| 摘要 |
<p>PURPOSE:To reduce a circuit and to reduce a load for a host controller by providing a means selecting a frequency from a rectangular waveform and an amplitude picked up from a input wave and a means dividing a control signal by kind classification. CONSTITUTION:By a frequency extracting part 1, the rectangular wave being a frequency component in the input wave is outputted. By a level extracting part 2, the amplitude in the input wave is compared with a fixed amplitude value and the compared result is outputted. By a CPU 3, from the rectangular wave inputted from the frequency extracting part 1 and the compared result inputted from the level extracting part 2, the frequency is selected as occasion demands and in each frame, the kind of the waveform is outputted to the host controller, and the amplitude and the rectangular wave are outputted under the control of the host controller. By a frequency selection part 3A, a frequency selected result is outputted from the inputted rectangular wave and the compared result. By a sampling part 3B, the waveform is selected by comparing the selected result obtained from the selection part 3A with a pattern in the control signal according to timing in each frame.</p> |
