For solving the defect that a hardware clock of a serial peripheral interface bus has to cooperate with slower software-simulated clocks used by a microprocessor while applying serial peripheral interface buses on a large-scale touch panel, a programmable logic device is used as a bridge of communicating information between the micro processor and sensors. Therefore, the microprocessor no longer has to take execution time to simulate serial peripheral interface buses by software, and is able to program hardware clocks of each of the serial peripheral interface buses according to speed requirements of different sensors, so that sensing signals of a plurality of sensors may be integrated on a touch device having the large-scale touch panel, and a processing speed of the touch device in processing the sensing signals may be optimized as a result.