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Version 175.19 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 == 1.7  Precautions ==
208
209 * 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.
210 * 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.
211 * 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.
212
213 == 1.8  Pin mapping and power on ==
214
215
216 [[image:1655257026882-201.png]]
217
218
219
220 = 2.  Configure LDDS20 to connect to LoRaWAN network =
221
222
223 == 2.1  How it works ==
224
225 (((
226 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.
227 )))
228
229 (((
230 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.
231 )))
232
233
234
235 == 2.2  ​Quick guide to connect to LoRaWAN server (OTAA) ==
236
237 (((
238 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.
239 )))
240
241 (((
242 [[image:1655257698953-697.png]]
243 )))
244
245 (((
246 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.
247 )))
248
249 (((
250
251
252 (% style="color:blue" %)**Step 1**(%%): Create a device in TTN with the OTAA keys from LDDS20.
253 )))
254
255 (((
256 Each LDDS20 is shipped with a sticker with the default device keys, user can find this sticker in the box. it looks like below.
257 )))
258
259 [[image:image-20220607170145-1.jpeg]]
260
261
262 (((
263 For OTAA registration, we need to set **APP EUI/ APP KEY/ DEV EUI**. Some server might no need to set APP EUI.
264 )))
265
266 (((
267 Enter these keys in the LoRaWAN Server portal. Below is TTN V3 screen shot:
268 )))
269
270 (((
271
272
273 **Add APP EUI in the application**
274 )))
275
276 [[image:image-20220610161353-4.png]]
277
278 [[image:image-20220610161353-5.png]]
279
280 [[image:image-20220610161353-6.png]]
281
282
283 [[image:image-20220610161353-7.png]]
284
285
286
287 You can also choose to create the device manually.
288
289 [[image:image-20220610161538-8.png]]
290
291
292
293 **Add APP KEY and DEV EUI**
294
295 [[image:image-20220610161538-9.png]]
296
297
298
299 (% style="color:blue" %)**Step 2**(%%):  Power on LDDS20
300
301
302 Put a Jumper on JP2 to power on the device. ( The Switch must be in FLASH position).
303
304 [[image:image-20220615095102-14.png]]
305
306
307
308 (((
309 (% 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.
310 )))
311
312 [[image:1654849068701-275.png]]
313
314
315
316 == 2.3  ​Uplink Payload ==
317
318 (((
319 (((
320 LDDS20 will uplink payload via LoRaWAN with below payload format: 
321
322 Uplink payload includes in total 8 bytes.
323 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).
324 )))
325 )))
326
327 (((
328
329 )))
330
331 (% border="1" cellspacing="10" style="background-color:#ffffcc; width:510px" %)
332 |=(% style="width: 62.5px;" %)(((
333 **Size (bytes)**
334 )))|=(% style="width: 62.5px;" %)**2**|=**2**|=1|=2|=**1**
335 |(% style="width:62.5px" %)**Value**|(% style="width:62.5px" %)[[BAT>>||anchor="H2.3.1A0BatteryInfo"]]|(((
336 [[Distance>>||anchor="H2.3.2A0Distance"]]
337
338 (unit: mm)
339 )))|[[Digital Interrupt (Optional)>>||anchor="H2.3.3A0InterruptPin"]]|(((
340 [[Temperature (Optional )>>||anchor="H2.3.4A0DS18B20Temperaturesensor"]]
341 )))|[[Sensor Flag>>||anchor="H2.3.5A0SensorFlag"]]
342
343 [[image:1654850511545-399.png]]
344
345
346
347 === 2.3.1  Battery Info ===
348
349
350 Check the battery voltage for LDDS20.
351
352 Ex1: 0x0B45 = 2885mV
353
354 Ex2: 0x0B49 = 2889mV
355
356
357
358 === 2.3.2  Distance ===
359
360 (((
361 Get the distance. Flat object range 20mm - 2000mm.
362 )))
363
364 (((
365 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.**
366 )))
367
368 * If the sensor value is 0x0000, it means system doesn't detect ultrasonic sensor.
369 * If the sensor value lower than 0x0014 (20mm), the sensor value will be invalid.
370
371 === 2.3.3  Interrupt Pin ===
372
373 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.
374
375 **Example:**
376
377 0x00: Normal uplink packet.
378
379 0x01: Interrupt Uplink Packet.
380
381
382
383 === 2.3.4  DS18B20 Temperature sensor ===
384
385 This is optional, user can connect external DS18B20 sensor to the +3.3v, 1-wire and GND pin . and this field will report temperature.
386
387 **Example**:
388
389 If payload is: 0105H:  (0105 & FC00 == 0), temp = 0105H /10 = 26.1 degree
390
391 If payload is: FF3FH :  (FF3F & FC00 == 1) , temp = (FF3FH - 65536)/10 = -19.3 degrees.
392
393 (% style="color:red" %)Note: DS18B20 feature is supported in the hardware version > v1.3 which made since early of 2021.
394
395
396
397 === 2.3.5  Sensor Flag ===
398
399 (((
400 0x01: Detect Ultrasonic Sensor
401 )))
402
403 (((
404 0x00: No Ultrasonic Sensor
405 )))
406
407
408
409 === 2.3.6  Decode payload in The Things Network ===
410
411 While using TTN network, you can add the payload format to decode the payload.
412
413
414 [[image:1655261164557-670.png]]
415
416 The payload decoder function for TTN V3 is here:
417
418 (((
419 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/]]
420 )))
421
422
423
424 == 2.4  Downlink Payload ==
425
426 By default, LDDS20 prints the downlink payload to console port.
427
428 [[image:image-20220615100930-15.png]]
429
430
431 **Examples:**
432
433
434 * (% style="color:blue" %)**Set TDC**
435
436 If the payload=0100003C, it means set the END Node's TDC to 0x00003C=60(S), while type code is 01.
437
438 Payload:    01 00 00 1E    TDC=30S
439
440 Payload:    01 00 00 3C    TDC=60S
441
442
443 * (% style="color:blue" %)**Reset**
444
445 If payload = 0x04FF, it will reset the LDDS20
446
447
448 * (% style="color:blue" %)**CFM**
449
450 Downlink Payload: 05000001, Set AT+CFM=1 or 05000000 , set AT+CFM=0
451
452
453
454 == 2.5  ​Show Data in DataCake IoT Server ==
455
456 (((
457 [[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:
458 )))
459
460 (((
461
462 )))
463
464 (((
465 (% style="color:blue" %)**Step 1**(%%)**: Be sure that your device is programmed and properly connected to the network at this time.**
466 )))
467
468 (((
469 (% 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:**
470 )))
471
472
473 [[image:1654592790040-760.png]]
474
475
476 [[image:1654592800389-571.png]]
477
478
479 (% style="color:blue" %)**Step 3**(%%)**: Create an account or log in Datacake.**
480
481 (% style="color:blue" %)**Step 4**(%%)**: Search the LDDS75 and add DevEUI.(% style="color:red" %)(Note: LDDS20 use same payload as LDDS75)(%%)**
482
483 [[image:1654851029373-510.png]]
484
485
486 After added, the sensor data arrive TTN V3, it will also arrive and show in Datacake.
487
488 [[image:image-20220610165129-11.png||height="595" width="1088"]]
489
490
491
492 == 2.6  LED Indicator ==
493
494 The LDDS20 has an internal LED which is to show the status of different state.
495
496
497 * Blink once when device power on.
498 * The device detects the sensor and flashes 5 times.
499 * Solid ON for 5 seconds once device successful Join the network.
500 * Blink once when device transmit a packet.
501
502 == 2.7  ​Firmware Change Log ==
503
504
505 (((
506 **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/]]
507 )))
508
509 (((
510
511 )))
512
513 (((
514 **Firmware Upgrade Method:  [[Firmware Upgrade Instruction>>doc:Main.Firmware Upgrade Instruction for STM32 base products.WebHome]]**
515 )))
516
517
518
519 == 2.8  Battery Analysis ==
520
521
522
523
524 === 2.8.1  Battery Type ===
525
526 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.
527
528
529 The battery related documents as below:
530
531 * (((
532 [[Battery Dimension>>https://www.dragino.com/downloads/index.php?dir=datasheet/Battery/ER26500/]],
533 )))
534 * (((
535 [[Lithium-Thionyl Chloride Battery  datasheet>>https://www.dragino.com/downloads/index.php?dir=datasheet/Battery/ER26500/]],
536 )))
537 * (((
538 [[Lithium-ion Battery-Capacitor datasheet>>https://www.dragino.com/downloads/index.php?dir=datasheet/Battery/ER26500/]]
539 )))
540
541 [[image:image-20220615102527-16.png]]
542
543
544
545 == 2.8.2  Battery Note ==
546
547 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.
548
549
550
551 === 2.8.3  Replace the battery ===
552
553 (((
554 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.
555 )))
556
557 (((
558
559 )))
560
561 (((
562 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)
563 )))
564
565
566
567 == 2.8.4  Battery Life Analyze ==
568
569 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:
570
571 [[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]]
572
573
574
575 = 3.  Using the AT Commands =
576
577 (((
578 (((
579
580 )))
581 )))
582
583 == 3.1  Access AT Commands ==
584
585 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.
586
587
588 [[image:image-20220610172924-4.png||height="483" width="988"]]
589
590
591 Or if you have below board, use below connection:
592
593
594 [[image:image-20220610172924-5.png]]
595
596
597 (((
598 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:
599 )))
600
601
602 [[image:image-20220610172924-6.png||height="601" width="860"]]
603
604 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/]].
605
606
607 AT+<CMD>?  :  Help on <CMD>
608
609 AT+<CMD>  :  Run <CMD>
610
611 AT+<CMD>=<value>  :  Set the value
612
613 AT+<CMD>=?  :  Get the value
614
615
616 (% style="color:#037691" %)** General Commands :**     
617
618 AT  :  Attention       
619
620 AT?  :  Short Help     
621
622 ATZ :  MCU Reset    
623
624 AT+TDC :  Application Data Transmission Interval 
625
626
627 (% style="color:#037691" %)** Keys, IDs and EUIs management :**
628
629 AT+APPEUI  :  Application EUI      
630
631 AT+APPKEY  :  Application Key     
632
633 AT+APPSKEY  :  Application Session Key
634
635 AT+DADDR :  Device Address     
636
637 AT+DEUI :  Device EUI     
638
639 AT+NWKID  :  Network ID (You can enter this command change only after successful network connection) 
640
641 AT+NWKSKEY  : Network Session Key Joining and sending date on LoRa network  
642
643 AT+CFM :  Confirm Mode       
644
645 AT+CFS :  Confirm Status       
646
647 AT+JOIN  :  Join LoRa? Network       
648
649 AT+NJM  :  LoRa? Network Join Mode    
650
651 AT+NJS  :  LoRa? Network Join Status    
652
653 AT+RECV  :  Print Last Received Data in Raw Format
654
655 AT+RECVB :  Print Last Received Data in Binary Format      
656
657 AT+SEND  :  Send Text Data      
658
659 AT+SENB  :  Send Hexadecimal Data
660
661
662 (% style="color:#037691" %)** LoRa Network Management :**
663
664 AT+ADR  :  Adaptive Rate
665
666 AT+CLASS  :  LoRa Class(Currently only support class A
667
668 AT+DCS  :  Duty Cycle Setting 
669
670 AT+DR  :  Data Rate (Can Only be Modified after ADR=0)     
671
672 AT+FCD  :  Frame Counter Downlink       
673
674 AT+FCU  :  Frame Counter Uplink   
675
676 AT+JN1DL  :  Join Accept Delay1
677
678 AT+JN2DL  :  Join Accept Delay2
679
680 AT+PNM  :  Public Network Mode   
681
682 AT+RX1DL  :  Receive Delay1      
683
684 AT+RX2DL  :  Receive Delay2      
685
686 AT+RX2DR  :  Rx2 Window Data Rate 
687
688 AT+RX2FQ  :  Rx2 Window Frequency
689
690 AT+TXP  :  Transmit Power
691
692
693 (% style="color:#037691" %)** Information :**
694
695 AT+RSSI  :  RSSI of the Last Received Packet   
696
697 AT+SNR  :  SNR of the Last Received Packet   
698
699 AT+VER  :  Image Version and Frequency Band       
700
701 AT+FDR  :  Factory Data Reset
702
703 AT+PORT  :  Application Port    
704
705 AT+CHS  :  Get or Set Frequency (Unit: Hz) for Single Channel Mode
706
707 AT+CHE  :  Get or Set eight channels mode, Only for US915, AU915, CN470
708
709
710
711 == 3.2  Set Interrupt Mode ==
712
713 Feature, Set Interrupt mode for GPIO_EXIT.
714
715 (% style="color:#037691" %)**Downlink Command: AT+INTMOD**
716
717 [[image:image-20220610174917-9.png]]
718
719
720 (% style="color:#037691" %)**Downlink Command: 0x06**
721
722 Format: Command Code (0x06) followed by 3 bytes.
723
724 (((
725 This means that the interrupt mode of the end node is set to 0x000003=3 (rising edge trigger), and the type code is 06.
726 )))
727
728 * Example 1: Downlink Payload: 06000000 ~/~/ Turn off interrupt mode
729 * Example 2: Downlink Payload: 06000003 ~/~/ Set the interrupt mode to rising edge trigger
730
731
732
733 = 4.  FAQ =
734
735 == 4.1  What is the frequency plan for LDDS20? ==
736
737 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"]]
738
739
740
741 == 4.2  How to change the LoRa Frequency Bands/Region ==
742
743 You can follow the instructions for [[how to upgrade image>>||anchor="H2.7A0200BFirmwareChangeLog"]].
744 When downloading the images, choose the required image file for download. ​
745
746
747
748 = 5.  Trouble Shooting =
749
750 == 5.1  Why I can’t join TTN V3 in US915 / AU915 bands? ==
751
752 It is due to channel mapping. Please see below link:  [[Frequency band>>doc:Main.LoRaWAN Communication Debug.WebHome||anchor="H2.NoticeofUS9152FCN4702FAU915Frequencyband"]]
753
754
755 == 5.2  AT Command input doesn't work ==
756
757 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.
758
759 (((
760
761 )))
762
763
764 = 6.  Order Info =
765
766
767 Part Number **:** (% style="color:blue" %)**LDDS20-XX**
768
769
770 (% style="color:blue" %)**XX**(%%)**: **The default frequency band
771
772 * (% style="color:red" %)**AS923 **(%%)**:** LoRaWAN AS923 band
773 * (% style="color:red" %)**AU915 **(%%)**:** LoRaWAN AU915 band
774 * (% style="color:red" %)**EU433 **(%%)**:** LoRaWAN EU433 band
775 * (% style="color:red" %)**EU868 **(%%)**:** LoRaWAN EU868 band
776 * (% style="color:red" %)**KR920 **(%%)**:** LoRaWAN KR920 band
777 * (% style="color:red" %)**US915 **(%%)**:** LoRaWAN US915 band
778 * (% style="color:red" %)**IN865 **(%%)**:**  LoRaWAN IN865 band
779 * (% style="color:red" %)**CN470 **(%%)**:** LoRaWAN CN470 band
780
781
782 = 7. ​ Packing Info =
783
784
785 **Package Includes**:
786
787 * LDDS20 LoRaWAN Liquid Level Sensor x 1
788
789
790 (% style="color:red" %)**Note:**
791
792 (% 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.
793
794
795 **Dimension and weight**:
796
797 * Device Size: cm
798 * Device Weight: g
799 * Package Size / pcs : cm
800 * Weight / pcs : g
801
802
803 = 8.  ​Support =
804
805 * 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.
806 * 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]].