| 摘要 |
PURPOSE:To utilize sound generation channels efficiently without any waste by changing the utilization modes of a limited number of sound generation channels according to a play mode. CONSTITUTION:A key switch circuit 11 has an array of key switches corresponding to respective keys of a general keyboard and a key coder 12 detects the on-off state of each key switch of the key switch circuit 11 and outputs a key code KC indicating a key switch in an on state (pressed key). Further, the key coder 12 outputs a key-off inspection signal X utilized for key release detection and synchronizing pulses SY which are synchronized with the transmission timing of the key code KC. In this case, a division mode or common mode is specified for a play mode associatively with whether automatic accompaniment play is selected to perform key grouping and channel grouping associatively with whether a automatic accompaniment mode is selected or not. Consequently, limited number of keys and sound generation channels are utilized efficiently to realize an automatic accompaniment function. |
