| 摘要 |
PROBLEM TO BE SOLVED: To solve such problems that, when sound data such as waveform data meeting various playing forms, are stored in a hard disk, etc., and subjected to waveform synthesis, the musical tone waveforms rich in expression are obtained but when the hard disk, etc., are frequently accessed, access frequencies have to be lowered because of increased noise and shortened life. SOLUTION: Figure 30 is a state transition diagram of pages of the sound data to be stored into a cache memory. The sound data to be used in the future without fail are set in a FILLED state and the sound data currently under use are set in a LOCKED state. The sound data with which the use ends are set in a USED state. When the capacity of the cache memory falls short, the data are successively released (set in a FREE state) from the older of the pages in the USED state. When the data are assigned by the playing data, etc., the state is again returned to the FILLED state, but the data remaining with being released are returned again to be in the FILLED state when assigned by the playing data, etc. As a result, there is no more need for reading the sound data out of the hard disk, etc., relating to the sound data. |
