Playing around with newly received KRC4 NAs, R3100 Ultras, just noticed that "Startup Mode" (the wonderful software safety jumper) works if X11 is plugged in or not , also regardless of what signals are present on X11 (X11 is terminated and active, the robot is not seeing a no load on the wires).
Anybody else notice this on new(er) 8.3 KRC4s ??