Abstract— A practical, low-cost device is constructed to emulate
a computer keyboard and mouse through a single-switch
input. Most of the current single-switch computer interface
designs focus on simplified hardware implementations with a
major portion handled on the destination computer in software.
Our device called the PowerKeyboard provides an operating
system independent, hardware, single-switch interface for persons
of limited mobility or a form of paralysis. A combination of
scanning and scrolling techniques provide the available keystroke
and mouse control commands on an Liquid Crystal Display
(LCD). The triggering of a switch transmits the selected action or
executes a stored configuration command of the PowerKeyboard,
such as scrolling rate. In this paper, we present the design of the
PowerKeyboard and compare it to existing designs.