Patent ID: 7561118

Claim:
A method for controlling a circuit, the method comprising: providing a multiplexer circuit comprising user-actuable switches, light-emitting elements associated with the user-actuable switches, and interconnects shared by the user-actuable switches and the light-emitting elements; and controlling the multiplexer circuit in a repeating cycle divided into multiple time slots, the controlling comprising: pulsing a selected light-emitting element during a first time slot of the repeating cycle, and reading the state of a selected switch during a second time slot different from the first time slot, such that the pulsing and reading are repeatedly performed during the controlling in an alternative manner and the selected light-emitting element is powered for only a portion of each repeating cycle to enable reading the state of the selected switch using the shared interconnects while the selected light-emitting element is not powered during the repeating cycle.