Patent ID: 7209868

Claim:
A signal monitoring method, including the steps of: (a) selecting one sensor of a group of sensors to communicate with a multiplexer; (b) determining whether signals generated by the selected one sensor are analog signals, or digital signals or pulse signals; (c) transmitting the generated signals to an analog to digital converter (ADC) if the generated signals are analog signals, and transmitting the generated signals to a micro control unit (MCU) if the generated signals are digital signals or pulse signals; (d) determining whether the generated signals input to the MCU are digital signals or pulse signals; (e) outputting the determined digital signals from the MCU to a monitor chip via a digital port of the MCU if the generated signals input to the MCU are digital signals, and outputting the determined pulse signals from the MCU to the monitor chip via a timer of the MCU if the generated signals input to the MCU are pulse signals; and (f) processing the digital signals or the pulse signals in the monitor chip.