Patent ID: 6061480
Filing Date: 2000-05-09
Classification: G06F

Abstract:
A coordinate input device comprising:a coordinate input section wherein a first conductive sheet for x-coordinate detection provided with electrodes on a pair of end edges and a second conductive sheet for y-coordinate detection provided with electrodes on a pair of end edges are superposed through a spacer so that respective pairs of electrodes intersect orthogonally with each other;an A/D converter for converting the signal from either of said first and second conductive sheets into a digital coordinate value;a processor connected to the A/D converter;a logic circuit different from the processor and connected to the processor for detecting variation of a predetermined voltage while the predetermined voltage is applied between one of said electrodes of said first conductive sheet and one of said electrodes of said second conductive sheet, the logic circuit generating an interrupt signal separate from an output of the A/D converter responsive to detecting the variation of the predetermined voltage, the logic circuit comprising a first inverter and a second inverter connected in series, each of said first and second inverters having an input and an output, the input of said first inverter configured to receive the variation in the predetermined voltage and the output of said second inverter configured to generate the interrupt signal,wherein the processor is configured to accept the digital coordinate value from said A/D converter in response to receiving the interrupt signal from said logic circuit.