| 摘要 |
<p>PURPOSE:To delete the effects of the hum and noise by selecting the maximum or minimum value of the detection data obtained within a sampling period or the average value data of said both values, and using the result as the data which decides the presence or absence of a contact. CONSTITUTION:When a touch sensor starts its actuation, the output pulses of a pulse generating circuit 11 are counted by a counter 16 after initialization. Then the counting of sampling time is started. While a pulse is delivered to a counter is response to a time constant which is decided by a resistance R and an electric capacitor C and then written to a RAM19. When the counter 16 produces a pulse after the prescribed counting is over, the count data is read out of the RAM19 to a CPU20. The maximum value is selected out of the count data and compared with the threshold valure to decide the presence of a contact of an operator. When the selected maximum value is larger than the threshold level, it is decided that the operator has a contact with a touch electrode 13. Then the number corresponding to the electrode 13 is delivered to another electronic device through an output port 22 of a computer 17. Thus a data processing arithmetic is carried out in response to the electrode 13.</p> |
