Echo
From Sega Retro
Echo is a new sound-engine for the Sega Mega Drive created by Sik. It's Z80-based and allows full control over the sound hardware. Its purpose is to provide a free, open-source possibility to implement music and sound effects in programs, demos or games developed for the system. It is currently in alpha state, albeit functional for the most part.
Event list
Note on
| Event | Description |
|---|---|
| $00nn | Note on FM channel #1 |
| $01nn | Note on FM channel #2 |
| $02nn | Note on FM channel #3 |
| $04nn | Note on FM channel #4 |
| $05nn | Note on FM channel #5 |
| $06nn | Note on FM channel #6 |
| $08nn | Note on PSG channel #1 |
| $09nn | Note on PSG channel #2 |
| $0Ann | Note on PSG channel #3 |
| $0Bnn | Note on PSG channel #4 |
| $0Cnn | Note on PCM channel |
For $00 to $06 :
These events do a "note on" at the specified FM channel. The event is followed by a byte, which indicates which note to play. The value is as follows, where "octave" ranges from 0 to 7 and "semitone" ranges from 0 to 11:
32 * octave + 2 * semitone + 1
Links / Download
GitHub repository for Echo, including docs, source, binaries, etc.