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.

26

)))

27

28

(((

29

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.

50

)))

51

52

[[image:1652953304999-717.png||height="424" width="733"]]

53

54

== 1.2 Specifications ==

**Hardware System:**

* STM32L072CZT6 MCU

* SX1276/78 Wireless Chip

60

* Power Consumption (exclude RS485 device):

** Idle: 6uA@3.3v

*

** 20dB Transmit: 130mA@3.3v

65

66

**Interface for Model:**

67

68

* 1 x RS485 Interface

69

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

70

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

71

* 1 x one wire interface

72

* 1 x Interrupt Interface

73

* 1 x Controllable 5V output, max

**LoRa Spec:**

* Frequency Range:

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

79

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

80

* 168 dB maximum link budget.

81

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

82

* Programmable bit rate up to 300 kbps.

83

* High sensitivity: down to -148 dBm.

84

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

85

* Excellent blocking immunity.

86

* Fully integrated synthesizer with a resolution of 61 Hz.

87

* LoRa modulation.

88

* Built-in bit synchronizer for clock recovery.

89

* Preamble detection.

90

* 127 dB Dynamic Range RSSI.

91

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

== 1.3 Features ==

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

96

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

97

* AT Commands to change parameters

98

* Remote configure parameters via LoRaWAN Downlink

99

* Firmware upgradable via program port

100

* Support multiply RS485 devices by flexible rules

101

* Support Modbus protocol

102

* Support Interrupt uplink

103

104

== 1.4 Applications ==

105

106

* Smart Buildings & Home Automation

107

* Logistics and Supply Chain Management

* Smart Metering

* Smart Agriculture

* Smart Cities

* Smart Factory

== 1.5 Firmware Change log ==

114

115

[[RS485-BL Image files – Download link and Change log>>url:http://www.dragino.com/downloads/index.php?dir=LoRa_End_Node/RS485-BL/Firmware/||style="background-color: rgb(255, 255, 255);"]]

116

117

== 1.6 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

)))

= 2. Pin mapping and Power ON Device =

146

147

(((

148

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.

149

)))

150

151

[[image:1652953055962-143.png||height="387" width="728"]]

152

153

154

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

155

156

= 3. Operation Mode =

157

158

== 3.1 How it works? ==

159

160

(((

161

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.

162

)))

163

164

== 3.2 Example to join LoRaWAN network ==

165

166

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.

167

168

[[image:1652953414711-647.png||height="337" width="723"]]

169

170

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

171

172

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:

173

174

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

175

176

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

177

178

[[image:1652953462722-299.png]]

179

180

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

181

182

Add APP EUI in the application.

[[image:image-20220519174512-1.png]]

188

189

[[image:image-20220519174512-2.png||height="328" width="731"]]

190

191

[[image:image-20220519174512-3.png||height="556" width="724"]]

192

193

[[image:image-20220519174512-4.png]]

194

195

You can also choose to create the device manually.

196

197

[[image:1652953542269-423.png||height="710" width="723"]]

198

199

Add APP KEY and DEV EUI

200

201

[[image:1652953553383-907.png||height="514" width="724"]]

(((

**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.

206

)))

207

208

[[image:1652953568895-172.png||height="232" width="724"]]

1.

11. Configure Commands to read data

215

216

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

222

223

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

224

225

1. RS485-MODBUS mode:

226

227

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.

233

234

235

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.

236

237

238

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

239

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

240

AT+BAUDR=9600

241

242

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

243

)))

244

|AT+PARITY|(((

245

Set UART parity (for RS485 connection)

246

247

Default Value is: no parity.

)))|(((

AT+PARITY=0

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

252

)))

253

|AT+STOPBIT|(((

254

Set serial stopbit (for RS485 connection)

255

256

Default Value is: 1bit.

257

)))|(((

258

AT+STOPBIT=0 for 1bit

259

260

AT+STOPBIT=1 for 1.5 bit

261

262

AT+STOPBIT=2 for 2 bits

)))

1.

11.

111. Configure sensors

271

272

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

273

274

275

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.

276

277

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

278

|AT+CFGDEV|(((

279

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

280

281

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

282

283

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

284

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

285

286

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

1.

11.

111. Configure read commands for each sampling

295

296

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.

297

298

299

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.

300

301

302

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

303

304

305

This section describes how to achieve above goals.

306

307

308

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

309

310

311

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

312

313

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

314

315

316

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

317

318

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.

329

330

331

**Define wait timeout:**

332

333

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

334

335

336

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.

342

343

344

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

345

346

|(((

347

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

348

349

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

350

351

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

352

)))

353

354

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.

355

356

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

357

358

359

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

360

361

|(((

362

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

363

364

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

365

* **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

373

374

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

375

376

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

377

378

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

379

380

381

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

382

383

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

384

385

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

386

387

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

388

389

390

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

391

392

|(((

393

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

394

395

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

396

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

397

* **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]]

409

410

* Grab different sections.

411

412

[[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

422

423

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

428

429

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

430

431

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

432

433

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

1.

11.

111. Compose the uplink payload

441

442

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.**

443

444

445

**Examples: AT+DATAUP=0**

446

447

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

452

453

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

454

455

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

**Examples: AT+DATAUP=1**

460

461

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

Final Payload is

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

466

467

1. Battery Info (2 bytes): Battery voltage

468

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

469

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

470

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

471

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

472

473

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

474

475

476

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

477

478

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

479

480

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

481

482

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

Below are the uplink payloads:

487

488

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

489

490

491

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

492

493

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

494

495

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

496

497

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

498

499

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

1.

11.

111. Uplink on demand

506

507

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.

508

509

Downlink control command:

510

511

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

512

513

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

1.

11.

111. Uplink on Interrupt

520

521

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

522

523

AT+INTMOD=0 Disable Interrupt

524

525

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

526

527

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

528

529

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.

547

548

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

549

550

551

function Decoder(bytes, port) {

552

553

~/~/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",

564

565

~/~/payload of version

Pay_ver:bytes[2],

};

}

TTN V3 uplink screen shot.

580

581

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

582

583

1.

584

11. Configure RS485-BL via AT or Downlink

585

586

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

587

588

There are two kinds of Commands:

589

590

* **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

591

592

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

1.

11.

111. Common Commands:

597

598

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:

604

605

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

606

607

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.

612

613

**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) ====

623

624

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

629

630

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

641

* NN: The length of RS485 command

642

* XX XX XX XX: RS485 command total NN bytes

643

* 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.

648

649

* 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.

650

651

* 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.

652

653

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

654

655

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

656

657

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

658

659

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:

665

666

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

==== Set Payload version ====

672

673

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

683

684

0xAE 0F à Set PAYVER field = 0x0F

685

686

687

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

688

689

AT+COMMANDx, AT+DATACUTx and AT+SEARCHx

690

691

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.

697

698

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

699

700

AT+SEARCHx: Configure search command

* Downlink Payload:

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

706

707

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

708

709

Format: AF MM NN LL XX XX XX XX YY

Where:

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

714

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

715

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

716

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

717

* 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

722

723

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

724

725

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

726

727

728

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

729

730

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

731

732

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

733

* 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

734

735

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

736

737

738

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

739

740

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]].

741

742

This command is valid since v1.3 firmware version

743

744

745

AT+MBFUN has only two value:

746

747

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

748

749

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.

750

751

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

Example:

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

756

* 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.

757

* 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.

758

759

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

760

761

762

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

* Downlink Commands:

A9 aa -à Same as AT+MBFUN=aa

768

769

770

==== RS485 command timeout ====

771

772

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.

773

774

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**

795

796

797

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

798

799

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

800

801

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

813

814

0xAD 01 à Same as AT+DATAUP=1

815

816

817

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

818

819

Ask device to send an uplink immediately.

* Downlink Payload:

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

824

825

826

==== Clear RS485 Command ====

827

828

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

834

835

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

836

837

Example screen shot after clear all RS485 commands.

The uplink screen shot is:

842

843

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

* Downlink Payload:

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

849

850

851

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

852

853

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

879

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

880

881

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

882

883

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

884

885

886

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

887

888

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.

895

896

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

897

898

899

* LoRaWAN Downlink Command:

900

901

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

902

903

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

1.

11. Buttons

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

912

|**RST**|Reboot RS485-BL

1.

11. +3V3 Output

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

918

919

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.

920

921

922

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.

927

928

929

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.

936

937

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.

938

939

940

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.

945

946

947

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**

956

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

1.

11. Switch Jumper

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

962

|**SW1**|(((

963

ISP position: Upgrade firmware via UART

964

965

Flash position: Configure device, check running status.

966

)))

967

|**SW2**|(((

968

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

969

970

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.

980

981

[[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

988

989

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.

990

991

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

992

993

994

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:

995

996

[[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

1006

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

1007

1008

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)

1026

1027

AT+FDR Reset Parameters to Factory Default, Keys Reserve

1028

1029

AT+NJM=0 Set to ABP mode

1030

1031

AT+ADR=0 Set the Adaptive Data Rate Off

1032

1033

AT+DR=5 Set Data Rate

1034

1035

AT+TDC=60000 Set transmit interval to 60 seconds

1036

1037

AT+CHS=868400000 Set transmit frequency to 868.4Mhz

1038

1039

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

1040

1041

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

1042

1043

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.

1050

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

1051

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.

1052

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

1053

1054

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

1. FAQ

11. How to upgrade the image?

1059

1060

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

1061

1062

* Support new features

1063

* For bug fix

1064

* Change LoRaWAN bands.

1065

1066

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

1067

1068

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

1069

1070

**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]].

1071

1072

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

1073

1074

**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]]

1094

1095

1096

[[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?

1101

1102

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?

1108

1109

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?

1116

1117

Please see this link for debug:

1118

1119

[[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?

1125

1126

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

1127

1128

[[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

1139

* **EU868**: frequency bands EU868

1140

* **KR920**: frequency bands KR920

1141

* **CN470**: frequency bands CN470

1142

* **AS923**: frequency bands AS923

1143

* **AU915**: frequency bands AU915

1144

* **US915**: frequency bands US915

1145

* **IN865**: frequency bands IN865

1146

* **RU864**: frequency bands RU864

1147

* **KZ865: **frequency bands KZ865

1. Packing Info

**Package Includes**:

1152

1153

* RS485-BL x 1

1154

* Stick Antenna for LoRa RF part x 1

1155

* Program cable x 1

1156

1157

**Dimension and weight**:

1158

1159

* Device Size: 13.5 x 7 x 3 cm

1160

* Device Weight: 105g

1161

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

1162

* 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.

1167

* 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

1168

1169

[[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