| 摘要 |
The embodiment of the invention disclosed herein is directed to an electronic musical instrument of the keyboard type wherein the audio frequency signal information is derived from a multi-frequency generator formed by an electronic oscillator and a plurality of divider circuits, and wherein programmable divider circuits are associated with the various keys of the keyboard to generate associated tone signal information. The programmable divider circuits are formed on a large scale integrated circuit chip and enable alteration of the numerical divisor so that different tone signals can be obtained from the same electronic circuitry thereby enabling the same type of LSI chip to be used for many different circuit configurations. The LSI chip also provides a scanning circuit that scans an X-Y matrix switching arrangement to determine which one of a plurality of key switches is closed. The integrated circuit unit has a plurality of such programmable divisors arranged to be operated from the same frequency, preferably there being four programmable divisors to obtain a multitude of output audio signal frequencies. Actuation of a key switch, chord button switch, or foot pedal will enable gate circuit components to cause a signal transfer from a matrix array to a read-only-memory circuit, which, in turn, enables selected ones of the programmable divisors for developing the desired audio signal frequencies.
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