Header
------
Pos	Len	Description
00	04	"MMU1" signature
04	01	song tempo
05	01	global transposition
06	0B	[ignored]
10	??	track data (12h tracks)

Track Data
----------
2 bytes - track length (includes this value)
1 byte  - track ID
1 byte  - unused (RCP rhythm mode?)
1 byte  - channel ID (FF = none)
1 byte  - track transposition (low 7 bits = transpose, 80h = special)
1 byte  - Start Tick (example: delay track by N ticks)
1 byte  - channel muted (only bit 0 is important)
?? bytes - sequence data


Known commands (RCP-style):
00..7F - note
91 00 aa bb - ?? (used by tbs98\MSC.FMX songs 79, 84)
              In RCP, this is "User SysEx", however it is impossible to what parameter it was supposed to be used with.
DD 00 hh mm - set Roland Base Address (hh = high address, mm = mid address)
DE 00 ll vv - send Roland SysEx Parameter (ll = low address, vv = value)
DF 00 mm vv - set Roland Device (mm = model ID, vv = device ID)
E6 00 cc ## - set MIDI channel to cc
E7 00 tt mm - set song tempo (tt = 40h -> 100%, mm = 0 -> instant change, mm = 1 -> ignored)
EA 00 vv ## - MIDI channel aftertouch
EB 00 cc vv - MIDI control change cc, value vv
EC 00 pp 00 - MIDI patch change pp
EE 00 ll mm - MIDI pitch bend mmll
F6 00 xx xx - comment
F7 00 xx xx - continuation
F8 00 00 00 - Loop End
F9 01 00 00 - Loop Start
FC ## ll mm - repeat previous measure
              Plays the measure at offset mmll. The actual file offset is:
                  OfsTrackStart + (mmll & 0FFFCh) - 0024h
FD ## ## ## - measure end (The first parameter seems to be 0 or 1, but the driver ignores all parameters.)
FE ## ## ## - track end
FF ## ## ## - track end
