RS485-BL – Waterproof RS485 to LoRaWAN Converter

The Dragino RS485-BL is a **RS485 / UART to LoRaWAN Converter** for Internet of Things solutions. User can connect RS485 or UART sensor to RS485-BL converter, and configure RS485-BL to periodically read sensor data and upload via LoRaWAN network to IoT server.

27

)))

28

29

(((

30

RS485-BL can interface to RS485 sensor, 3.3v/5v UART sensor or interrupt sensor. RS485-BL provides **a 3.3v output** and** a 5v output** to power external sensors. Both output voltages are controllable to minimize the total system power consumption.

)))

(((

RS485-BL is IP67 **waterproof** and powered by **8500mAh Li-SOCI2 battery**, it is designed for long term use for several years.

)))

(((

RS485-BL runs standard **LoRaWAN 1.0.3 in Class A**. It can reach long transfer range and easy to integrate with LoRaWAN compatible gateway and IoT server.

)))

(((

For data uplink, RS485-BL sends user-defined commands to RS485 devices and gets the return from the RS485 devices. RS485-BL will process these returns data according to user-define rules to get the final payload and upload to LoRaWAN server.

)))

(((

For data downlink, RS485-BL runs in LoRaWAN Class A. When there is downlink commands from LoRaWAN server, RS485-BL will forward the commands from LoRaWAN server to RS485 devices.

)))

(((

Each RS485-BL pre-load with a set of unique keys for LoRaWAN registration, register these keys to LoRaWAN server and it will auto connect after power on.

51

)))

52

53

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image002.png]]

54

55

== 1.2 Specifications ==

**Hardware System:**

* STM32L072CZT6 MCU

* SX1276/78 Wireless Chip

61

* Power Consumption (exclude RS485 device):

** Idle: 6uA@3.3v

*

** 20dB Transmit: 130mA@3.3v

66

67

68

**Interface for Model:**

69

70

* 1 x RS485 Interface

71

* 1 x TTL Serial , 3.3v or 5v.

72

* 1 x I2C Interface, 3.3v or 5v.

73

* 1 x one wire interface

74

* 1 x Interrupt Interface

75

* 1 x Controllable 5V output, max

**LoRa Spec:**

* Frequency Range:

** Band 1 (HF): 862 ~~ 1020 Mhz

82

** Band 2 (LF): 410 ~~ 528 Mhz

83

* 168 dB maximum link budget.

84

* +20 dBm - 100 mW constant RF output vs.

85

* Programmable bit rate up to 300 kbps.

86

* High sensitivity: down to -148 dBm.

87

* Bullet-proof front end: IIP3 = -12.5 dBm.

88

* Excellent blocking immunity.

89

* Fully integrated synthesizer with a resolution of 61 Hz.

90

* LoRa modulation.

91

* Built-in bit synchronizer for clock recovery.

92

* Preamble detection.

93

* 127 dB Dynamic Range RSSI.

94

* Automatic RF Sense and CAD with ultra-fast AFC.

*

*1. Features

* LoRaWAN Class A & Class C protocol (default Class A)

100

* Frequency Bands: CN470/EU433/KR920/US915/EU868/AS923/AU915/IN865/RU864

101

* AT Commands to change parameters

102

* Remote configure parameters via LoRaWAN Downlink

103

* Firmware upgradable via program port

104

* Support multiply RS485 devices by flexible rules

105

* Support Modbus protocol

106

* Support Interrupt uplink

*

*1. Applications

* Smart Buildings & Home Automation

112

* Logistics and Supply Chain Management

* Smart Metering

* Smart Agriculture

* Smart Cities

* Smart Factory

1.

11. Firmware Change log

121

122

[[RS485-BL Image files – Download link and Change log>>url:http://www.dragino.com/downloads/index.php?dir=LoRa_End_Node/RS485-BL/Firmware/]]

1.

11. Hardware Change log

v1.4

~1. Change Power IC to TPS22916

v1.3

~1. Change JP3 from KF350-8P to KF350-11P, Add one extra interface for I2C and one extra interface for one-wire

v1.2

Release version

1. Pin mapping and Power ON Device

148

149

The RS485-BL is powered on by 8500mAh battery. To save battery life, RS485-BL is shipped with power off. User can put the jumper to power on RS485-BL.

150

151

152

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image003.png]]

The Left TXD and RXD are TTL interface for external sensor. TTL level is controlled by 3.3/5v Jumper.

1. Operation Mode

11. How it works?

The RS485-BL is configured as LoRaWAN OTAA Class A mode by default. It has OTAA keys to join network. To connect a local LoRaWAN network, user just need to input the OTAA keys in the network server and power on the RS485-BL. It will auto join the network via OTAA.

1.

11. Example to join LoRaWAN network

171

172

Here shows an example for how to join the TTN V3 Network. Below is the network structure, we use [[LG308>>url:http://www.dragino.com/products/lora-lorawan-gateway/item/140-lg308.html]] as LoRaWAN gateway here.

173

174

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image004.png]]

175

176

177

The RS485-BL in this example connected to two RS485 devices for demonstration, user can connect to other RS485 devices via the same method.

178

179

180

The LG308 is already set to connect to [[TTN V3 network >>url:https://www.thethingsnetwork.org/]]. So what we need to now is only configure the TTN V3:

181

182

**Step 1**: Create a device in TTN V3 with the OTAA keys from RS485-BL.

183

184

Each RS485-BL is shipped with a sticker with unique device EUI:

185

186

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image005.png]]

User can enter this key in their LoRaWAN Server portal. Below is TTN V3 screen shot:

192

193

Add APP EUI in the application.

194

195

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image006.png]]

196

197

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image007.png]]

198

199

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image008.png]]

200

201

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image009.png]]

You can also choose to create the device manually.

|(((

)))

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image010.png]]

228

229

Add APP KEY and DEV EUI

230

231

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image011.png]]

232

233

234

**Step 2**: Power on RS485-BL and it will auto join to the TTN V3 network. After join success, it will start to upload message to TTN V3 and user can see in the panel.

235

236

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image012.png]]

1.

11. Configure Commands to read data

243

244

There are plenty of RS485 and TTL level devices in the market and each device has different command to read the valid data. To support these devices in flexible, RS485-BL supports flexible command set. User can use [[AT Commands or LoRaWAN Downlink>>path:#AT_COMMAND]] Command to configure how RS485-BL should read the sensor and how to handle the return from RS485 or TTL sensors.

1.

11.

111. Configure UART settings for RS485 or TTL communication

250

251

RS485-BL can connect to either RS485 sensors or TTL sensor. User need to specify what type of sensor need to connect.

252

253

1. RS485-MODBUS mode:

254

255

AT+MOD=1 ~/~/ Support RS485-MODBUS type sensors. User can connect multiply RS485 , Modbus sensors to the A / B pins.

1. TTL mode:

AT+MOD=2 ~/~/ Support TTL Level sensors, User can connect one TTL Sensor to the TXD/RXD/GND pins.

261

262

263

RS485-BL default UART settings is **9600, no parity, stop bit 1**. If the sensor has a different settings, user can change the RS485-BL setting to match.

264

265

266

|**AT Commands**|**Description**|**Example**

267

|AT+BAUDR|Set the baud rate (for RS485 connection). Default Value is: 9600.|(((

268

AT+BAUDR=9600

269

270

Options: (1200,2400,4800,14400,19200,115200)

271

)))

272

|AT+PARITY|(((

273

Set UART parity (for RS485 connection)

274

275

Default Value is: no parity.

)))|(((

AT+PARITY=0

Option: 0: no parity, 1: odd parity, 2: even parity

280

)))

281

|AT+STOPBIT|(((

282

Set serial stopbit (for RS485 connection)

283

284

Default Value is: 1bit.

285

)))|(((

286

AT+STOPBIT=0 for 1bit

287

288

AT+STOPBIT=1 for 1.5 bit

289

290

AT+STOPBIT=2 for 2 bits

)))

1.

11.

111. Configure sensors

300

301

Some sensors might need to configure before normal operation. User can configure such sensor via PC or through RS485-BL AT Commands AT+CFGDEV.

302

303

304

When user issue an AT+CFGDEV command, Each AT+CFGDEV equals to send a command to the RS485 or TTL sensors. This command will only run when user input it and won’t run during each sampling.

305

306

|**AT Commands**|**Description**|**Example**

307

|AT+CFGDEV|(((

308

This command is used to configure the RS485/TTL devices; they won’t be used during sampling.

309

310

AT+CFGDEV=xx xx xx xx xx xx xx xx xx xx xx xx,m

311

312

m: 0: no CRC, 1: add CRC-16/MODBUS in the end of this command

313

)))|AT+CFGDEV=xx xx xx xx xx xx xx xx xx xx xx xx,m

314

315

Detail of AT+CFGDEV command see [[AT+CFGDEV detail>>path:#AT_CFGDEV]].

1.

11.

111. Configure read commands for each sampling

324

325

RS485-BL is a battery powered device; it will sleep most of time. And wake up on each period and read RS485 / TTL sensor data and uplink.

326

327

328

During each sampling, we need to confirm what commands we need to send to the sensors to read data. After the RS485/TTL sensors send back the value, it normally includes some bytes and we only need a few from them for a shorten payload.

329

330

331

To save the LoRaWAN network bandwidth, we might need to read data from different sensors and combine their valid value into a short payload.

332

333

334

This section describes how to achieve above goals.

335

336

337

During each sampling, the RS485-BL can support 15 commands to read sensors. And combine the return to one or several uplink payloads.

338

339

340

**Command from RS485-BL to Sensor:**

341

342

RS485-BL can send out pre-set max 15 strings via **AT+COMMAD1**, **ATCOMMAND2**,…, to **AT+COMMANDF** . All commands are of same grammar.

343

344

345

**Handle return from sensors to RS485-BL**:

346

347

After RS485-BL send out a string to sensor, RS485-BL will wait for the return from RS485 or TTL sensor. And user can specify how to handle the return, by **AT+DATACUT or AT+SEARCH commands**

* **AT+DATACUT**

When the return value from sensor have fix length and we know which position the valid value we should get, we can use AT+DATACUT command.

* **AT+SEARCH**

When the return value from sensor is dynamic length and we are not sure which bytes the valid data is, instead, we know what value the valid value following. We can use AT+SEARCH to search the valid value in the return string.

358

359

360

**Define wait timeout:**

361

362

Some RS485 device might has longer delay on reply, so user can use AT+CMDDL to set the timeout for getting reply after the RS485 command is sent. For example, AT+CMDDL1=1000 to send the open time to 1000ms

363

364

365

After we got the valid value from each RS485 commands, we need to combine them together with the command **AT+DATAUP**.

**Examples:**

Below are examples for the how above AT Commands works.

371

372

373

**AT+COMMANDx : **This command will be sent to RS485/TTL devices during each sampling, Max command length is 14 bytes. The grammar is:

374

375

|(((

376

**AT+COMMANDx=xx xx xx xx xx xx xx xx xx xx xx xx,m**

377

378

**xx xx xx xx xx xx xx xx xx xx xx xx: The RS485 command to be sent**

379

380

**m: 0: no CRC, 1: add CRC-16/MODBUS in the end of this command**

381

)))

382

383

For example, if we have a RS485 sensor. The command to get sensor value is: 01 03 0B B8 00 02 46 0A. Where 01 03 0B B8 00 02 is the Modbus command to read the register 0B B8 where stored the sensor value. The 46 0A is the CRC-16/MODBUS which calculate manually.

384

385

In the RS485-BL, we should use this command AT+COMMAND1=01 03 0B B8 00 02,1 for the same.

386

387

388

**AT+SEARCHx**: This command defines how to handle the return from AT+COMMANDx.

389

390

|(((

391

**AT+SEARCHx=aa,xx xx xx xx xx**

392

393

* **aa: 1: prefix match mode; 2: prefix and suffix match mode**

394

* **xx xx xx xx xx: match string. Max 5 bytes for prefix and 5 bytes for suffix**

)))

Examples:

1. For a return string from AT+COMMAND1: 16 0c 1e 56 34 2e 30 58 5f 36 41 30 31 00 49

402

403

If we set AT+SEARCH1=1,1E 56 34. (max 5 bytes for prefix)

404

405

The valid data will be all bytes after 1E 56 34 , so it is 2e 30 58 5f 36 41 30 31 00 49

406

407

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image013.png]]

408

409

410

1. For a return string from AT+COMMAND1: 16 0c 1e 56 34 2e 30 58 5f 36 41 30 31 00 49

411

412

If we set AT+SEARCH1=2, 1E 56 34+31 00 49

413

414

Device will search the bytes between 1E 56 34 and 31 00 49. So it is 2e 30 58 5f 36 41 30

415

416

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image014.png]]

417

418

419

**AT+DATACUTx : **This command defines how to handle the return from AT+COMMANDx, max return length is 45 bytes.

420

421

|(((

422

**AT+DATACUTx=a,b,c**

423

424

* **a: length for the return of AT+COMMAND**

425

* **b:1: grab valid value by byte, max 6 bytes. 2: grab valid value by bytes section, max 3 sections.**

426

* **c: define the position for valid value. **

)))

Examples:

* Grab bytes:

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image015.png]]

* Grab a section.

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image016.png]]

438

439

* Grab different sections.

440

441

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image017.png]]

Note:

AT+SEARCHx and AT+DATACUTx can be used together, if both commands are set, RS485-BL will first process AT+SEARCHx on the return string and get a temporary string, and then process AT+DATACUTx on this temporary string to get the final payload. In this case, AT+DATACUTx need to set to format AT+DATACUTx=0,xx,xx where the return bytes set to 0.

Example:

AT+COMMAND1=11 01 1E D0,0

451

452

AT+SEARCH1=1,1E 56 34

AT+DATACUT1=0,2,1~~5

Return string from AT+COMMAND1: 16 0c 1e 56 34 2e 30 58 5f 36 41 30 31 00 49

457

458

String after SEARCH command: 2e 30 58 5f 36 41 30 31 00 49

459

460

Valid payload after DataCUT command: 2e 30 58 5f 36

461

462

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image018.png]]

1.

11.

111. Compose the uplink payload

470

471

Through AT+COMMANDx and AT+DATACUTx we got valid value from each RS485 commands, Assume these valid value are RETURN1, RETURN2, .., to RETURNx. The next step is how to compose the LoRa Uplink Payload by these RETURNs. The command is **AT+DATAUP.**

472

473

474

**Examples: AT+DATAUP=0**

475

476

Compose the uplink payload with value returns in sequence and send with **A SIGNLE UPLINK**.

Final Payload is

Battery Info+PAYVER + VALID Value from RETURN1 + Valid Value from RETURN2 + … + RETURNx

481

482

Where PAYVER is defined by AT+PAYVER, below is an example screen shot.

483

484

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image019.png]]

**Examples: AT+DATAUP=1**

489

490

Compose the uplink payload with value returns in sequence and send with **Multiply UPLINKs**.

Final Payload is

Battery Info+PAYVER + PAYLOAD COUNT + PAYLOAD# + DATA

495

496

1. Battery Info (2 bytes): Battery voltage

497

1. PAYVER (1 byte): Defined by AT+PAYVER

498

1. PAYLOAD COUNT (1 byte): Total how many uplinks of this sampling.

499

1. PAYLOAD# (1 byte): Number of this uplink. (from 0,1,2,3…,to PAYLOAD COUNT)

500

1. DATA: Valid value: max 6 bytes(US915 version here, [[Notice*!>>path:#max_byte]]) for each uplink so each uplink <= 11 bytes. For the last uplink, DATA will might less than 6 bytes

501

502

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image020.png]]

503

504

505

So totally there will be 3 uplinks for this sampling, each uplink includes 6 bytes DATA

506

507

DATA1=RETURN1 Valid Value = 20 20 0a 33 90 41

508

509

DATA2=1^^st^^ ~~ 6^^th^^ byte of Valid value of RETURN10= 02 aa 05 81 0a 20

510

511

DATA3=7^^th^^ ~~ 11^^th^^ bytes of Valid value of RETURN10 = 20 20 20 2d 30

Below are the uplink payloads:

516

517

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image021.png]]

518

519

520

Notice: the Max bytes is according to the max support bytes in different Frequency Bands for lowest SF. As below:

521

522

~* For AU915/AS923 bands, if UplinkDwell time=0, max 51 bytes for each uplink ( so 51 -5 = 46 max valid date)

523

524

* For AU915/AS923 bands, if UplinkDwell time=1, max 11 bytes for each uplink ( so 11 -5 = 6 max valid date).

525

526

* For US915 band, max 11 bytes for each uplink ( so 11 -5 = 6 max valid date).

527

528

~* For all other bands: max 51 bytes for each uplink ( so 51 -5 = 46 max valid date).

1.

11.

111. Uplink on demand

535

536

Except uplink periodically, RS485-BL is able to uplink on demand. The server sends downlink command to RS485-BL and RS485 will uplink data base on the command.

537

538

Downlink control command:

539

540

[[0x08 command>>path:#downlink_08]]: Poll an uplink with current command set in RS485-BL.

541

542

[[0xA8 command>>path:#downlink_A8]]: Send a command to RS485-BL and uplink the output from sensors.

1.

11.

111. Uplink on Interrupt

549

550

Put the interrupt sensor between 3.3v_out and GPIO ext.[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image022.png]]

551

552

AT+INTMOD=0 Disable Interrupt

553

554

AT+INTMOD=1 Interrupt trigger by rising or falling edge.

555

556

AT+INTMOD=2 Interrupt trigger by falling edge. ( Default Value)

557

558

AT+INTMOD=3 Interrupt trigger by rising edge.

1.

11. Uplink Payload

|**Size(bytes)**|**2**|**1**|**Length depends on the return from the commands**

|Value|(((

Battery(mV)

&

Interrupt _Flag

)))|(((

PAYLOAD_VER

)))|If the valid payload is too long and exceed the maximum support payload length in server, server will show payload not provided in the LoRaWAN server.

577

578

Below is the decoder for the first 3 bytes. The rest bytes are dynamic depends on different RS485 sensors.

579

580

581

function Decoder(bytes, port) {

582

583

~/~/Payload Formats of RS485-BL Deceive

return {

~/~/Battery,units:V

BatV:((bytes[0]<<8 | bytes[1])&0x7fff)/1000,

~/~/GPIO_EXTI

EXTI_Trigger:(bytes[0] & 0x80)? "TRUE":"FALSE",

594

595

~/~/payload of version

Pay_ver:bytes[2],

};

}

TTN V3 uplink screen shot.

610

611

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image023.png]]

612

613

1.

614

11. Configure RS485-BL via AT or Downlink

615

616

User can configure RS485-BL via [[AT Commands >>path:#_Using_the_AT]]or LoRaWAN Downlink Commands

617

618

There are two kinds of Commands:

619

620

* **Common Commands**: They should be available for each sensor, such as: change uplink interval, reset device. For firmware v1.3, user can find what common commands it supports: http:~/~/wiki.dragino.com/index.php?title=End_Device_AT_Commands_and_Downlink_Commands

621

622

* **Sensor Related Commands**: These commands are special designed for RS485-BL. User can see these commands below:

1.

11.

111. Common Commands:

628

629

630

They should be available for each of Dragino Sensors, such as: change uplink interval, reset device. For firmware v1.3, user can find what common commands it supports: [[http:~~/~~/wiki.dragino.com/index.php?title=End_Device_AT_Commands_and_Downlink_Commands>>url:http://wiki.dragino.com/index.php?title=End_Device_AT_Commands_and_Downlink_Commands]]

1.

11.

111. Sensor related commands:

636

637

638

==== Choose Device Type (RS485 or TTL) ====

639

640

RS485-BL can connect to either RS485 sensors or TTL sensor. User need to specify what type of sensor need to connect.

* AT Command

**AT+MOD=1** ~/~/ Set to support RS485-MODBUS type sensors. User can connect multiply RS485 , Modbus sensors to the A / B pins.

645

646

**AT+MOD=2** ~/~/ Set to support TTL Level sensors, User can connect one TTL Sensor to the TXD/RXD/GND pins.

* Downlink Payload

**0A aa** à same as AT+MOD=aa

==== [[RS485 Debug Command>>path:#downlink_A8]] (AT+CFGDEV) ====

656

657

This command is used to configure the RS485 or TTL sensors; they won’t be used during sampling.

* AT Command

AT+CFGDEV=xx xx xx xx xx xx xx xx xx xx xx xx,m

662

663

m: 0: no CRC; 1: add CRC-16/MODBUS in the end of this command.

* Downlink Payload

Format: A8 MM NN XX XX XX XX YY

Where:

* MM: 1: add CRC-16/MODBUS ; 0: no CRC

674

* NN: The length of RS485 command

675

* XX XX XX XX: RS485 command total NN bytes

676

* YY: How many bytes will be uplink from the return of this RS485 command, if YY=0, RS485-BL will execute the downlink command without uplink; if YY>0, RS485-BL will uplink total YY bytes from the output of this RS485 command

**Example 1:**

To connect a Modbus Alarm with below commands.

682

683

* The command to active alarm is: 0A 05 00 04 00 01 4C B0. Where 0A 05 00 04 00 01 is the Modbus command to read the register 00 40 where stored the DI status. The 4C B0 is the CRC-16/MODBUS which calculate manually.

684

685

* The command to deactivate alarm is: 0A 05 00 04 00 00 8D 70. Where 0A 05 00 04 00 00 is the Modbus command to read the register 00 40 where stored the DI status. The 8D 70 is the CRC-16/MODBUS which calculate manually.

686

687

So if user want to use downlink command to control to RS485 Alarm, he can use:

688

689

**A8 01 06 0A 05 00 04 00 01 00**: to activate the RS485 Alarm

690

691

**A8 01 06 0A 05 00 04 00 00 00**: to deactivate the RS485 Alarm

692

693

A8 is type code and 01 means add CRC-16/MODBUS at the end, the 3^^rd^^ byte is 06, means the next 6 bytes are the command to be sent to the RS485 network, the final byte 00 means this command don’t need to acquire output.

**Example 2:**

Check TTL Sensor return:

699

700

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image024.png]]

==== Set Payload version ====

706

707

This is the first byte of the uplink payload. RS485-BL can connect to different sensors. User can set the PAYVER field to tell server how to decode the current payload.

* AT Command:

AT+PAYVER: Set PAYVER field = 1

* Downlink Payload:

0xAE 01 à Set PAYVER field = 0x01

717

718

0xAE 0F à Set PAYVER field = 0x0F

719

720

721

==== Set RS485 Sampling Commands ====

722

723

AT+COMMANDx, AT+DATACUTx and AT+SEARCHx

724

725

These three commands are used to configure how the RS485-BL polling data from Modbus device. Detail of usage please see : [[polling RS485 device>>path:#polling_485]].

* AT Command:

AT+COMMANDx: Configure RS485 read command to sensor.

731

732

AT+DATACUTx: Configure how to handle return from RS485 devices.

733

734

AT+SEARCHx: Configure search command

* Downlink Payload:

0xAF downlink command can be used to set AT+COMMANDx or AT+DATACUTx.

740

741

Note: if user use AT+COMMANDx to add a new command, he also need to send AT+DATACUTx downlink.

742

743

Format: AF MM NN LL XX XX XX XX YY

Where:

* MM: the ATCOMMAND or AT+DATACUT to be set. Value from 01 ~~ 0F,

748

* NN: 0: no CRC; 1: add CRC-16/MODBUS ; 2: set the AT+DATACUT value.

749

* LL: The length of AT+COMMAND or AT+DATACUT command

750

* XX XX XX XX: AT+COMMAND or AT+DATACUT command

751

* YY: If YY=0, RS485-BL will execute the downlink command without uplink; if YY=1, RS485-BL will execute an uplink after got this command.

Example:

**AF 03 01 06 0A 05 00 04 00 01 00**: Same as AT+COMMAND3=0A 05 00 04 00 01,1

756

757

**AF 03 02 06 10 01 05 06 09 0A 00**: Same as AT+DATACUT3=**16**,**1**,**5+6+9+10**

758

759

**AF 03 02 06 0B 02 05 07 08 0A 00**: Same as AT+DATACUT3=**11**,**2**,**5~~7+8~~10**

760

761

762

0xAB downlink command can be used for set AT+SEARCHx

763

764

Example: **AB aa 01 03 xx xx xx** (03 here means there are total 3 bytes after 03) So

765

766

* AB aa 01 03 xx xx xx same as AT+SEARCHaa=1,xx xx xx

767

* AB aa 02 03 xx xx xx 02 yy yy(03 means there are 3 bytes after 03, they are xx xx xx;02 means there are 2 bytes after 02, they are yy yy) so the commands

768

769

**AB aa 02 03 xx xx xx 02 yy yy** same as **AT+SEARCHaa=2,xx xx xx+yy yy**

770

771

772

==== Fast command to handle MODBUS device ====

773

774

AT+MBFUN is valid since v1.3 firmware version. The command is for fast configure to read Modbus devices. It is only valid for the devices which follow the [[MODBUS-RTU protocol>>url:https://www.modbustools.com/modbus.html]].

775

776

This command is valid since v1.3 firmware version

777

778

779

AT+MBFUN has only two value:

780

781

* AT+MBFUN=1: Enable Modbus reading. And get response base on the MODBUS return

782

783

AT+MBFUN=1, device can auto read the Modbus function code: 01, 02, 03 or 04. AT+MBFUN has lower priority vs AT+DATACUT command. If AT+DATACUT command is configured, AT+MBFUN will be ignore.

784

785

* AT+MBFUN=0: Disable Modbus fast reading.

Example:

* AT+MBFUN=1 and AT+DATACUT1/AT+DATACUT2 are not configure (0,0,0).

791

* AT+COMMAND1= 01 03 00 10 00 08,1 ~-~-> read slave address 01 , function code 03, start address 00 01, quantity of registers 00 08.

792

* AT+COMMAND2= 01 02 00 40 00 10,1 ~-~-> read slave address 01 , function code 02, start address 00 40, quantity of inputs 00 10.

793

794

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image025.png]]

795

796

797

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image026.png]]

* Downlink Commands:

A9 aa -à Same as AT+MBFUN=aa

803

804

805

==== RS485 command timeout ====

806

807

Some Modbus device has slow action to send replies. This command is used to configure the RS485-BL to use longer time to wait for their action.

808

809

Default value: 0, range: 0 ~~ 5 seconds

* AT Command:

AT+CMDDLaa=hex(bb cc)

Example:

**AT+CMDDL1=1000** to send the open time to 1000ms

* Downlink Payload:

0x AA aa bb cc

Same as: AT+CMDDLaa=hex(bb cc)

Example:

0xAA 01 03 E8 à Same as **AT+CMDDL1=1000 ms**

830

831

832

==== [[Uplink>>path:#downlink_A8]] payload mode ====

833

834

Define to use one uplink or multiple uplinks for the sampling.

835

836

The use of this command please see: [[Compose Uplink payload>>path:#DataUP]]

* AT Command:

AT+DATAUP=0

AT+DATAUP=1

* Downlink Payload:

0xAD 00 à Same as AT+DATAUP=0

848

849

0xAD 01 à Same as AT+DATAUP=1

850

851

852

==== Manually trigger an Uplink ====

853

854

Ask device to send an uplink immediately.

* Downlink Payload:

0x08 FF, RS485-BL will immediately send an uplink.

859

860

861

==== Clear RS485 Command ====

862

863

The AT+COMMANDx and AT+DATACUTx settings are stored in special location, user can use below command to clear them.

* AT Command:

**AT+CMDEAR=mm,nn** mm: start position of erase ,nn: stop position of erase

869

870

Etc. AT+CMDEAR=1,10 means erase AT+COMMAND1/AT+DATACUT1 to AT+COMMAND10/AT+DATACUT10

871

872

Example screen shot after clear all RS485 commands.

The uplink screen shot is:

877

878

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image023.png]]

* Downlink Payload:

0x09 aa bb same as AT+CMDEAR=aa,bb

884

885

886

==== Set Serial Communication Parameters ====

887

888

Set the Rs485 serial communication parameters:

* AT Command:

Set Baud Rate:

AT+BAUDR=9600 ~/~/ Options: (1200,2400,4800,14400,19200,115200)

Set UART parity

AT+PARITY=0 ~/~/ Option: 0: no parity, 1: odd parity, 2: even parity

Set STOPBIT

AT+STOPBIT=0 ~/~/ Option: 0 for 1bit; 1 for 1.5 bit ; 2 for 2 bits

* Downlink Payload:

A7 01 aa bb: Same AT+BAUDR=hex(aa bb)*100

Example:

* A7 01 00 60 same as AT+BAUDR=9600

914

* A7 01 04 80 same as AT+BAUDR=115200

915

916

917

A7 02 aa: Same as AT+PARITY=aa (aa value: 00 , 01 or 02)

918

919

A7 03 aa: Same as AT+STOPBIT=aa (aa value: 00 , 01 or 02)

920

921

922

==== Control output power duration ====

923

924

User can set the output power duration before each sampling.

* AT Command:

Example:

AT+3V3T=1000 ~/~/ 3V3 output power will open 1s before each sampling.

931

932

AT+5VT=1000 ~/~/ +5V output power will open 1s before each sampling.

933

934

935

* LoRaWAN Downlink Command:

936

937

07 01 aa bb Same as AT+5VT=(aa bb)

938

939

07 02 aa bb Same as AT+3V3T=(aa bb)

1.

11. Buttons

|**Button**|**Feature**

949

|**RST**|Reboot RS485-BL

1.

11. +3V3 Output

RS485-BL has a Controllable +3V3 output, user can use this output to power external sensor.

956

957

The +3V3 output will be valid for every sampling. RS485-BL will enable +3V3 output before all sampling and disable the +3V3 after all sampling.

958

959

960

The +3V3 output time can be controlled by AT Command.

**AT+3V3T=1000**

Means set +3v3 valid time to have 1000ms. So, the real +3v3 output will actually have 1000ms + sampling time for other sensors.

965

966

967

By default, the AT+3V3T=0. This is a special case, means the +3V3 output is always on at any time

1.

11. +5V Output

RS485-BL has a Controllable +5V output, user can use this output to power external sensor.

974

975

The +5V output will be valid for every sampling. RS485-BL will enable +5V output before all sampling and disable the +5v after all sampling.

976

977

978

The 5V output time can be controlled by AT Command.

**AT+5VT=1000**

Means set 5V valid time to have 1000ms. So, the real 5V output will actually have 1000ms + sampling time for other sensors.

983

984

985

By default, the AT+5VT=0. If the external sensor which require 5v and require more time to get stable state, user can use this command to increase the power ON duration for this sensor.

1.

11. LEDs

|**LEDs**|**Feature**

994

|**LED1**|Blink when device transmit a packet.

1.

11. Switch Jumper

|**Switch Jumper**|**Feature**

1001

|**SW1**|(((

1002

ISP position: Upgrade firmware via UART

1003

1004

Flash position: Configure device, check running status.

1005

)))

1006

|**SW2**|(((

1007

5V position: set to compatible with 5v I/O.

1008

1009

3.3v position: set to compatible with 3.3v I/O.,

)))

+3.3V: is always ON

+5V: Only open before every sampling. The time is by default, it is AT+5VT=0. Max open time. 5000 ms.

1. Case Study

User can check this URL for some case studies.

1020

1021

[[http:~~/~~/wiki.dragino.com/index.php?title=APP_RS485_COMMUNICATE_WITH_SENSORS>>url:http://wiki.dragino.com/index.php?title=APP_RS485_COMMUNICATE_WITH_SENSORS]]

1. Use AT Command

11. Access AT Command

1028

1029

RS485-BL supports AT Command set. User can use a USB to TTL adapter plus the 3.5mm Program Cable to connect to RS485-BL to use AT command, as below.

1030

1031

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image027.png]]

1032

1033

1034

In PC, User needs to set **serial tool**(such as [[putty>>url:https://www.chiark.greenend.org.uk/~~sgtatham/putty/latest.html]], SecureCRT) baud rate to **9600** to access to access serial console of RS485-BL. The default password is 123456. Below is the output for reference:

1035

1036

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image028.png]]

More detail AT Command manual can be found at [[AT Command Manual>>path:#AT_COMMAND]]

1.

11. Common AT Command Sequence

1046

111. Multi-channel ABP mode (Use with SX1301/LG308)

1047

1048

If device has not joined network yet:

AT+FDR

AT+NJM=0

ATZ

If device already joined network:

AT+NJM=0

ATZ

1.

11.

111. Single-channel ABP mode (Use with LG01/LG02)

1066

1067

AT+FDR Reset Parameters to Factory Default, Keys Reserve

1068

1069

AT+NJM=0 Set to ABP mode

1070

1071

AT+ADR=0 Set the Adaptive Data Rate Off

1072

1073

AT+DR=5 Set Data Rate

1074

1075

AT+TDC=60000 Set transmit interval to 60 seconds

1076

1077

AT+CHS=868400000 Set transmit frequency to 868.4Mhz

1078

1079

AT+RX2FQ=868400000 Set RX2Frequency to 868.4Mhz (according to the result from server)

1080

1081

AT+RX2DR=5 Set RX2DR to match the downlink DR from server. see below

1082

1083

AT+DADDR=26 01 1A F1 Set Device Address to 26 01 1A F1, this ID can be found in the LoRa Server portal.

ATZ Reset MCU

**Note:**

1. Make sure the device is set to ABP mode in the IoT Server.

1090

1. Make sure the LG01/02 gateway RX frequency is exactly the same as AT+CHS setting.

1091

1. Make sure SF / bandwidth setting in LG01/LG02 match the settings of AT+DR. refer [[this link>>url:http://www.dragino.com/downloads/index.php?dir=LoRa_Gateway/&file=LoRaWAN%201.0.3%20Regional%20Parameters.xlsx]] to see what DR means.

1092

1. The command AT+RX2FQ and AT+RX2DR is to let downlink work. to set the correct parameters, user can check the actually downlink parameters to be used. As below. Which shows the RX2FQ should use 868400000 and RX2DR should be 5

1093

1094

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image029.png]]

1. FAQ

11. How to upgrade the image?

1099

1100

The RS485-BL LoRaWAN Controller is shipped with a 3.5mm cable, the cable is used to upload image to RS485-BL to:

1101

1102

* Support new features

1103

* For bug fix

1104

* Change LoRaWAN bands.

1105

1106

1107

Below shows the hardware connection for how to upload an image to RS485-BL:

1108

1109

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image030.png]]

1110

1111

**Step1:** Download [[flash loader>>url:https://www.st.com/content/st_com/en/products/development-tools/software-development-tools/stm32-software-development-tools/stm32-programmers/flasher-stm32.html]].

1112

1113

**Step2**: Download the [[LT Image files>>url:http://www.dragino.com/downloads/index.php?dir=LT_LoRa_IO_Controller/LT33222-L/image/]].

1114

1115

**Step3: **Open flashloader; choose the correct COM port to update.

|(((

HOLD PRO then press the RST button, SYS will be ON, then click next

)))

|(((

Board detected

)))

|(((

)))

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image031.png]] [[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image032.png]]

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image033.png]] [[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image034.png]]

1135

1136

1137

[[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image035.png]] [[image:file:///C:/Users/93456/AppData/Local/Temp/msohtmlclip1/01/clip_image036.png]]

1.

11. How to change the LoRa Frequency Bands/Region?

1142

1143

User can follow the introduction for [[how to upgrade image>>path:#upgrade_image]]. When download the images, choose the required image file for download.

1.

11. How many RS485-Slave can RS485-BL connects?

1149

1150

1151

The RS485-BL can support max 32 RS485 devices. Each uplink command of RS485-BL can support max 16 different RS485 command. So RS485-BL can support max 16 RS485 devices pre-program in the device for uplink. For other devices no pre-program, user can use the [[downlink message (type code 0xA8) to poll their info>>path:#downlink_A8]].

1. Trouble Shooting

11. Downlink doesn’t work, how to solve it?

1158

1159

Please see this link for debug:

1160

1161

[[http:~~/~~/wiki.dragino.com/index.php?title=Main_Page#LoRaWAN_Communication_Debug>>url:http://wiki.dragino.com/index.php?title=Main_Page#LoRaWAN_Communication_Debug]]

1.

11. Why I can’t join TTN V3 in US915 /AU915 bands?

1167

1168

It might about the channels mapping. Please see for detail.

1169

1170

[[http:~~/~~/wiki.dragino.com/index.php?title=LoRaWAN_Communication_Debug#Notice_of_US915.2FCN470.2FAU915_Frequency_band>>url:http://wiki.dragino.com/index.php?title=LoRaWAN_Communication_Debug#Notice_of_US915.2FCN470.2FAU915_Frequency_band]]

1. Order Info

**Part Number: RS485-BL-XXX**

**XXX:**

* **EU433**: frequency bands EU433

1182

* **EU868**: frequency bands EU868

1183

* **KR920**: frequency bands KR920

1184

* **CN470**: frequency bands CN470

1185

* **AS923**: frequency bands AS923

1186

* **AU915**: frequency bands AU915

1187

* **US915**: frequency bands US915

1188

* **IN865**: frequency bands IN865

1189

* **RU864**: frequency bands RU864

1190

* **KZ865: **frequency bands KZ865

1. Packing Info

**Package Includes**:

1196

1197

* RS485-BL x 1

1198

* Stick Antenna for LoRa RF part x 1

* Program cable x 1

**Dimension and weight**:

1203

1204

* Device Size: 13.5 x 7 x 3 cm

1205

* Device Weight: 105g

1206

* Package Size / pcs : 14.5 x 8 x 5 cm

1207

* Weight / pcs : 170g

1. Support

* 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.

1213

* 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

1214

1215

[[support@dragino.com>>url:file:///D:/市场资料/说明书/LoRa/LT系列/support@dragino.com]]

Wiki source code of RS485-BL – Waterproof RS485 to LoRaWAN Converter

Applications

Navigation