PREVENTION OF INCOMPATIBLE KEYBOARD SELECTIONS FROM BEING ENTERED DURING POWER INITIALIZATION

摘要

A control system for an apparatus wherein a keyboard for user selection has a plurality of first lines and a plurality of second lines coupled to a programmable microprocessor. The keyboard includes a plurality of switch elements arranged to selectively connect a particular one of the plurality of first lines to a particular one of the set of second lines. The control system is disabled while powering-up so that incompatible keyboard selections cannot be entered by the user.