| 摘要 |
<p>PURPOSE:To set freely the full scale of output coordinates so that X and Y coordinates are independent of each other by providing a varying means for a clock frequency and selecting clock frequencies in X-coordinate detection and Y-coordinate detection independently of each other. CONSTITUTION:The approach or contact of an input pen 3 to or with an input surface 2 is detected and a driving signal is sent to a comparator 9 to turns on the output of an FF10 in a positive period. The detection signal of the input pen 3, on the other hand, turns off the output of the FF10 in the positive period. The output of the comparator 9 is sent to a monostable multivibrator 11 as well to detect its rising, and a pulse is sent to a terminal RST of a counter 14 to start a counter 14. Then, a clock from a voltage-controlled type oscillator VCO12 begins to be counted. The counting operation is carried on while the output of the FF10 is on and stopped when the output turns off. A clock frequency is set to a desired value by selecting the input voltage of the VCO12 through a voltage adjusting device 19.</p> |
