This variable reflects the status of the DPT/OPP jumper
on the board. This jumper controls the behavior of the
converter when a loss of signal is detected. When the
jumper is in the default OPP position, the loss of signal
detect on one port causes only the opposite port to be shut
down. In this case, Port Shutoff is said to be
disabled(2).
In the DPT (enabled(1)) position,
both ports are shut down.
Use of the DPT position is discouraged, as it is more likely
to lead to a signal loss condition from which the
converter is unable to recover.