VS1033 - MP3/AAC/WMA/MIDI AUDIO CODEC - VLSI Solution

VLSISolution yVS1033cVS1033C8. FUNCTIONAL DESCRIPTION8.2.7 Supported MIDI FormatsGeneral MIDI and SP-MIDI format 0 files are played. Format 1 and 2 files must be converted to format0 by the user. The maximum simultaneous polyphony is 40. Actual polyphony depends on the internalclock rate (which is user-selectable), the instruments used, whether the reverb effect is enabled, andthe possible global postprocessing effects enabled, such as bass enhancer, treble control or EarSpeakerspatial processing. The polyphony restriction algorithm makes use of the SP-MIDI MIP table, if present.36.86 MHz (3.0× input clock) achieves 16-26 simultaneous sustained notes. The instantaneous amountof notes can be larger. 36 MHz is a fair compromise between power consumption and quality, but higherclocks can be used to increase the polyphony.Reverb effect can be controlled by the user. In addition to reverb automatic and reverb off modes, 14different decay times can be selected. These roughly correspond to different room sizes. Also, eachmidi song decides how much effect each instrument gets. Because the reverb effect uses about 4 MHz ofprocessing power the automatic control enables reverb only when the internal clock is at least 3.0×.When EarSpeaker spatial processing is active, MIDI reverb is not used.New instruments have been implemented in addition to the 36 that are available in VS1003. VS1033now has unique instruments in the whole GM1 instrument set and one bank of GM2 percussions.Version 1.00, 2008-02-01 30