Patent attributes
An active stylus includes a signal processing section. The signal processing section during operation in a first mode, while supplying a downlink signal DS1, obtained by modulating a pulse train signal with a pen pressure level P, to an electrode, determines whether it is necessary to switch to a second mode. The signal processing section during operation in the second mode, while supplying a downlink signal DS2, obtained by modulating a sine wave signal with the pen pressure level P, to the electrode, determines whether it is necessary to switch to the first mode. The signal processing section switches to operation in the second mode when determining that such is necessary, and switches to operation in the first mode when determining that such is necessary. The active stylus may be used with two position detection devices, one supporting only the first method and the other supporting only the second method.