Hi,
We published a documentation on how to add native calls in your monolithic application [1] through SNI [2]. The native call manages a LED.
The MicroEJ Team
[1] https://github.com/MicroEJ/How-To/tree/master/SNI-LED
[2] SNI-GT - Safe Native Interface for GreenThread Context @
http://e-s-r.net/specifications/index.html