RAK 7431 - Custom Payload

For our use case we need to modify the LPWAN payload since we query Modbus devices at a high sampling interval and need to pack the data in a compact payload. As I understood from this post: Custom firmware, this is unfortunately not possible, since the code is not open source.

Is it possible to customize the hardware in the RAK7431 so that the lora Payload can be modified?

  • If yes, which components need to be replaced and what replacements are required?

  • How do we need to customize the code of the open source modules for this to work?

  • Are the hardware interfaces of the case still compatible with open source components?

Thank you for your help!

@beegee could you give support?



I do not have the RAK7431 (not my product) but as far as I know it is build with one of our WisDuo EVB’s which are basically WisBlock Base Boards and have compatible Sensor and IO slots.

It could work to replace it with WisBlock modules like the
RAK19007 Base Board
RAK4631 Core module or any other Core module with LoRaWAN
RAK5802 RS485

But for the firmware side, I have never used Modbus or RS485, so I can only refer to our example codes in the WisBlock Repo.

Thanks @beegee for the suggestions.
Could you tell me whose product it is / whom to contact for details?

Can you help with more details about the RAK7431

Hello @rs485toLWAN,

RAK7431 is an end device that is not Open-Source, so you can not modify its firmware.
You request custom functionality so you will have to create your own firmware to work with it.
You can use the modules that Bernd shared above to make device hardware similar to RAK7431 and RUI3.0 to create custom firmware.

Best Regards,