+/**
+Driver for Uhlenbrock Intellibox. Uses the P50X binary protocol over RS232.
+
+Motorola decoders with 27 speed steps are supported by manually generating the
+commands necessary to reach the "half-steps". However, sending a rapid stream
+of speed changes to the same locomotive seems to cause excessive lag, so we
+cheat a bit; instead of sending the half-step command immediately, we send it
+with a 500ms delay, but only if no new set_loco_speed calls have occurred. As
+a downside from this accelerations and decelerations are still jerky.
+*/