The ON button turns on the ceiling mounted projector.  In a few rooms this button will switch on a monitor where a projector is not installed.

In some rooms the ON button will activate and lower an electrically operated screen.

When the ON button is pressed a warm up period begins which may disable other buttons until the warm up period is complete.

In most cases the projector input will default to the local PC.

The ON button will not switch on the local PC.  This need to be done using the button on the front of the PC.

There is a slight variation in rooms in North Campus and James Hehir building.  In these rooms the ON and OFF functions are on one button.  Press once for ON and press again for OFF.  However, there is a complication with the previously mentioned warm up and cool down times.  If the button has been pressed to turn ON, the toggle to the OFF function will not work until after the warm up time.   Likewise if it has been pressed to turn OFF, the toggle to the ON function will not work until after the cool down time.