RAK7431 MQTT Integration and Remote Configuration

The RAK7431 WisNode Bridge Serial can exchange application data with an external MQTT client through the MQTT interface of the Built-in Network Server on a compatible RAKwireless WisGate gateway.

Using this integration, you can:

• Subscribe to RAK7431 uplink data through MQTT.
• Publish LoRaWAN® downlink messages through MQTT.
• Remotely read or modify polling, DTU, and LoRaWAN settings on the RAK7431.

This guide uses MQTT.fx as an example MQTT client.

Prerequisites

Before starting:

• The RAK7431 is registered with and connected to the gateway Built-in Network Server.
• The gateway MQTT service is available.
• An MQTT client is installed. The examples in this guide use MQTTfx tool .

For the initial LoRaWAN setup, refer to the RAK7431 Quick Start Guide.

MQTT Topic Templates

Application/{{application_ID}}/device/{{device_EUI}}/join
Application/{{application_ID}}/device/{{device_EUI}}/rx
Application/{{application_ID}}/device/{{device_EUI}}/tx
Application/{{application_ID}}/device/{{device_EUI}}/ack
Application/{{application_ID}}/device/{{device_EUI}}/status

MQTT Integration

Connect an MQTT Client

1. Install and open MQTT.fx.
2. After installation, the MQTT Client must be configured. Select local mosquitto from the drop-down list and click the edit connection profiles icon marked in the image below to open the settings page.
   Figure 1: MQTT.fx connection profile
3. On the next window, input the Broker Address and Broker Port. If the Client ID is empty press Generate. Then click OK.
   • Broker Address: Address of MQTT server – the gateway IP.
   • Broker Port: Consistent with MQTT Broker Port set by the gateway - by default 1883.
     Figure 1: MQTT.fx broker settings
4. Click on the Connect button. The green dot indicates that the connection is successfully subscribed to the MQTT Broker.
   Figure 1: MQTT.fx connected to the broker

Subscribe to RAK7431 Uplink Data

1. Open the Subscribe tab.
2. Enter the required topic. To subscribe to all available topics for testing, use:

   #

3. Click Subscribe.
   Figure 1: Subscribe to MQTT topics using a wildcard

When the RAK7431 sends data, the corresponding MQTT message appears in the subscribed topic.

Figure 1: RAK7431 uplink data received through MQTT

Configure the Payload Display Format

Depending on the Built-in Network Server application settings, the uplink data field can be represented in Base64.

To change the application decode format:

1. In the gateway Web UI, go to LoRa > Applications.
2. Open the application used by the RAK7431.
3. Open the application configuration.
4. Select the required Decode Type.
5. Save the changes.

Figure 1: Configure the application payload decode type

Send Remote Configuration Commands

The RAK7431 supports remote configuration through LoRaWAN downlink commands.

When using the Built-in Network Server MQTT interface, publish the downlink message to:

Application/{{application_ID}}/device/{{device_EUI}}/tx

Remote configuration commands use FPort 129.

Example:

{
  "confirmed": true,
  "fPort": 129,
  "data": "030001000901010300000002C40B"
}

Parameter	Description
confirmed	Requests a confirmed downlink.
fPort	Remote configuration port. Use 129.
data	Remote configuration command in hexadecimal format.

Polling Task Management

Add a Scheduled Polling Task

Field	Length / Content
DTU_CMD	0x03
MSER	2 bytes
MDATA_LEN	2 bytes
TASK_ID	1 byte
DATA	Variable length

NOTE

MDATA_LEN does not include the message header.

Example:

{
  "confirmed": true,
  "fPort": 129,
  "data": "030001000901010300000002C40B"
}

A successful response uses command code 0x83.

83000100010101

Remove a Scheduled Polling Task

Example:

{
  "confirmed": true,
  "fPort": 129,
  "data": "040001000101"
}

A successful response uses command code 0x84.

84000100010101

Read a Scheduled Polling Task

Example:

{
  "confirmed": true,
  "fPort": 129,
  "data": "050001000101"
}

A successful response uses command code 0x85 and includes the task ID and task data.

8500010009010103000000002C40B

LoRaWAN Configuration

Read the LoRaWAN Configuration

Use command code 0x06.

{
  "confirmed": true,
  "fPort": 129,
  "data": "0600010000"
}

A successful response uses command code 0x86 and returns the following fields:

Field	Description
DATARATE	Data rate setting
TXPOWER	Transmit power setting
CONFIRM	Confirmed uplink setting
RETRY	Maximum retry count
ADR	Adaptive Data Rate setting
DUTY CYCLE	Duty-cycle setting

Change the LoRaWAN Configuration

Use command code 0x07.

{
  "confirmed": true,
  "fPort": 129,
  "data": "070001000601050103010"
}

The example changes the data rate to 1 and transmit power to 5.

A successful response uses command code 0x87.

8700010000

Reset the LoRaWAN Configuration

{
  "confirmed": true,
  "fPort": 129,
  "data": "1D00010000"
}

A successful response uses command code 0x9D.

9D00010000

DTU Configuration

Read the DTU Configuration

Use command code 0x08.

{
  "confirmed": true,
  "fPort": 129,
  "data": "0800010000"
}

A successful response uses command code 0x88 and includes:

Field	Description
POLL ENABLE	Scheduled polling status
POLL PERIOD	Polling period in seconds
BUS TIMEOUT	RS485 bus timeout
RETRY	Retry count after bus timeout
RS485	RS485 bus parameters

Change the DTU Poll Configuration

Use command code 0x09.

{
  "confirmed": true,
  "fPort": 129,
  "data": "09000100080100000E10010050"
}

The example changes the polling period to one hour.

A successful response uses command code 0x89.

8900010000

Reset the DTU Configuration

{
  "confirmed": true,
  "fPort": 129,
  "data": "1E00010000"
}

A successful response uses command code 0x9E.

9E00010000