US 4,046,047 A · Note selector circuit for electronic musical instrument

Abstract

An electric organ utilizes digital encoding and time division multiplexing to transfer both function selection and note selection information from manually operable switches to respective memories, and to simultaneously produce tone signals corresponding to stored note selection information. A single encoding circuit encodes in binary form the function and note selection information during successive scanning periods established by a single multiplexing circuit. A plurality of stored note codes are transferred on a time division multiplexing basis to a note selector which selectively produces all of the selected tone signals, on one output in multiplexed form. The tone signals are demultiplexed to generate a corresponding plurality of tone signal outputs. An octave selection circuit which is responsive to a part of each note code selectively reduces the frequency of the demultiplexed tone signals. In response to storage of the code for a memory function, the note code memory operates to maintain note codes in storage after deactuation of the switches corresponding thereto until it is updated with new note codes in response to selection of a new set of notes.

Claims18

Dependent claims

In an electronic musical instrument having means for providing input signals carrying note selection and note sequence function selection information, means for generating tones, and means for controlling the tone generating means in accordance with note and note sequence function selection information supplied thereto, an improved circuit for supplying information to the control means, comprising:

means for multiplexing together, on a time division basis, the note and note sequence function selection input signals:
an encoding circuit responsive to the multiplexed signals for providing binary coded signals respectively representative of the note selection and function selection information carried thereby;
storing means including a note memory for storing said note selection codes and a function memory for storing said function selection codes;
and demultiplexing means including means responsive to the code signals and said multiplexing means for respectively enabling the note memory and the function memory during the time divisions that said note selection signals and function selection signals are being applied to the encoding logic input means whereby the note selection codes and the function selection codes representative of the information carried by the multiplexed signals are respectively stored in said note and function memories.

1 more element

In an electronic musical instrument having an input signal providing means including a note input circuit for providing note selection input signals and a note sequence function input circuit for providing note sequence function selection input signals, said signals respectively carrying note selection and note sequence function selection information, means for generating tones, and means for controlling the tone generating means in accordance with note and note sequence function selection information supplied thereto, an improved circuit for supplying the information to the control means, comprising:

means for multiplexing together the note and note sequence function selection input signals including means for periodically successively enabling said input circuits one at a time, each input circuit capable of providing signals on selected one of a plurality of outputs thereof when enabled;
an encoding logic circuit responsive to the multiplexed signals for providing binary coded signals respectively representative of the note and function selection information carried thereby, said encoding logic means having a plurality of inputs respectively connected with the plurality of outputs of both said input circuits and including means for successively scanning the inputs thereof for input signals during each input circuit enablement period,
means for generating both a note code and note sequence function code for each input as it is scanned and code selecting means operative when an input is scanned having an input signal thereon;
and means for demultiplexing the input signals including
a memory having note code storage means connected with the note code generating means, and having a plurality of note code storage elements for storing the note codes of a corresponding plurality of selected notes, said plurality being less than the number of outputs of the note input circuit, whereby different storage elements store the codes of different notes at different times, and
whereby the tone generating control means performs its control function in accordance with the stored codes.

3 more elements

Dependencies are inferred from the claim text.

Note selector circuit for electronic musical instrument

Life of this patent

Note selector circuit for electronic musical instrument

Life of this patent

Abstract

Claims18