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 |
{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 | Unknown. | Seems to do nothing based on the code. | ||
| 81 ... 87 |
{OpCode[1]} OpCode: one byte with range 0x81 through 0x87. 0x81 = Close Voice 1, 0x87 = Close Voice 7. |
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:
|
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:
|
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:
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:
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 | |||
| D1 | JASSeqParser::cmdWritePort | |||
| 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 | |||
| 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 | |||
| 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)