Panasonic Switch-M12PWR Operation Manual page 194

Press "M." The command prompt changes to "Enter the power management
method>." Enter the management method. Press "0" to supply power to a newly
connected terminal by shutting down power supply from a low-priority port.
Press "1" to disable power supply to any newly connected terminals regardless of
the priority setting. When you complete the setting change, the display on the
screen is automatically updated.
Q Return to the previous menu.
194