BMS (File Format)

File Format

BMS files are Binary Music Sequences that store commands for the audio engine to play notes, similar to the MIDI file format.

Data

BMS files contain raw instructions for the audio engine. There are no headers or filesize checks. Each instruction (OpCode) stands for its own function in the engine. The following table lists all JAudio2 OpCodes that have functions in SMG2:

OpCode	Function (SMG/SMG2)	Usage	Example	Description
00 01 02 ... 7D 7E 7F	JASSeqParser::parseNoteOn	{OpCode[1]} {Voice[1]} {Velocity[1]} OpCode: one byte with range 0x00 through 0x7F. 0x00 = C-1, 0x3C = C4 (middle C), 0x7F = G9. Voice: one byte with range 0x01 through 0x07 (needs testing/verification). Each Voice can only hold one Note. Velocity: one byte with range 0x00 through 0x7F. 0x00 = 0, 0x7F = 127. If the Voice is not 1 - 7, the game will treat this note as a Midi Gate note, and will expect a 4th value that is one or more bytes with range 0x00 through 0xFF. If the leading byte is 0x80 (bit 7 = 1) or greater, another following byte will be taken into account. It is unknown what effects this has on the output.	64 02 68 64: Key E4 02: Voice 2 68: Velocity 104	Starts playing a Note with the previously defined Instrument (see E1, E2 and E3).
80	JASSeqParser::cmdWaitByte			Seems to do nothing based on the code.
81 ... 87	JASSeqParser::parseNoteOff	{OpCode[1]} OpCode: one byte with range 0x81 through 0x87. 0x81 = Close Voice 1, 0x87 = Close Voice 7.	81: Stop voice ID 1	Stops playing a Note.
88 ... 8F	Unknown
90 ... 9F	Unknown
A0	NULL
A1	NULL
A2	NULL
A3	NULL
A4	NULL
A5	NULL
A6	NULL
A7	NULL
A8	NULL
A9	NULL
AA	NULL
AB	NULL
AC	NULL
AD	NULL
AE	NULL
AF	NULL
B0	Extended Opcode Indicator	See B000 or B001.
B1	JASSeqParser::cmdNoteOn
B2	JASSeqParser::cmdNoteOff
B3	JASSeqParser::cmdNote
B4	JASSeqParser::cmdSetLastNote
B5	NULL
B6	NULL
B7	NULL
B8	JASSeqParser::cmdParamE	{OpCode[1]} {Target[1]} {Parameter[1]} OpCode: one byte, B8. Target: one byte with range 0x00 through 0x03. Parameter: one byte with range 0x00 through 0xFF (Int8), whichs purpose depends on the target: Target 0: Volume. 0x7F = Full volume (100%), 0x00 = Silent (0%). 0x80 through 0xFF are treated the same as silence (0%). Target 1: Pitch. Adding one (0x01) or subtracting one (0xFF) increases/decreases pitch by one key, like from D#4 to E4. Target 2: Reverb. 0x7F = Strong reverb, 0x00 = no reverb. 0x80 through 0xFF are treated the same as no reverb. Target 3: Panning. 0x7F = right channel, 0x00 = center, 0x80 = left channel.	B8 00 64 B8: OpCode 00: Target (Volume) 64: ~78% volume	Allows different operations onto the music track
B9	JASSeqParser::cmdParamI	{OpCode[1]} {Target[1]} {Parameter[2]} OpCode: one byte, B9. Target: one byte with range 0x00 through 0x03. Parameter: two bytes with range 0x0000 through 0xFFFF (Int16), whichs purpose depends on the target: Target 0: Volume. 0x7FFF = Full volume (100%), 0x0000 = Silent (0%). 0x8000 through 0xFFFF are treated the same as silence (0%). Target 1: Pitch. Adding one (0x0100) or subtracting one (0xFF00) increases/decreases pitch by one key, like from D#4 to E4. Values inbetween can be used for fine-tuning. Target 2: Reverb. 0x7FFF = Strong reverb, 0x0000 = no reverb. 0x8000 through 0xFFFF are treated the same as no reverb. Target 3: Panning. 0x7FFF = right channel, 0x0000 = center, 0x8000 = left channel.	B9 01 04 00 B9: OpCode 01: Target (Pitch) 04 00: Pitch of 4 keys	Allows different operations with higher precision onto the music track
BA	JASSeqParser::cmdParamEI	{OpCode[1]} {Target[1]} {Parameter[1]} {Fade time[2]} OpCode: one byte, BA. Target: one byte with range 0x00 through 0x03. Parameter: one byte with range 0x00 through 0xFF (Int8), whichs purpose depends on the target: Target 0: Volume. 0x7F = Full volume (100%), 0x00 = Silent (0%). 0x80 through 0xFF are treated the same as silence (0%). Target 1: Pitch. Adding one (0x01) or subtracting one (0xFF) increases/decreases pitch by one key, like from D#4 to E4. Target 2: Reverb. 0x7F = Strong reverb, 0x00 = no reverb. 0x80 through 0xFF are treated the same as no reverb. Target 3: Panning. 0x7F = right channel, 0x00 = center, 0x80 = left channel. Fade time: two bytes with range 0x0000 through 0xFFFF. The amount of time in ticks until the Parameter value is met.	BA 02 22 01 68 BA: OpCode 02: Target (Reverb) 22: Reverb of strength 34 01 68: 360 Ticks	Allows different operations with fade time onto the music track
BB	JASSeqParser::cmdParamII	{OpCode[1]} {Target[1]} {Parameter[2]} {Fade time[2]} OpCode: one byte, BB. Target: one byte with range 0x00 through 0x03. Parameter: two bytes with range 0x0000 through 0xFFFF (Int16), whichs purpose depends on the target: Target 0: Volume. 0x7FFF = Full volume (100%), 0x0000 = Silent (0%). 0x8000 through 0xFFFF are treated the same as silence (0%). Target 1: Pitch. Adding one (0x0100) or subtracting one (0xFF00) increases/decreases pitch by one key, like from D#4 to E4. Values inbetween can be used for fine-tuning. Target 2: Reverb. 0x7FFF = Strong reverb, 0x0000 = no reverb. 0x8000 through 0xFFFF are treated the same as no reverb. Target 3: Panning. 0x7FFF = right channel, 0x0000 = center, 0x8000 = left channel. Fade time: two bytes with range 0x0000 through 0xFFFF. The amount of time in ticks until the Parameter value is met.	BA 03 7F FF 02 00 BB: OpCode 03: Target (Panning) 7F FF: Panned to right channel 02 00: 512 Ticks	Allows different operations with higher precision and fade time onto the music track
BC	NULL
BD	NULL
BE	NULL
BF	NULL
C0	NULL
C1	JASSeqParser::cmdOpenTrack	{OpCode[1]} {TrackNumber[1]} {Pointer[3]} OpCode: one byte, C1. TrackNumber: one byte with range 0x00 through 0x0F. 0x00 = Track 0, 0x0F = Track 15. Pointer: three bytes with range 0x000000 through 0xFFFFFF. Defines an offset in the file.	C1 04 05 B4 73 C1: OpCode 04: Track 4 05 B4 73: Offset	Creates a Track which can play Notes. Track 15 is usually reserved for Yoshi Drums.
C2	JASSeqParser::cmdCloseTrack
C3	JASSeqParser::cmdCall	{OpCode[1]} {Pointer[3]} OpCode: one byte, C3. Pointer: three bytes with range 0x000000 through 0xFFFFFF. Defines an offset in the file.	C3 00 00 40 C3: OpCode 00 00 40: Offset	Redirects execution to the defined offset. Execution can return with C5.
C4	JASSeqParser::cmdCallF
C5	JASSeqParser::cmdRet	{OpCode[1]} OpCode: one byte, C5.		Returns redirected execution (like from C3) to the initial call.
C6	JASSeqParser::cmdRetF
C7	JASSeqParser::cmdJmp	{OpCode[1]} {Pointer[3]} OpCode: one byte, C7. Pointer: three bytes with range 0x000000 through 0xFFFFFF. Defines an offset in the file.	C7 08 02 34 C7: OpCode 08 02 34: Offset	Redirects execution to the defined offset, used for Loops.
C8	JASSeqParser::cmdJmpF
C9	JASSeqParser::cmdJmpTable
CA	JASSeqParser::cmdCallTable
CB	JASSeqParser::cmdLoopS
CC	JASSeqParser::cmdLoopE
CD	NULL
CE	NULL
CF	NULL
D0	JASSeqParser::cmdReadPort	{OpCode[1]} {Source[1]} {Destination[1]} Opcode: One byte, D0 Source: One byte, 0-15 , source port Destination: One byte, 0-32, destination register		Imports the value from sequence port Source and writes it to destination register 'Destination', the value is also written to register 3
D1	JASSeqParser::cmdWritePort	{OpCode[1]} {Source[1]} {Destination[1]} Opcode: One byte, D1 Source: One byte, source register, 0-32 Destination: One Byte, destination port, 0-15		Writes the value in register 'Source' and saves it to register 3, as well as port 'Destination'
D2	JASSeqParser::cmdCheckPortImport
D3	JASSeqParser::cmdCheckPortExport
D4	JASSeqParser::cmdParentWritePort
D5	JASSeqParser::cmdChildWritePort
D6	JASSeqParser::cmdParentReadPort
D7	JASSeqParser::cmdChildReadPort
D8	JASSeqParser::cmdRegLoad	{OpCode[1]} {Setting[1]} {Unknown[1]} {Variable[1]} OpCode: one byte, D8. Setting: one byte with unknown range. Different bytes will trigger different effects: - 0x62: set PPQN (seen in BMS) - 0x6B: set PPQN (seen in SC) Unknown: one byte with unknown range and purpose. Variable: one byte with different range and purpose depending on the Setting byte.	D8 62 00 78 D8: OpCode 62: set PPQN 00: Unknown 78: PPQN 120	Different purposes.
D9	JASSeqParser::cmdReg
DA	JASSeqParser::cmdReg
DB	JASSeqParser::cmdRegUni
DC	JASSeqParser::cmdRegTblLoad	{OpCode[1]} {AccessMode[1]} {Destination[1]} {Offset[3]} {Index[1]} OpCode: One Byte, 0xDC AccessMode: Determines how the sequence accesses the table. Destination: 24-bit offset of table Index: Register target index into table
DD	NULL
DE	NULL
DF	NULL
E0	JASSeqParser::cmdTempo	{OpCode[1]} {Unknown[1]} {BPM[1]} OpCode: one byte, E0. Unknown: one byte with unknown range and purpose. BPM: one byte with range 0x00 through 0xFF. 0x78 = 120, F0 = 240.	E0 00 90 E0: OpCode 00: Unknown 90: BPM 144	Defines the tempo (playback speed) of the BMS file.
E1	JASSeqParser::cmdBankPrg	{OpCode[1]} {Bank[1]} {Program[1]} OpCode: one byte, E1. Bank: one byte with range 0x00 through 0xFF. This byte represents a WSYS ID. Program: one byte ranging from 0x00 through 0xFF. This byte represents a LIST entry in the IBNK belonging to the defined WSYS ID.	E1 01 0F E1: OpCode 01: WSYS ID 1 0F: IBNK LIST entry 15 (01 0F is the percussion set for Yoshi Drums)	Defines the Instrument to be used in a Track.
E2	JASSeqParser::cmdBank	{OpCode[1]} {Bank[1]} OpCode: one byte, E2. Bank: one byte with range 0x00 through 0xFF. This byte represents a WSYS ID.	E2 53 E2: OpCode 53: WSYS ID 83 (This bank holds sounds for Megahammer)	Defines the WSYS/IBNK whose sounds are to be used in a Track.
E3	JASSeqParser::cmdPrg	{OpCode[1]} {Program[1]} OpCode: one byte, E3. Program: one byte with range 0x00 through 0xFF. This byte represents a LIST entry in the IBNK belonging to the defined WSYS ID.	E3 0B E3: OpCode 0B: IBNK LIST entry 11 (In relation to Megahammer, this Program holds movement related sounds)	Defines the Keyboard which holds more specific sounds to an IBNK.
E4	NULL
E5	NULL
E6	NULL
E7	JASSeqParser::cmdEnvScaleSet
E8	JASSeqParser::cmdEnvSet
E9	JASSeqParser::cmdSimpleADSR	{OpCode[1]} {Attack[2]} {Sustain[2]} {Decay[2]} {Amplitude[2]} {Release[2]} OpCode: one byte, E9. Attack: two bytes with range 0x0000 through 0x7FFF. Define the duration of fade-in in ticks. Sustain: two bytes with range 0x0000 through 0x7FFF. Define the duration for how long the wave is kept at maximum amplitude in ticks. Decay: two bytes with range 0x0000 through 0x7FFF. Define the duration of fade between maximum and controlled amplitude in ticks. Amplitude: two bytes with range 0x0000 through 0x7FFF. Define the volume of the wave for the 2nd sustain duration. Release: two bytes with range 0x0000 through 0x7FFF. Define the duration of fade-out in ticks. If Amplitude is set to 0x7FFF, Sustain and Decay won't have an audible effect to the wave. The Attack, Decay and Release operations affect the volume of the wave linearly.	E9 00 80 01 00 00 80 5F FF 00 3C E9: OpCode 00 80: Attack (fade-in) for 128 ticks 01 00: Sustain for 256 ticks 00 80: Decay for 128 ticks 5F FF: Amplitude of 75% compared to maximum 00 3C: Release (fade-out) for 60 ticks	Perform ADSR operations on a key. Must be placed before the actual key presses. See this image for a visual representation of the ADSR operations.
EA	JASSeqParser::cmdBusConnect	{OpCode[1]} {Unknown[1]} {Unknown[1]} {Unknown[1]} OpCode: one byte, EA. Unknown: one byte with unknown range and purpose.	EA 00 FF FF EA: OpCode 00: Unknown FF: Unknown FF: Unknown	Unknown purpose, only seen in SC.
EB	JASSeqParser::cmdIIRCutOff
EC	JASSeqParser::cmdIIRSet
ED	JASSeqParser::cmdFIRSet
EE	NULL
EF	NULL
F0	JASSeqParser::cmdWait	{OpCode[1]} {WaitTime[n]} OpCode: one byte, 0xF0. WaitTime: one or more bytes with range 0x00 through 0xFF. If the leading byte is 0x80 (bit 7 = 1) or greater, another following byte will be taken into account. Time is measured in ticks here.	F0 60 (96 Ticks) F0 81 56 (214 Ticks) F0 83 81 30 (49328 Ticks)	Creates a delay, used to define the length of a Note or gap between Notes.
F1	JASSeqParser::cmdWaitByte	{OpCode[1]} {WaitTime[1]} Waits for WaitTime ticks
F2	NULL
F3	JASSeqParser::cmdSetIntTable
F4	JASSeqParser::cmdSetInterrupt
F5	JASSeqParser::cmdDisInterrupt
F6	JASSeqParser::cmdRetI
F7	JASSeqParser::cmdClrI
F8	JASSeqParser::cmdIntTimer
F9	JASSeqParser::cmdSyncCPU
FA	NULL
FB	NULL
FC	NULL
FD	JASSeqParser::cmdPrintf	{OpCode[1]} {Message[n]} {NullTerminator[1]} OpCode: one byte, FD. Message: ASCII string of undefined length, ending with \n. NullTerminator: one byte, 00.	FD 48 65 6C 6C 6F 5C 6E 00 FD: OpCode 48 65 6C 6C 6F 5C 6E: "Hello\n" 00: Null-terminator	Prints a specified message to OSReport.
FE	JASSeqParser::cmdNop
FF	JASSeqParser::cmdFinish	{OpCode[1]} OpCode: one byte, 0xFF.		Stops execution of a Track.
B000	NULL
B001	JASSeqParser::cmdDump

Tools

BMS_DEC (converts BMS to MIDI)
JaiSeqX (playback for JAudio1 and JAudio2 BMS files)