| 摘要 |
<p>PURPOSE:To identify what kind of input member is used, by providing a means which discriminates an oscillation component. CONSTITUTION:When inputting is performed with an oscillation pen, a band-pass filter 31 in a frequency discrimination circuit 3 passes a component of 400kHz, and a high level d.c. signal is formed by a rectifier 32. Meanwhile, an output on a frequency discrimination circuit 4 side becomes a low level output because no component of 1kHz is included in the output of an oscillation sensor 7. Thus, since an input on one side of an AND gate 52 of a logic circuit 11 goes to a low level via an inverter 51, the terminal 61 of a CPU 6 goes to the low level, and the terminal 62 of the CPU 6 goes to a high level by receiving the high level signal of the frequency discrimination circuit 3. Also, when the inputting is performed with a finger F, since the frequency discrimination circuit 4 outputs the high level, and the frequency discrimination circuit 3 outputs the low level, the terminal 61 goes to the high level, and the terminal 62 to the low level. In such way, it is possible to identify input means with different input oscillation frequencies.</p> |
