| 摘要 |
<p>PURPOSE:To realize the long-distance shifts of a cursor with small number of operations of a track ball by changing the number of pulses generated for each rotation of the track ball in response to the rotational speed of the track ball. CONSTITUTION:When the rotation of a track ball 1 is detected by a rotation detecting part 2, this detection component is supplied to a pulse generating part 3 and converted into a pulse wave having the number of pulses corresponding to the rotation speed of the ball 1. The converted pulse wave is supplied to a sampling part 5 where the sampling cycle pulses received from an oscillator 6 are counted. When the count value of pulses exceeds a fixed level, an overflow signal is delivered from the part 5. Thus the number of pulses of said pulse wave are amplified by an amplifier 7 and supplied to a CRT 8. While the pulse wave is supplied directly to the CRT 8 when no overflow signal is delivered. A cursor is moved in response to the number of pulses of the pulse wave supplied to the CRT 8.</p> |
