Abstract: When an ending switch is operated on an electronic musical instrument while an automatic accompaniment is being produced, the pattern data of an automatic ending accompaniment is read out from a memory. Corresponding accompaniment sounds are generated from a loudspeaker to obtain the automatic ending.

Abstract: When the fill-in key and synchro start key are operated, an output of an inverter causes an AND gate to inhibit the resetting of a flip-flop by an output of a bar clock generator. In consequence, a fill-in rhythm is sounded continuously with a pattern selector driven by the set output of the flip-flop. When an accompaniment play key is operated at a desired instant in this situation, an output of a key depression detection circuit is fed through an AND gate and an OR gate to the reset input terminal of the flip-flop. As a result, the address of a ROM designated by the pattern selector, is changed to start sounding of normal rhythm.

Abstract: A key signal is supplied through an I/O port to a chord discriminating section of one electronic musical instrument, which generates corresponding accompaniment tone data. The accompaniment tone data is transferred through the I/O port to a tone signal generator of a different electronic musical instrument without auto-play accompaniment function, whereby accompaniment tone is generated from the different electronic musical instrument.

Abstract: Under the presence of an internally generated mandolin clock (MDN) or an externally generated mandolin clock (MDN'), an envelope clock (ENV-CLK) obtained in accordance with a lower bit output having three-bit signals (including the LSB) is supplied through AND gates to an envelope counter. The counter is set in an up count state in response to an output from a flip-flop set in response to a key on pulse. When a carry signal is generated by the envelope counter, the counter is set in a down count state. In the latter case, the fourth-bit signal from the LSB of the output from the binary counter is gated through the AND gate. The envelope counter counts down the envelope clock (ENV-CLK) having a period twice that of the envelope clock (ENV-CLK) in the up count state.