So I'm working on building a Prusa i3 MK3 clone and all's gone well so far but when I make edits to the firmware and reupload it, the printer doesn't seem to be getting it. Like I changed the software endstops to new values in the code, recompiled it and reuploaded it, but when I use `M211` the printer still reports its old endstop values. 
Also, it seems to only be able to home to the minimum, not the maximum (not the biggest deal). 

Any advice on how to get the printer to recognize its new boundaries/is there a way to just set it with a G-code?