| 摘要 |
PURPOSE:To generate a sound of free sound quality by setting the output frequency of a programmable counter for pitch to an integer multiple of the frequency of a target sound, equalizing the number of addresses of a waveform memory to the integer and using a counter having the scale equal to the integer as a waveform counter. CONSTITUTION:This sound generating device is equipped with a scale programmable counter 60 which has its frequency division ratio determined by scale ROM data and divides an oscillation frequency to a frequency N-times as high as that of a note to be outputted, a waveform ROM 61 stores with data obtained by converting one waveform of a sound into a digital value, and an N-scale counter 62 which counts the output of the scale programmable counter 60, and the number of addresses of the waveform ROM 61 is denoted as N. Therefore, waveform data stored in the waveform memory is outputted as the frequency of the target sound. Consequently, the waveform and envelope of the free sound and the strength of the sound are obtained to generate sounds of various quality, and rhythm sounds of different tone can be generated. |
