Arc_Seq.txt

Arcus Odyssey SFC Sequence Format
---------------------------------
Reverse-engineered by Valley Bell, May 2016


Sequence Header is at RAM offset 1820h


Sequence Header:
2 bytes - Sequence Size (0 in Arcus Odyssey?)
1 byte  - Tempo (seems to be in BPM)
0F*3 bytes - Track Headers

Track Header:
1 byte  - Track Flags (00 - not playing, 01 - playing (default))
2 bytes - Track Pointer




Note format:
1 byte - Note Height
1 byte - Tick Count til next note (chords are possible, so this can be 0)
1 byte - Tick Count til Note Stop
	-> if larger than NextNoteTick, when the note is held
1 byte - Volume (00 min .. 7F max)


Commands:
00-DF - Note
E0 xx - Delay of xx Ticks
E1 dd vv - Set Volume vv + Delay dd
E2 dd pp - Set Pan pp + Delay dd
E4 xx - Modulation On?
E5 dd pp tt - Modulation
	dd - delay before modulation starts
	pp - modulation depth (in 1/32 steps?)
	tt - modulation time
EC ii - Set Instrument ii
FD - Return/Pattern End



92 - Loop Start
93 tt - Loop End (tt - times to loop, 00 - infinite)
94 dd pp - Pitch Bend pp + Delay dd (12 semitones)
95 dd tt - Set Tempo tt + Delay dd (relative to initial tempo, 40h is 100%, 20h is 50% etc.)
97 dd xx - Set (another?) Volume vv + Delay dd
9B xx
A2 xx
A3 xx
AA xx xx - Reverb
AD xx
AE xx
AF xx xx
B2 xx
C8
F0
FD - Return/Pattern End
FE
FF - Track End


Note: All pointers are relative to the base offset, which is 4000 in Tales Of Phantasia and 3800 in Star Ocean.
The offset is located at 0854.