pure metal material.  2~~8mm, best is 3~~5mm
112 ** Pure non metal material: <10 mm
113 * Pure liquid without irregular deposition.
114
115
116
117
118 == 1.4  Mechanical ==
119
120 [[image:image-20220615090910-1.png]]
121
122
123 [[image:image-20220615090910-2.png]]
124
125
126
127 == 1.5  Install LDDS20 ==
128
129
130 (% style="color:blue" %)**Step 1**(%%):  Choose the installation point.
131
132 LDDS20 (% style="color:red" %)**MUST**(%%) be installed on the container bottom middle position.
133
134 [[image:image-20220615091045-3.png]]
135
136
137
138 (% style="color:blue" %)**Step 2**(%%):  Polish the installation point.
139
140 For Metal Surface with paint, it is important to polish the surface, first use crude sand paper to polish the paint level , then use exquisite sand paper to polish the metal level to make it shine & smooth.
141
142 [[image:image-20220615092010-11.png]]
143
144
145 No polish needed if the container is shine metal surface without paint or non-metal container.
146
147 [[image:image-20220615092044-12.png]]
148
149
150
151 (% style="color:blue" %)**Step3:   **(%%)Test the installation point.
152
153 Power on LDDS75, check if the blue LED is on, If the blue LED is on, means the sensor works. Then put ultrasonic coupling paste on the sensor and put it tightly on the installation point.
154
155
156 It is necessary to put the coupling paste between the sensor and the container, otherwise LDDS20 won’t detect the liquid level.
157
158 [[image:1655256160324-178.png]][[image:image-20220615092327-13.png]]
159
160
161 After paste the LDDS20 well, power on LDDS20. In the first 30 seconds of booting, device will check the sensors status and BLUE LED will show the status as below. After 30 seconds, BLUE LED will be off to save battery life.
162
163
164 (% style="color:red" %)**LED Status:**
165
166 * Onboard LED: When power on device, the onboard LED will fast blink 4 times which means detect the sensor well.
167
168 * (% style="color:blue" %)BLUE LED(% style="color:red" %) always ON(%%): Sensor is power on but doesn’t detect liquid. There is problem in installation point.
169 * (% style="color:blue" %)BLUE LED(% style="color:red" %) slowly blinking(%%): Sensor detects Liquid Level, The installation point is good.
170
171 LDDS20 will enter into low power mode at 30 seconds after system reset or power on, Blue LED will be off after that.
172
173
174 (% style="color:red" %)**Note 2:**
175
176 (% style="color:red" %)Ultrasonic coupling paste (%%) is subjected in most shipping way. So the default package doesn’t include it and user needs to purchase locally.
177
178
179
180 (% style="color:blue" %)**Step4:   **(%%)Install use Epoxy ab glue.
181
182 Prepare Eproxy AB glue.
183
184 Put Eproxy AB glue in the sensor and press it hard on the container installation point.
185
186 Reset LDDS20 and see if the BLUE LED is slowly blinking.
187
188 [[image:image-20220615091045-8.png||height="226" width="380"]] [[image:image-20220615091045-9.png||height="239" width="339"]]
189
190
191 (% style="color:red" %)**Note 1:**
192
193 Eproxy AB glue needs 3~~ 5 minutes to stable attached. we can use other glue material to keep it in the position.
194
195
196 (% style="color:red" %)**Note 2:**
197
198 (% style="color:red" %)Eproxy AB glue(%%) is subjected in most shipping way. So the default package doesn’t include it and user needs to purchase locally.
199
200
201
202 == 1.6 ​ Applications ==
203
204 * Smart liquid control solution.
205 * Smart liquefied gas solution.
206
207
208
209
210 == 1.7  Precautions ==
211
212 * At room temperature, containers of different materials, such as steel, glass, iron, ceramics, non-foamed plastics and other dense materials, have different detection blind areas and detection limit heights.
213 * For containers of the same material at room temperature, the detection blind zone and detection limit height are also different for the thickness of the container.
214 * When the detected liquid level exceeds the effective detection value of the sensor, and the liquid level of the liquid to be measured shakes or tilts, the detected liquid height is unstable.
215
216 == 1.8  Pin mapping and power on ==
217
218
219 [[image:1655257026882-201.png]]
220
221
222
223 = 2.  Configure LDDS20 to connect to LoRaWAN network =
224
225
226 == 2.1  How it works ==
227
228 (((
229 The LDDS20 is configured as LoRaWAN OTAA Class A mode by default. It has OTAA keys to join LoRaWAN network. To connect a LoRaWAN network, you need to input the OTAA keys in the LoRaWAN IoT server and power on the LDDS20. If there is coverage of the LoRaWAN network, it will automatically join the network via OTAA and start to send the sensor value.
230 )))
231
232 (((
233 In case you can't set the OTAA keys in the LoRaWAN OTAA server, and you have to use the keys from the server, you can [[use AT Commands >>||anchor="H3.A0UsingtheATCommands"]]to set the keys in the LDDS20.
234 )))
235
236
237
238 == 2.2  ​Quick guide to connect to LoRaWAN server (OTAA) ==
239
240 (((
241 Following is an example for how to join the [[TTN v3 LoRaWAN Network>>url:https://console.cloud.thethings.network/]]. Below is the network structure; we use the [[LG308>>url:http://www.dragino.com/products/lora/item/140-lg308.html]] as a LoRaWAN gateway in this example.
242 )))
243
244 (((
245 [[image:1655257698953-697.png]]
246 )))
247
248 (((
249 The LG308 is already set to connected to [[TTN network >>url:https://console.cloud.thethings.network/]], so what we need to now is configure the TTN server.
250 )))
251
252 (((
253
254
255 (% style="color:blue" %)**Step 1**(%%): Create a device in TTN with the OTAA keys from LDDS20.
256 )))
257
258 (((
259 Each LDDS20 is shipped with a sticker with the default device keys, user can find this sticker in the box. it looks like below.
260 )))
261
262 [[image:image-20220607170145-1.jpeg]]
263
264
265 (((
266 For OTAA registration, we need to set **APP EUI/ APP KEY/ DEV EUI**. Some server might no need to set APP EUI.
267 )))
268
269 (((
270 Enter these keys in the LoRaWAN Server portal. Below is TTN V3 screen shot:
271 )))
272
273 (((
274
275
276 **Add APP EUI in the application**
277 )))
278
279 [[image:image-20220610161353-4.png]]
280
281 [[image:image-20220610161353-5.png]]
282
283 [[image:image-20220610161353-6.png]]
284
285
286 [[image:image-20220610161353-7.png]]
287
288
289
290 You can also choose to create the device manually.
291
292 [[image:image-20220610161538-8.png]]
293
294
295
296 **Add APP KEY and DEV EUI**
297
298 [[image:image-20220610161538-9.png]]
299
300
301
302 (% style="color:blue" %)**Step 2**(%%):  Power on LDDS20
303
304
305 Put a Jumper on JP2 to power on the device. ( The Switch must be in FLASH position).
306
307 [[image:image-20220615095102-14.png]]
308
309
310
311 (((
312 (% style="color:blue" %)**Step 3**(%%)**:**  The LDDS20 will auto join to the TTN network. After join success, it will start to upload messages to TTN and you can see the messages in the panel.
313 )))
314
315 [[image:1654849068701-275.png]]
316
317
318
319 == 2.3  ​Uplink Payload ==
320
321 (((
322 (((
323 LDDS20 will uplink payload via LoRaWAN with below payload format: 
324
325 Uplink payload includes in total 8 bytes.
326 Payload for firmware version v1.1.4. . Before v1.1.3, there is only 5 bytes: BAT and Distance(Please check manual v1.2.0 if you have 5 bytes payload).
327 )))
328 )))
329
330 (((
331
332 )))
333
334 (% border="1" cellspacing="10" style="background-color:#ffffcc; width:510px" %)
335 |=(% style="width: 62.5px;" %)(((
336 **Size (bytes)**
337 )))|=(% style="width: 62.5px;" %)**2**|=**2**|=1|=2|=**1**
338 |(% style="width:62.5px" %)**Value**|(% style="width:62.5px" %)[[BAT>>||anchor="H2.3.1A0BatteryInfo"]]|(((
339 [[Distance>>||anchor="H2.3.2A0Distance"]]
340
341 (unit: mm)
342 )))|[[Digital Interrupt (Optional)>>||anchor="H2.3.3A0InterruptPin"]]|(((
343 [[Temperature (Optional )>>||anchor="H2.3.4A0DS18B20Temperaturesensor"]]
344 )))|[[Sensor Flag>>||anchor="H2.3.5A0SensorFlag"]]
345
346 [[image:1654850511545-399.png]]
347
348
349
350 === 2.3.1  Battery Info ===
351
352
353 Check the battery voltage for LDDS20.
354
355 Ex1: 0x0B45 = 2885mV
356
357 Ex2: 0x0B49 = 2889mV
358
359
360
361 === 2.3.2  Distance ===
362
363 (((
364 Get the distance. Flat object range 20mm - 2000mm.
365 )))
366
367 (((
368 For example, if the data you get from the register is __0x06 0x05__, the distance between the sensor and the measured object is(% style="color:#4472c4" %)** 0605(H) = 1541 (D) = 1541 mm.**
369 )))
370
371 * If the sensor value is 0x0000, it means system doesn't detect ultrasonic sensor.
372 * If the sensor value lower than 0x0014 (20mm), the sensor value will be invalid.
373
374 === 2.3.3  Interrupt Pin ===
375
376 This data field shows if this packet is generated by interrupt or not. [[Click here>>||anchor="H3.2A0SetInterruptMode"]] for the hardware and software set up.
377
378 **Example:**
379
380 0x00: Normal uplink packet.
381
382 0x01: Interrupt Uplink Packet.
383
384
385
386 === 2.3.4  DS18B20 Temperature sensor ===
387
388 This is optional, user can connect external DS18B20 sensor to the +3.3v, 1-wire and GND pin . and this field will report temperature.
389
390 **Example**:
391
392 If payload is: 0105H:  (0105 & FC00 == 0), temp = 0105H /10 = 26.1 degree
393
394 If payload is: FF3FH :  (FF3F & FC00 == 1) , temp = (FF3FH - 65536)/10 = -19.3 degrees.
395
396 (% style="color:red" %)Note: DS18B20 feature is supported in the hardware version > v1.3 which made since early of 2021.
397
398
399
400 === 2.3.5  Sensor Flag ===
401
402 (((
403 0x01: Detect Ultrasonic Sensor
404 )))
405
406 (((
407 0x00: No Ultrasonic Sensor
408 )))
409
410
411
412 === 2.3.6  Decode payload in The Things Network ===
413
414 While using TTN network, you can add the payload format to decode the payload.
415
416
417 [[image:1655261164557-670.png]]
418
419 The payload decoder function for TTN V3 is here:
420
421 (((
422 LDDS20 TTN V3 Payload Decoder: [[http:~~/~~/www.dragino.com/downloads/index.php?dir=LoRa_End_Node/LDDS20/Payload_Decoder/>>url:http://www.dragino.com/downloads/index.php?dir=LoRa_End_Node/LSE01/Payload_Decoder/]]
423 )))
424
425
426
427 == 2.4  Downlink Payload ==
428
429 By default, LDDS20 prints the downlink payload to console port.
430
431 [[image:image-20220615100930-15.png]]
432
433
434 **Examples:**
435
436
437 * (% style="color:blue" %)**Set TDC**
438
439 If the payload=0100003C, it means set the END Node's TDC to 0x00003C=60(S), while type code is 01.
440
441 Payload:    01 00 00 1E    TDC=30S
442
443 Payload:    01 00 00 3C    TDC=60S
444
445
446 * (% style="color:blue" %)**Reset**
447
448 If payload = 0x04FF, it will reset the LDDS20
449
450
451 * (% style="color:blue" %)**CFM**
452
453 Downlink Payload: 05000001, Set AT+CFM=1 or 05000000 , set AT+CFM=0
454
455
456
457 == 2.5  ​Show Data in DataCake IoT Server ==
458
459 (((
460 [[DATACAKE>>url:https://datacake.co/]] provides a human friendly interface to show the sensor data, once we have data in TTN, we can use [[DATACAKE>>url:https://datacake.co/]] to connect to TTN and see the data in DATACAKE. Below are the steps:
461 )))
462
463 (((
464
465 )))
466
467 (((
468 (% style="color:blue" %)**Step 1**(%%)**: Be sure that your device is programmed and properly connected to the network at this time.**
469 )))
470
471 (((
472 (% style="color:blue" %)**Step 2**(%%)**: To configure the Application to forward data to DATACAKE you will need to add integration. To add the DATACAKE integration, perform the following steps:**
473 )))
474
475
476 [[image:1654592790040-760.png]]
477
478
479 [[image:1654592800389-571.png]]
480
481
482 (% style="color:blue" %)**Step 3**(%%)**: Create an account or log in Datacake.**
483
484 (% style="color:blue" %)**Step 4**(%%)**: Search the LDDS75 and add DevEUI.(% style="color:red" %)(Note: LDDS20 use same payload as LDDS75)(%%)**
485
486 [[image:1654851029373-510.png]]
487
488
489 After added, the sensor data arrive TTN V3, it will also arrive and show in Datacake.
490
491 [[image:image-20220610165129-11.png||height="595" width="1088"]]
492
493
494
495 == 2.6  LED Indicator ==
496
497 The LDDS20 has an internal LED which is to show the status of different state.
498
499
500 * Blink once when device power on.
501 * The device detects the sensor and flashes 5 times.
502 * Solid ON for 5 seconds once device successful Join the network.
503 * Blink once when device transmit a packet.
504
505 == 2.7  ​Firmware Change Log ==
506
507
508 (((
509 **Firmware download link:  **[[http:~~/~~/www.dragino.com/downloads/index.php?dir=LoRa_End_Node/LSE01/Firmware/>>url:http://www.dragino.com/downloads/index.php?dir=LoRa_End_Node/LSE01/Firmware/]]
510 )))
511
512 (((
513
514 )))
515
516 (((
517 **Firmware Upgrade Method:  [[Firmware Upgrade Instruction>>doc:Main.Firmware Upgrade Instruction for STM32 base products.WebHome]]**
518 )))
519
520
521
522 == 2.8  Battery Analysis ==
523
524
525
526
527 === 2.8.1  Battery Type ===
528
529 The LDDS20 battery is a combination of a 8500mAh Li/SOCI2 Battery and a Super Capacitor. The battery is non-rechargeable battery type with a low discharge rate (<2% per year). This type of battery is commonly used in IoT devices such as water meter.
530
531
532 The battery related documents as below:
533
534 * (((
535 [[Battery Dimension>>https://www.dragino.com/downloads/index.php?dir=datasheet/Battery/ER26500/]],
536 )))
537 * (((
538 [[Lithium-Thionyl Chloride Battery  datasheet>>https://www.dragino.com/downloads/index.php?dir=datasheet/Battery/ER26500/]],
539 )))
540 * (((
541 [[Lithium-ion Battery-Capacitor datasheet>>https://www.dragino.com/downloads/index.php?dir=datasheet/Battery/ER26500/]]
542 )))
543
544 [[image:image-20220615102527-16.png]]
545
546
547
548 == 2.8.2  Battery Note ==
549
550 The Li-SICO battery is designed for small current / long period application. It is not good to use a high current, short period transmit method. The recommended minimum period for use of this battery is 5 minutes. If you use a shorter period time to uplink data, then the battery life may be decreased.
551
552
553
554 === 2.8.3  Replace the battery ===
555
556 (((
557 You can change the battery in the LDDS75.The type of battery is not limited as long as the output is between 3v to 3.6v. On the main board, there is a diode (D1) between the battery and the main circuit. If you need to use a battery with less than 3.3v, please remove the D1 and shortcut the two pads of it so there won't be voltage drop between battery and main board.
558 )))
559
560 (((
561
562 )))
563
564 (((
565 The default battery pack of LDDS75 includes a ER18505 plus super capacitor. If user can't find this pack locally, they can find ER18505 or equivalence, which will also work in most case. The SPC can enlarge the battery life for high frequency use (update period below 5 minutes)
566 )))
567
568
569
570 == 2.8.4  Battery Life Analyze ==
571
572 Dragino battery powered products are all run in Low Power mode. User can check the guideline from this link to calculate the estimate battery life:
573
574 [[https:~~/~~/www.dragino.com/downloads/downloads/LoRa_End_Node/Battery_Analyze/DRAGINO_Battery_Life_Guide.pdf>>url:https://www.dragino.com/downloads/downloads/LoRa_End_Node/Battery_Analyze/DRAGINO_Battery_Life_Guide.pdf]]
575
576
577
578 = 3.  Using the AT Commands =
579
580 (((
581 (((
582
583 )))
584 )))
585
586 == 3.1  Access AT Commands ==
587
588 LDDS20 supports AT Command set in the stock firmware. You can use a USB to TTL adapter to connect to LDDS20 for using AT command, as below.
589
590
591 [[image:image-20220610172924-4.png||height="483" width="988"]]
592
593
594 Or if you have below board, use below connection:
595
596
597 [[image:image-20220610172924-5.png]]
598
599
600 (((
601 In the PC, you need to set the serial baud rate to (% style="color:green" %)**9600**(%%) to access the serial console for LDDS20. LDDS20 will output system info once power on as below:
602 )))
603
604
605 [[image:image-20220610172924-6.png||height="601" width="860"]]
606
607 Below are the available commands, a more detailed AT Command manual can be found at [[AT Command Manual>>https://www.dragino.com/downloads/index.php?dir=LoRa_End_Node/LSE01/]].
608
609
610 AT+<CMD>?  :  Help on <CMD>
611
612 AT+<CMD>  :  Run <CMD>
613
614 AT+<CMD>=<value>  :  Set the value
615
616 AT+<CMD>=?  :  Get the value
617
618
619 (% style="color:#037691" %)** General Commands :**     
620
621 AT  :  Attention       
622
623 AT?  :  Short Help     
624
625 ATZ :  MCU Reset    
626
627 AT+TDC :  Application Data Transmission Interval 
628
629
630 (% style="color:#037691" %)** Keys, IDs and EUIs management :**
631
632 AT+APPEUI  :  Application EUI      
633
634 AT+APPKEY  :  Application Key     
635
636 AT+APPSKEY  :  Application Session Key
637
638 AT+DADDR :  Device Address     
639
640 AT+DEUI :  Device EUI     
641
642 AT+NWKID  :  Network ID (You can enter this command change only after successful network connection) 
643
644 AT+NWKSKEY  : Network Session Key Joining and sending date on LoRa network  
645
646 AT+CFM :  Confirm Mode       
647
648 AT+CFS :  Confirm Status       
649
650 AT+JOIN  :  Join LoRa? Network       
651
652 AT+NJM  :  LoRa? Network Join Mode    
653
654 AT+NJS  :  LoRa? Network Join Status    
655
656 AT+RECV  :  Print Last Received Data in Raw Format
657
658 AT+RECVB :  Print Last Received Data in Binary Format      
659
660 AT+SEND  :  Send Text Data      
661
662 AT+SENB  :  Send Hexadecimal Data
663
664
665 (% style="color:#037691" %)** LoRa Network Management :**
666
667 AT+ADR  :  Adaptive Rate
668
669 AT+CLASS  :  LoRa Class(Currently only support class A
670
671 AT+DCS  :  Duty Cycle Setting 
672
673 AT+DR  :  Data Rate (Can Only be Modified after ADR=0)     
674
675 AT+FCD  :  Frame Counter Downlink       
676
677 AT+FCU  :  Frame Counter Uplink   
678
679 AT+JN1DL  :  Join Accept Delay1
680
681 AT+JN2DL  :  Join Accept Delay2
682
683 AT+PNM  :  Public Network Mode   
684
685 AT+RX1DL  :  Receive Delay1      
686
687 AT+RX2DL  :  Receive Delay2      
688
689 AT+RX2DR  :  Rx2 Window Data Rate 
690
691 AT+RX2FQ  :  Rx2 Window Frequency
692
693 AT+TXP  :  Transmit Power
694
695
696 (% style="color:#037691" %)** Information :**
697
698 AT+RSSI  :  RSSI of the Last Received Packet   
699
700 AT+SNR  :  SNR of the Last Received Packet   
701
702 AT+VER  :  Image Version and Frequency Band       
703
704 AT+FDR  :  Factory Data Reset
705
706 AT+PORT  :  Application Port    
707
708 AT+CHS  :  Get or Set Frequency (Unit: Hz) for Single Channel Mode
709
710 AT+CHE  :  Get or Set eight channels mode, Only for US915, AU915, CN470
711
712
713
714 == 3.2  Set Interrupt Mode ==
715
716 Feature, Set Interrupt mode for GPIO_EXIT.
717
718 (% style="color:#037691" %)**Downlink Command: AT+INTMOD**
719
720 [[image:image-20220610174917-9.png]]
721
722
723 (% style="color:#037691" %)**Downlink Command: 0x06**
724
725 Format: Command Code (0x06) followed by 3 bytes.
726
727 (((
728 This means that the interrupt mode of the end node is set to 0x000003=3 (rising edge trigger), and the type code is 06.
729 )))
730
731 * Example 1: Downlink Payload: 06000000 ~/~/ Turn off interrupt mode
732 * Example 2: Downlink Payload: 06000003 ~/~/ Set the interrupt mode to rising edge trigger
733
734
735
736 = 4.  FAQ =
737
738 == 4.1  What is the frequency plan for LDDS20? ==
739
740 LDDS20 use the same frequency as other Dragino products. User can see the detail from this link:  [[Introduction>>doc:Main.End Device Frequency Band.WebHome||anchor="H1.Introduction"]]
741
742
743
744 == 4.2  How to change the LoRa Frequency Bands/Region ==
745
746 You can follow the instructions for [[how to upgrade image>>||anchor="H2.7A0200BFirmwareChangeLog"]].
747 When downloading the images, choose the required image file for download. ​
748
749
750
751 = 5.  Trouble Shooting =
752
753 == 5.1  Why I can’t join TTN V3 in US915 / AU915 bands? ==
754
755 It is due to channel mapping. Please see below link:  [[Frequency band>>doc:Main.LoRaWAN Communication Debug.WebHome||anchor="H2.NoticeofUS9152FCN4702FAU915Frequencyband"]]
756
757
758 == 5.2  AT Command input doesn't work ==
759
760 In the case if user can see the console output but can’t type input to the device. Please check if you already include the (% style="color:green" %)**ENTER**(%%) while sending out the command. Some serial tool doesn’t send (% style="color:green" %)**ENTER**(%%) while press the send key, user need to add ENTER in their string.
761
762 (((
763
764 )))
765
766
767 = 6.  Order Info =
768
769
770 Part Number **:** (% style="color:blue" %)**LDDS20-XX**
771
772
773 (% style="color:blue" %)**XX**(%%)**: **The default frequency band
774
775 * (% style="color:red" %)**AS923 **(%%)**:** LoRaWAN AS923 band
776 * (% style="color:red" %)**AU915 **(%%)**:** LoRaWAN AU915 band
777 * (% style="color:red" %)**EU433 **(%%)**:** LoRaWAN EU433 band
778 * (% style="color:red" %)**EU868 **(%%)**:** LoRaWAN EU868 band
779 * (% style="color:red" %)**KR920 **(%%)**:** LoRaWAN KR920 band
780 * (% style="color:red" %)**US915 **(%%)**:** LoRaWAN US915 band
781 * (% style="color:red" %)**IN865 **(%%)**:**  LoRaWAN IN865 band
782 * (% style="color:red" %)**CN470 **(%%)**:** LoRaWAN CN470 band
783
784
785 = 7. ​ Packing Info =
786
787
788 **Package Includes**:
789
790 * LDDS20 LoRaWAN Liquid Level Sensor x 1
791
792
793 (% style="color:red" %)**Note:**
794
795 (% style="color:red" %)**Ultrasonic coupling paste**(%%) and(% style="color:red" %)** Eproxy AB glue**(%%) are subjected in most shipping way. So the default package doesn’t include it and user needs to purchase locally.
796
797
798 **Dimension and weight**:
799
800 * Device Size: cm
801 * Device Weight: g
802 * Package Size / pcs : cm
803 * Weight / pcs : g
804
805
806 = 8.  ​Support =
807
808 * Support is provided Monday to Friday, from 09:00 to 18:00 GMT+8. Due to different timezones we cannot offer live support. However, your questions will be answered as soon as possible in the before-mentioned schedule.
809 * Provide as much information as possible regarding your enquiry (product models, accurately describe your problem and steps to replicate it etc) and send a mail to [[support@dragino.com>>url:http://../../../../../../D:%5C%E5%B8%82%E5%9C%BA%E8%B5%84%E6%96%99%5C%E8%AF%B4%E6%98%8E%E4%B9%A6%5CLoRa%5CLT%E7%B3%BB%E5%88%97%5Csupport@dragino.com]].