Just finished looking at countless schematics and the FCOM. Jetboy has it correct main gear compressed from LGCIU and reverse selected from FADEC. Main gear compressed, which could come from Strut Compression or Bogie Tilt in this case (reverse) coming from Bogie Tilt according to my reading of the LGCIU schematic.
Yes the picture depicts a Brass ground point used for grounding static. I don't know why but most Aircraft types and people that I've encountered refer to ground as opposed to earth, I guess it's the American influence.
