Code example without Marlin?

[imperator-maximus]

Hi, I ordered some S42B V1.1 and SKR V1.4/V1.4 Turbo board. I want to use these in a project which does not have any connection to a 3D printer or something similar.

As I see everything here is made so for 3D printer use with Marlin firmware. I already found examples about how to implement custom functions for custom G-Code commands in Marlin.
But I am wondering how it would be possible to use that board + that closed loop S42B just in a plain example without Marlin overhead?
In both scenarios (custom G-Code command) or plain code: how to use these motors (Wifi, display,...)?

Thank you!

[imperator-maximus]

In my opinion the interface has to be improved before which can be made via custom firmware. So with this it would be possible to access it via UART only and any board can be used. SKR V1.4/V1.4 is not very helpful here.