| 摘要 |
PROBLEM TO BE SOLVED: To provide a signal processing circuit capable of performing an output having high resolution and high accuracy, even in the case of a rotary encoder having low resolution. SOLUTION: Four states are determined by a four-state determination block 2 from a combination of two output signals 1, 2 having different phases from the rotary encoder 1, and transition of each state is counted by a counter 3. Either of count-up and count-down of the counter 3 is discriminated by collating each state of the last time and this time. When detecting repeated transition between two adjacent states among four states of the rotary encoder 1 by an adjacent state transition determination block 4, count operation of the counter 3 is stopped. It is determined whether operation by a user of the rotary encoder 1 is being performed or not by a human operation determination block 5, based on a transition time during which the state of the rotary encoder 1 transits and/or existence of generation of transition over the three states, and the count operation of the counter 3 is executed in the case of the operation by the user. COPYRIGHT: (C)2009,JPO&INPIT
|
