Active stylus

A method of determining user operation of an actuator, the method comprising:

• connecting the actuator to a state circuit having a first capacitor with a characteristic time constant that may assume each of a plurality of different magnitudes so that operation of the actuator operates to change the magnitude of the time constant from a first to a second magnitude of the plurality of magnitudes;
• and
• operating a popup and test (POPAT) circuit comprising a second capacitor to determine the magnitude of the characteristic time constant from the first capacitor in the state circuit.

A stylus comprising a stylus body and an actuator, the actuator enabling activation a plurality of switches within the stylus body to generate different magnitudes of voltages for a first capacitor, the stylus comprising:

• a state circuit embodying the first capacitor that is configured to experience a characteristic time constant that may assume a plurality of different magnitudes based on said activation of the plurality of switches via the actuator;
• and
• a popup and test (POPAT) circuit comprising a second capacitor operable to access the state circuit to acquire data useable to determine whether a user has operated the actuator to change the magnitude of the characteristic time constant.