RAK3172 + RUI Version 4.0.1


We wish to understand is there any compiler optimization for code size as after updating to 4.0.1 version our ROM overflowed by 8400 bytes.
Is there any way to optimize it through compiler?
Can we get a more flash version RAK3172?

Please guide.


At the moment the answer to both is No.

Reducing the code size of RUI3 is on the todo list, but not easy to achieve, as it is based on pre-compiled code.

We have no plans to change the STM32WLE5 to a version with larger Flash.


Can you please let us know further what is “Support AT” option in Tools menu?
What should be it’s setting: ON or OFF?



Support AT means that the custom firmware you are creating can be setup over a serial connection with the RUI3 AT commands.

What if we keep it Off?
How can we burn firmware then?

You can switch between the modes, even if you set Support AT off.

Details are in our RUI3 documentation

Actually after turning it Off, code size is reduced by 30% approximately.
Which is helping us to fit present code into flash.