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RAK4200 Module Quick Start Guide

Prerequisites​

What Do You Need?​

Before going through the step in the installation guide of the RAK4200 WisDuo LPWAN Module, make sure to prepare the necessary items listed below:

Hardware Tools​

  1. RAK4200 WisDuo LPWAN Module
  2. Windows PC
  3. USB to TTL adapter
  4. RAKDAP1 Flash and Debug Tool

Software Tools​

Definition of Terms​

List of Acronyms​
AcronymMeaning
ABPActivation By Personalization
BLEBluetooth Low Energy
DFUDevice Firmware Upgrade
EUIExtender Unique Identifier
LoRaLong Range
OTAAOver The Air Activation
TTNThe Things Network
P2PPeer-to-Peer

Product Configuration​

Connecting to the RAK4200 Console​

During the configuration of the module through the AT commands, it is possible to read the console output. You can connect to the console of the RAK4200 module through the UART interface.

Connect to the RAK4200​

In this document, a RAK4200 module is used for demonstration. Use a USB to TTL adapter to connect to the module. In case the RAK4200 is mounted on an evaluation board or a customized PCB, then use the appropriate interface to connect to the serial port.

  1. Connect the RAK4200 to a USB to TTL adapter, as shown in Figure 1. Connect the adapter to a USB port of your Windows PC.
Figure 7435: RAK4200 module connection

  1. Install a serial communication tool. Any serial communication tool will work, but it is recommended to use the RAK Serial Port Tool.

  2. Open the RAK Serial Port Tool.

Figure 7436: RAK Serial Port Tool
  1. To find the COM Port number for your device, go to Device Manager by pressing Windows + R and type devmgmt.msc, or search in the Start Menu. Look for Ports (COM & LPT) and find the name USB-SERIAL CH340. Take note of the COM Port number.
Figure 7437: Device Manager
NOTE

If you didn't find any port with the name USB-Serial CH340, make sure you have installed the CH340 drivers on your Windows PC.

  1. Fill in the serial communication parameters: COM Port Number from the Device Manager and Baudrate 115200, then click the “OPEN” button.

  2. The RAK4200 console output can now be read in the RAK Serial Port Tool, as shown in Figure 4.

Figure 7438: RAK serial port tool connected to RAK4200

Configure RAK4200​

To connect the RAK4200 module to a LoRa P2P network or a LoRaWAN network, the module must be configured and LoRa parameters must be set by sending AT commands through the UART interface.

Connect the RAK4200 module to the Windows PC as described in the previous section. Using the Serial communication tool, it is possible to send commands to the RAK4200. For example: Sending the at+version command will display the current firmware version, as shown in Figure 5. For more supported commands, refer to AT Commands for RAK4200.

Figure 7439: at+version command response

Connecting to The Things Network (TTN)​

This section shows how to connect the RAK4200 module to The Things Network (TTN) platform. As described in the TTN’s website: "The engine of The Things Network is our technology - a robust yet flexible and enterprise-ready LoRaWAN network server stack. Our stack caters to the needs of demanding LoRaWAN deployments, from covering the essentials to advanced security configurations and device life cycle management. Backed by SLAs to meet your availability requirements, facilitated by our team of support engineers"

Figure 7440: RAK4200 in the context of the TTN

As shown in Figure 6, the RAK4200 module is one of the devices located on the left side. In the context of an IoT solution, the objective is to deploy devices to sense the relevant process variables and transmit the data to the backend servers located in the cloud. The data will be processed and integrated as part of a larger solution that, ultimately, could generate efficiency, traceability, predictability capacity among others.

The RAK4200 module can be part of this ecosystem, and the objective of this section is to demonstrate how simple is to send data to TTN using LoRaWAN. Users must be aware that to achieve this, the RAK4200 must be located inside of coverage of a LoRaWAN gateway.

In summary, these are the requirements:

  • Have an account on the TTN website.
  • Have access to a LoRaWAN gateway subscribed to the TTN. The frequency band set for the RAK4200 needs to be consistent with the frequency band of the gateway.
  • The "RAK Serial Port Tool" provided by RAKWireless.
  • The RAK4200 module is connected to a USB to TTL adapter, as shown in Figure 1.
NOTE

The frequency band used in this example is EU868, which is supported by the high-frequency version of the RAK4200 module.

The steps for sending data to the TTN platform from a RAK4200 module can be summarized as:

  • Sign up and log in to the TTN console
  • Create a new Application
  • Register a new device in the platform
  • Configure the Join Mode
    • OTAA mode on the platform
    • OTAA mode on the RAK4200 module
    • ABP mode on the platform
    • ABP mode on the RAK4200 module
    • Send data from the module and receive it at the platform

In the following sections, each of these steps will be explained in detail. You can choose either to use ABP or OTAA mode to register the device on the network server.

Registering the RAK4200 to TTN​

To register the RAK4200 to TTN, execute the following steps:

Login to The Things Network Platform​
  1. Access and login into the TTN, and go to its “Console” section by clicking on the Console icon. You should see an interface similar to Figure 7.
Figure 7441: Console Page
Create a New Application​
  1. Choose the “APPLICATIONS” option.
Figure 7442: Application section
  1. Click on the “add application” link.
Figure 7443: New Application Form

  1. Fill in the correct contents in the “Add application form”:

    • Application ID: a unique ID on the TTN network that should be in lower case with no spaces
    • Description: This is a short and concise human-readable description of your application
    • Application EUI: automatically generated by TTN
    • Handler Registration: select the handler you want to register this application to
Figure 7444: Fill the Add Application Form
  1. To finish, click on the “Add application” button and a page similar to Figure 11 will appear.
Figure 7445: Application Overview
Register a New Device in the Platform​
  1. In the “Application details” page, find the “DEVICES” section by the middle of this page.
Figure 7446: DEVICES section
  1. Click on the “register device” link, then a “register device form” will appear.
Figure 7447: Register a New Device

In this form, the device ID must be unique for the application and must be completed with lower case, alphanumeric characters. The rest of the parameters in the form are very important for the LoRaWAN protocol:

  • Device EUI
  • Application Key
  • Application EUI

The TTN platform can generate these parameters randomly by leaving those fields empty or you can enter already existing values.

  1. Press the “Register” button to finish the process. The registration results will appear summarized, as shown in Figure 14.
Figure 7448: New Device Overview

LoRaWAN Join Mode​

The LoRaWAN specification defines that to join in a LoRaWAN network, each end-device has to be personalized and activated. Activation can be done either via Over-The-Air-Activation (OTAA) or via Activation-By-Personalization (ABP). In OTAA, the end-device previously personalized is activated when deployed or reset. In ABP, personalization and activation are done as a single step.

Join in OTAA Mode​
Configure the OTAA Mode on the TTN Platform​

As shown in Figure 15, the default activation mode in TTN is the OTAA mode. Therefore, no further actions are required on the platform side.

Figure 7449: New Device Parameters

Three parameters from TTN setup are used to configure the RAK4200: “Device EUI”, “Application EUI”, and “App Key”.

Configure the OTAA Mode on the RAK4200 Module​

RAK4200 complies with LoRaWAN 1.0.2 specification. By default, the LoRa join mode is OTAA, and the LoRa class is Class A.

To set up the RAK4200 module to join the TTN using OTAA, start by connecting the RAK4200 module to the computer. Open the RAK Serial Port Tool and wait for the communication to start. It is recommended to test the serial communication by sending an AT command as at+get_config=lora:status or at+version.

Figure 7450: RAK Serial Port Tool connected to a RAK4200

As an example, the following parameters will be configured in RAK4200:

  • LoRa join mode: OTAA
  • LoRa class: Class A
  • LoRa region: EU868
  • Device EUI: 5e9d1e0857cf25f1 (from TTN registration)
  • Application EUI: 5e9d1e0857cf25f1 (from TTN registration)
  • Application Key: f921d50cd7d02ee3c5e6142154f274b2 (from TTN registration)
  1. Set the LoRa join mode to OTAA.
at+set_config=lora:join_mode:0
  1. Set the LoRa class to Class A.
at+set_config=lora:class:0
  1. Set the frequency/region.

For the Europe region, type the command:

at+set_config=lora:region:EU868

NOTE

Remember that the device frequency shall be in the same band of the gateway.

  1. Set the Device EUI.

Get the Device EUI number from TTN registration.

at+set_config=lora:dev_eui:5e9d1e0857cf25f1
  1. Set the Application EUI.

Get the Application EUI number from the TTN registration.

NOTE

All zero value Application EUI at+set_config=lora:app_eui:0000000000000000 is not supported and will return error.

at+set_config=lora:app_eui:5e9d1e0857cf25f1
  1. Set the Application Key.

Get the Application Key from the TTN registration.

at+set_config=lora:app_key:f921d50cd7d02ee3c5e6142154f274b2
  1. Save the RAK4200 parameters.

Reset the RAK4200 to save the parameters.

Figure 17 summarizes the set of commands sent over the console to set the OTAA mode on the RAK4200.

Figure 7451: RAK4200 LoRa parameters configuration over the RAK Serial Port Tool
  1. Finally, send the command to join in OTAA mode.
at+join
  • If the request was successfully received by a LoRa gateway, then the “OK Join Success” message will be shown in the console after a few seconds. See Figure 18.
Figure 7452: RAK4200 join OTAA mode
  1. Send data from RAK4200 to TTN.

To send the string 1234567890 over LoRa port 2, type the command:

at+send=lora:2:1234567890
Figure 7453: RAK4200 example of sending data to the TTN, in this case, the string 123456890 over port 2
  1. The data will appear on the TTN console: Applications -> rak_node_test -> Devices -> rak_node -> Data
Figure 7454: TTN console showing the data received from RAK4200
Join in ABP Mode​
Configure the ABP Mode on the Platform​

As shown previously, the default activation mode in TTN is the OTAA mode. Therefore, no further actions are required on the platform side.

Three parameters from TTN setup are used to configure the RAK4200: “Device EUI”, “Application EUI”, and “App Key”.

For joining TTN in ABP mode, first, you need to change the activation method to ABP. It is done on the TTN console under the “Device Settings” page, as shown in Figure 21.

Figure 7455: Change the activation mode to ABP

As for the OTAA mode, three TTN parameters will be used to configure the RAK4200 for ABP mode: “Device Address”, “Network Session Key”, and “App Session Key”. These fields can be left empty in the form and TTN will complete them with random values. In other case, you can complete them with specific values.

Figure 7456: ABP Mode Parameters

After completing the mode change, the device parameters will be summarized on: Applications -> rak_node_test -> Devices -> rak_node. See Figure 23.

Figure 7457: ABP mode configuration finalized
Configure the ABP Mode on the RAK4200 Module​

RAK4200 complies with LoRaWAN 1.0.2 specification. By default, the LoRa join mode is OTAA, and the LoRa class is Class A.

To set up the RAK4200 module to join the TTN using ABP, start by connecting the RAK4200 module to the Windows PC. Then open the RAK Serial Port Tool and wait for the communication to start. It is recommended to test the serial communication by sending an AT command as at+get_config=lora:status or at+version.

Figure 7458: RAK Serial Port Tool connected to a RAK4200

As an example, the following parameters will be configured in RAK4200:

  • LoRa join mode: ABP
  • LoRa class: Class A
  • LoRa region: EU868
  • Device address: 26031171 (from TTN registration)
  • Network Session Key: c280cb8d1df688bc18601a97025c5488 (from TTN registration)
  • Application Session Key: 4d42ec5caf97f03d833cdaf5003f69e1(from TTN registration)
  1. Set LoRa join mode to ABP.
at+set_config=lora:join_mode:1
  1. Set the LoRa class to Class A.
at+set_config=lora:class:0
  1. Set the Frequency/Region.

For the Europe region, type the command:

at+set_config=lora:region:EU868
NOTE

Remember that the device frequency shall be in the same band of the gateway.

  1. Set the Device Address.

Get the Device Address from TTN registration.

at+set_config=lora:dev_addr:26031171
  1. Set the Network Session Key.

Get the Network Session Key from the TTN registration.

at+set_config=lora:nwks_key:c280cb8d1df688bc18601a97025c5488
  1. Set the Application Key.

Get the Application Key from the TTN registration.

at+set_config=lora:apps_key: 4d42ec5caf97f03d833cdaf5003f69e1
  1. Save the RAK4200 parameters.

Reset the RAK4200 to save the parameters. Figure 25 summarizes the set of commands sent over the console for setting the OTAA mode on the RAK4200.

Figure 7459: RAK4200 LoRa parameters configuration over the Serial Port Tool
  1. Send the command to join in ABP mode.
at+join
NOTE

The ABP mode in LoRaWAN does not require to join a network before sending a LoRaWAN package. But to keep the consistency of the internal states of the firmware of the RAK4200 module, it is still required to send the at+join command in the ABP mode.

Right after sending the command, the “OK Join Success” should be replied to in the console the same, as shown in Figure 25.

Figure 7460: RAK Serial port tool join LoRaWAN in ABP mode
  1. Send data from RAK4200 to ChirpStack.

To send the string 1234567890 over LoRa port 2, type the command:

at+send=lora:2:1234567890
Figure 7461: RAK Serial Port Tool, sending a message in ABP mode
  • The data will appear on the TTN console: Applications -> rak_node_test -> Devices -> rak_node -> Data.
Figure 7462: TTN console with received data from RAK4200

Connecting with ChirpStack​

This section shows how to connect the RAK4200 module to the ChirpStack platform. As described on ChirpStack’s website:

“The ChirpStack open-source LoRaWAN Network Server stack provides open-source components for LoRaWAN networks. Together they form a ready-to-use solution including a user-friendly web interface for device management and APIs for integration.

The modular architecture makes it possible to integrate within existing infrastructures. All components are licensed under the MIT license and can be used for commercial purposes.”

Figure 7463: RAK4200 module in the context of the ChirpStack platform

The architecture of the ChirpStack platform is shown in Figure 28. Similar to the case of TTN, the RAK4200 module is located in the periphery and will transmit the data to the backend servers through a LoRa gateway. For more information about this architecture, refer to Chirpstack website.

In this section, it is assumed that you are using a RAK LoRa gateway, such as RAK7243. The gateway must be configured to ChirpStack deployment. More information about that can be found at Connect the Gateway with Chirpstack.

You can also check the other RAK gateways RAK WisGate products.

NOTE

The frequency band used in this example is EU868, which is supported by the high-frequency version of RAK4200.

And these are the steps to send data to the ChirpStack platform from a RAK4200 module:

  • Create a new Application
  • Register a new device on the platform
  • Configure the Join Mode:
    • OTAA mode on the platform
    • OTAA mode on the RAK4200 module
    • ABP mode on the platform
    • ABP mode on the RAK4200 module
    • Send data from the module and receive it at the platform

The following section gives the details of each of these aforementioned steps. As usual, you can either choose to use ABP or OTAA mode to register the device to the network server.

Create a New Application​

  1. Go to the “Applications” section, as shown in Figure 30.
Figure 7464: Applications section of the RAK’s ChirpStack LoRaServer
  1. By default, a new Application should be created, although it is possible to reuse the existing ones. For this setup, create a new Application by clicking on the “+ CREATE” button and filling in the required parameters, as shown in Figure 31 and Figure 32.
Figure 7465: Creating a new Application

  1. For this setup, create an Application named “rak_node_test”. Fill in the required parameters, as shown in Figure 32.

  2. To finish, click on the “CREATE APPLICATION” button.

ChirpStack LoRaServer supports multiple system configurations, with only one by default.

  • Application Name: rak_node_test
  • Application Description: test
  • Service-profile: Select the system profile. Choose service-profile-built-in

The Application Description field is just a descriptive text.

Figure 7466: Filling the Application Parameters

Register a New Device in the Platform​

  1. Choose the Application created in the previous step, then select the “DEVICES” tab, as shown in Figure 33 and Figure 34.
Figure 7467: List of applications created
Figure 7468: Device tab of an Application
  1. Once inside of the “DEVICES” tab, create a new device (LoRa node) by clicking on the “+ CREATE” button.
Figure 7469: Add a new device at the Devices tab
Figure 7470: New device registration form
  1. Fill in the parameters requested as appears in Figure 37:
  • Device name and Device description: These are just descriptive texts.
  • Device EUI: This interface allows you to generate a Device EUI automatically by clicking the icon highlighted in red in Figure 37. You can also add a specific Device EUI directly in the form.
  • Device Profile: To join in OTAA mode, select “device_profile_otaa”. To join in ABP mode, select “device_profile_abp”.
  1. To finish, click on the “CREATE DEVICE” button.
NOTE

ChirpStack does not support AS923 in ABP mode.

Figure 7471: Generate a new Device EUI in the device registration form

LoRaWAN Join Mode​

The LoRaWAN specification defines that to join in a LoRaWAN network, each end-device has to be personalized and activated. Activation can be done either via Over-The-Air-Activation (OTAA) or via Activation-By-Personalization (ABP). In OTAA, the end-device previously personalized is activated when deployed or reset. In ABP, personalization and activation are done as a single step.

Join in OTAA Mode​
Configure the OTAA Mode on the Platform​
  1. If you have selected “device_profile_otaa”, as shown in Figure 38, then after the device is created, an Application Key must be also created for this device.
Figure 7472: Choosing OTAA mode in the device registration form
  1. A previously created Application Key can be entered here, or a new one can be generated automatically by clicking the icon highlighted in red, as shown in Figure 39.
Figure 7473: Application Key for the OTAA mode in the device registration form

  1. Once the Application Key is added to the form, the process can be finalized by clicking on the “SET DEVICE-KEYS” button.

  2. As shown in Figure 40, a new device should be listed in the “DEVICES” tab. The most important parameters, such as the Device EUI, are shown in the summary.

Figure 7474: New created device listed in the DEVICES tab
  1. To end the process, it is a good practice to review that the Application Key is properly associated with this device. The Application Key can be verified in the “KEYS(OTAA)” tab, as shown in Figure 41.
Figure 7475: Application Key associated with the new device.
NOTE

Standard OTAA mode requires the Device EUI, Application Key, and Application EUI; but in the ChirpStack implementation, only Device EUI and the Application Key are mandatory. The Application EUI is not required nor recorded in the Application tab. Nevertheless, the Application EUI is a mandatory parameter in the RAK4200 module firmware. To resolve this mismatch, reuse the Device EUI as the Application EUI during the configuration on the side of the node.

Configure the OTAA Mode on the RAK4200 Module​

RAK4200 complies with LoRaWAN 1.0.2 specification. By default, the LoRa join mode is OTAA, and the LoRa Class is Class A. To set up the RAK4200 module to join ChirpStack using OTAA, start by connecting the RAK4200 module to the computer (see Figure 1). Open the RAK Serial Port Tool, and wait for the communication to start. It is recommended to test the serial communication by sending an AT command as at+get_config=lora:status or at+version.

Figure 7476: RAK Serial Port Tool connected to a RAK4200

As an example, the following parameters will be configured in RAK4200:

  • LoRa join mode: OTAA
  • LoRa class: Class A
  • LoRa region: EU868
  • Device EUI: 5e9d1e0857cf25f1 (from ChirpStack registration)
  • Application EUI: 5e9d1e0857cf25f1 (from ChirpStack registration)
  • Application Key: f921d50cd7d02ee3c5e6142154f274b2 (from ChirpStack registration)
  1. Set the LoRa join mode to OTAA.
at+set_config=lora:join_mode:0
  1. Set the LoRa Class to Class A.
at+set_config=lora:class:0
  1. Set the frequency/region.

For the Europe region, type the command:

at+set_config=lora:region:EU868
  1. Set the Device EUI.

Get the Device EUI number from ChirpStack registration.

at+set_config=lora:dev_eui:5e9d1e0857cf25f1
  1. Set the Application EUI.

Get the Application EUI number from the ChirpStack registration.

at+set_config=lora:app_eui:5e9d1e0857cf25f1
NOTE

The Application EUI parameter is not required in the ChirpStack platform; therefore, it is possible to use the same id as the Device EUI. Otherwise, the firmware will complain.

  1. Set the Application Key.

Get the Application Key from the TTN registration.

Type command:

at+set_config=lora:app_key:f921d50cd7d02ee3c5e6142154f274b2
  1. Save the RAK4200 parameters.

Reset the RAK4200 to save the parameters.

Figure 42 summarizes the set of commands sent over the console for setting the OTAA mode on the RAK4200.

Figure 7477: RAK4200 LoRa parameters configuration over the Serial Port Tool
  1. Send command to join in OTAA mode.
at+join
  • If the request is successfully received by a LoRa gateway, then the “OK Join Success” message will be shown in the serial console after a few seconds.
Figure 7478: RAK Serial Port Tool, join the network

The JoinRequest and JoinAccept messages are also displayed on the ChirpStack console, specifically in the “LORAWAN FRAMES” tab, as shown in Figure 45.

Figure 7479: ChirpStack Console, checking LoRaWAN join request
  1. Send data from RAK4200 to ChirpStack.

To send the string 1234567890 over LoRa port 2, type the command:

at+send=lora:2:1234567890
Figure 7480: RAK Serial Port Tool, send a LoRaWAN message.

On the ChirpStack platform, the messages shall appear in the LORAWAN FRAMES tab, as shown in Figure 47. By convention, messages sent from nodes to gateways are considered as “UPLINK”, while messages sent by gateways to nodes are considered as “DOWNLINK”.

Figure 7481: ChirpStack Console, checking LoRaWAN messages received.
Join in ABP Mode​
Configure the ABP Mode on the Platform​

During the registration of a new device, if “device_profile_abp” is selected, as shown in Figure 48, then the ChirpStack platform will assume that this device will join the LoRaWAN network using the ABP mode.

NOTE

Check Disable frame-counter validation. If the server cannot synchronize the node-side counting, the transmission will fail.

Figure 7482: ChirpStack Console, configuring a device in ABP mode

After selecting the ABP mode, the following parameters appear in the Activation tab (See Figure 49):

  • Device address
  • Network Session Key
  • Application Session Key
Figure 7483: ChirpStack Console, parameters required for the ABP mode

The parameters can be generated as random numbers by the platform or you can set the values. Once these parameters are filled properly, the process is completed by clicking on the “(RE)ACTIVATE DEVICE” button.

Configure the ABP Mode on the RAK4200 Module​

RAK4200 complies with LoRaWAN 1.0.2, by default the LoRa join mode is OTAA and the LoRa Class is Class A. To set up the RAK4200 module to join ChirpStack using ABP, start by connecting the RAK4200 module to the computer (see Figure 1). Open the RAK Serial Port Tool, and wait for the communication to start. It is recommended to test the serial communication by sending an AT command as at+get_config=lora:status or at+version.

Figure 7484: RAK Serial Port Tool connected to a RAK4200

As an example, the following parameters will be configured in RAK4200:

  • LoRa join mode: ABP
  • LoRa class: Class A
  • LoRa region: EU868
  • Device address: 26011af9 (from ChirpStack registration)
  • Network Session Key: c280cb8d1df688bc18601a97025c5488 (from ChirpStack registration)
  • Application Session Key: 4d42ec5caf97f03d833cdaf5003f69e1 (from ChirpStack registration)
  1. Set the LoRa join mode to ABP.
at+set_config=lora:join_mode:1
  1. Set the LoRa Class to Class A.
at+set_config=lora:class:0
  1. Set the frequency/region.

For the Europe region, type the command:

at+set_config=lora:region:EU868
  1. Set the Device Address.

Get the Device Address from ChirpStack registration.

at+set_config=lora:dev_addr:26011af9
  1. Set the Network Session Key.

Get the Network Session Key from the ChirpStack registration.

at+set_config=lora:nwks_key:c280cb8d1df688bc18601a97025c5488
  1. Set the Application Key.

Get the Network Session Key from the ChirpStack registration.

at+set_config=lora:apps_key:4d42ec5caf97f03d833cdaf5003f69e1
  1. Save RAK4200 parameters.

Reset the RAK4200 to save the parameters.

Figure 51 summarizes the set of commands sent over the console to set the ABP mode on RAK4200.

Figure 7485: RAK4200 LoRa parameters configuration over the Serial Port Tool
  1. Send command to join in ABP mode.

All the parameters required to join to a LoRaWAN network in OTAA mode have been configured. After the reset, you can send the join command:

at+join

Right after sending the command, the “OK Join Success” should be replied to in the console, as shown in Figure 52.

Figure 7486: RAK4200 Serial Port Tool join
NOTE

The ABP mode in LoRaWAN does not require to join a network before sending a LoRaWAN package to the air. Moreover, to keep the consistency of the internal states of the firmware of the RAK4200 module, it is still required to send the at+join command in the ABP mode.

  1. Send data from RAK4200 to ChirpStack.

To send the string 1234567890 over LoRa port 2, type the command:

at+send=lora:2:1234567890
Figure 7487: Sending a message in ABP mode
  • The console will feedback with an “OK” message (see Figure 53). The sent data shall be displayed in the ChirpStack console.

LoRa P2P Mode​

This section will show how to set and link two RAK4200 units to work in LoRa P2P mode. The two RAK4200 units shall be set to operate at the same frequency, e.g: EU868.

As shown in the previous sections, the setup of the RAK4200 units is done by connecting them with a general-purpose computer through the UART port. The setup of each RAK4200 can be done separately, but testing the LoRa P2P mode will require having both units connected simultaneously to a UART port (this could be one computer with 2 ports or 2 computers with one UART port each).

  1. To set the RAK4200 to work in LoRa P2P mode, open the RAK Serial port tool and send the command, as shown in Figure 54: at+set_config=lora:work_mode:1.
Figure 7488: RAK4200 setting to LoRa P2P mode
  1. Configure the LoRa P2P parameters for both units. The command for setting the parameters has the format. at+set_config=lorap2p:XXX:Y:Z:A:B:C

The parameters are as follows:

  • XXX: Frequency in Hz.
  • Y: Spreading factor, [6, 7, 8, 9, 10, 11, 12].
  • Z: Bandwidth, [0:125 kHz, 1:250 kHz, 2:500 kHz]
  • A: Coding Rate, [1:4/5, 2:4/6, 3:4/7, 4:4/8]
  • B: Preamble Length, 5~65535.
  • C: Power in dBm, 5~20.

For this example, the LoRa parameters are:

  • Link frequency: 869525000 Hz
  • Spreading factor: 7
  • Bandwidth: 125 kHz
  • Coding Rate: 4/5
  • Preamble Length: 5
  • Power: 5 dBm
  1. It is translated into the following RAK4200 AT command that is sent to both units, as shown in Figure 55:

at+set_config=lorap2p:869525000:7:0:1:5:5

Figure 7489: Setting both RAK4200 units with the LoRa P2P parameters
  1. Next, set the transmission mode of the module. In this example, Unit 1 is set to sender mode, and unit 2 is set to receiver mode by AT command. See Figure 56.

Unit 1(Sender): at+set_config=lorap2p:transfer_mode:2 Unit 2(Receiver): at+set_config=lorap2p:transfer_mode:1

Figure 7490: Set the module in the sender (left) and in the receiver (right) mode
  1. To send a message with the string “123456890” from Unit 1 to Unit 2, use the command on Unit 1:

at+send=lorap2p:1234567890

The message will be automatically received by Unit 2. See Figure 57.

Figure 7491: Sending a message from RAK unit 1(left) to RAK unit 2 (right)

Miscellaneous​

Firmware Update​

Before to start working with the RAK4200, it is recommended to keep the RAK4200 module updated to the latest version of the firmware.

NOTE

For RAK4200 modules with firmware version V3.0.0.12 and below, you need to use the STM32CubeProgrammer to upgrade your firmware and upload the .hex file (not the .bin file) of the latest RAK4200 firmware. The lower versions of the firmware have a different bootloader code and will not work on the RAK DFU Tool.

In the following sections, two (2) options for flashing new firmware in a RAK4200 module are shown: “Firmware Upgrade through DAPLink” and “Firmware Upgrade through UART1”.

Firmware Upgrade Through DAPLink​

Refer to the RAKDAP1 Flash and Debug Tool Quickstart Guide.

Firmware Upgrade Through UART1​

Minimum Hardware and Software Requirements​
ComputerA Windows/Linux/Mac computer
Firmware FileBin firmware downloaded from the website.
OthersA USB to TTL adapter.
Firmware Upgrade Procedure​

Follow this procedure to upgrade the firmware in Device Firmware Upgrade (DFU) mode through the UART1 interface.

  1. Download the latest application firmware of the RAK4200 module.

  2. Download the RAK Device Firmware Upgrade (DFU) tool. In this folder are the different DFU tools depending on your machine's OS.

  3. Connect the RAK4200 module with a computer through USB to TTL adapter as shown in Figure 58:

  4. Open the RAK Device Firmware Upgrade (DFU) tool. Select the serial port and baud rate of the module, and then click on the "Select Port" button.

Figure 7492: Device Firmware Upgrade Tool
  1. Click on the "Select Firmware" button and choose the application firmware file of the module with the suffix ".bin".
Figure 7493: Select firmware
  1. Click on the "Upgrade" button to upgrade the device. After the upgrade is complete, the RAK4200 module is now ready to work with the new firmware.
Figure 7494: Firmware upgrading
Figure 7495: Upgrade successful