Acknowledgement

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This document was originally distributed in text format by
The International MIDI Association.

I have updated it and added new Appendices.

© Copyright 1999 David Back.


EMail: david@csw2.co.uk
Web:   http://www.csw2.co.uk

THIS DOCUMENT MAY BE FREELY COPIED IN WHOLE OR IN PART
PROVIDED THE COPY CONTAINS THIS ACKNOWLEDGEMENT.
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SEP-OCT 2018 github.com/tfwio/smfio

- Append/clarify GM2 info/tables
- Format to PDF (mmd->pandoc->xelatex->pdf)

MMA Trademark Policies

The term “MIDI”, the treatment of “MIDI” as used in the MIDI Association¹ and MMA logos, and various other logos are all trademarks of the MMA and must only be used as directed below.

MIDI Trademark and Logo

“MIDI” refers to a series of copyrighted specifications (“MMA Specifications”) maintained and published by MMA (and AMEI in Japan). Products, services, and technologies (“Products”) based on the MMA Specifications are known, as “MIDI Products”, “MIDI Files”, etc. MMA has common law and other exclusive rights for the use of the term “MIDI” in conjunction with MMA Specifications and associated Products.

1. The term “MIDI” (whether alone or in conjunction with other terms or modifiers) may be used by other parties (a) in reference to Products that are compliant with MMA Specifications, and/or (b) in the name of a company that provides such Products, except as excluded by paragraph 2 (below). Permitted uses do not need to be approved in advance by MMA. Conversely, any use in reference to non-compliant Products and/or by a company that does not produce Products compliant with MMA Specifications is NOT ALLOWED.

2. The use of the term “MIDI” in combination with other terms or words to identify Products that while compliant with MMA Specifications also have additional functions that are not set forth in an MMA Specification is likely to lead people to expect that MMA has standardized said functions which is deceptive trade practice, false advertising, and unfair competition, and such uses are not allowed by MMA. Only MMA may use the term “MIDI” in conjunction with the naming of a technology or specification.

3. The treatment (font and design) of the term “MIDI” which appears in the MMA and TMA Logo (see web page header, above) and in logos licensed by MMA may not be used by any party without a license from MMA. At this time the only licenses that are available are listed below.

Logo Licenses

The following Logos are available to MMA Members for use with compliant products.

General MIDI Logos

• SMF Logos
• DLS Logos
• XMF Logos

Introduction

This document details the structure of MIDI Files. The purpose of MIDI Files is to provide a way of interchanging time-stamped MIDI data between different programs on the same or different computers. One of the primary design goals is compact representation, which makes it very appropriate for disk-based file format, but which might make it inappropriate for storing in memory for quick access by a sequencer program.

MIDI Files contain one or more MIDI streams, with time information for each event. Song, sequence, and track structures, tempo and time signature information, are all supported. Track names and other descriptive information may be stored with the MIDI data. This format supports multiple tracks and multiple sequences so that if the user of a program which supports multiple tracks intends to move a file to another one, this format can allow that to happen.

The specification defines the 8-bit binary data stream used in the file. The data can be stored in a binary file, nibbilized, 7-bit-ized for efficient MIDI transmission, converted to Hex ASCII, or translated symbolically to a printable text file. This spec addresses what’s in the 8-bit stream. It does not address how a MIDI File will be transmitted over MIDI.

Sequences, Tracks, Chunks: File Block Structure

In this document, bit 0 means the least significant bit of a byte, and bit 7 is the most significant.

Variable Length Quantity

Some numbers in MIDI Files are represented in a form called VARIABLE-LENGTH QUANTITY. These numbers are represented 7 bits per byte, most significant bits first. All bytes except the last have bit 7 set, and the last byte has bit 7 clear. If the number is between 0 and 127, it is thus represented exactly as one byte.

Some examples of numbers represented as variable-length quantities:

00000000 → 00
00000040 → 40
0000007F → 7F
00000080 → 81 00
00002000 → C0 00
00003FFF → FF 7F
00004000 → 81 80 00
00100000 → C0 80 00
001FFFFF → FF FF 7F
00200000 → 81 80 80 00
08000000 → C0 80 80 00
0FFFFFFF → FF FF FF 7F

The largest number which is allowed is 0FFFFFFF so that the variable-length representations must fit in 32 bits in a routine to write variable-length numbers. Theoretically, larger numbers are possible, but 2 x 10^8^ 96^ths^ of a beat at a fast tempo of 500 beats per minute is four days, long enough for any delta-time!

Files

To any file system, a MIDI File is simply a series of 8-bit bytes. On the Macintosh, this byte stream is stored in the data fork of a file (with file type ‘MIDI’), or on the Clipboard (with data type ‘MIDI’). Most other computers store 8-bit byte streams in files.

Chunks

MIDI Files are made up of -chunks-. Each chunk has a 4-character type and a 32-bit length, which is the number of bytes in the chunk. This structure allows future chunk types to be designed which may be easily be ignored if encountered by a program written before the chunk type is introduced. Your programs should EXPECT alien chunks and treat them as if they weren’t there.

Each chunk begins with a 4-character ASCII type. It is followed by a 32-bit length, most significant byte first (a length of 6 is stored as 00 00 00 06). This length refers to the number of bytes of data which follow: the eight bytes of type and length are not included. Therefore, a chunk with a length of 6 would actually occupy 14 bytes in the disk file.

This chunk architecture is similar to that used by Electronic Arts’ IFF format, and the chunks described herein could easily be placed in an IFF file. The MIDI File itself is not an IFF file: it contains no nested chunks, and chunks are not constrained to be an even number of bytes long. Converting it to an IFF file is as easy as padding odd length chunks, and sticking the whole thing inside a FORM chunk.

Chunk Types

MIDI Files contain two types of chunks: header chunks and track chunks. A -header- chunk provides a minimal amount of information pertaining to the entire MIDI file. A -track- chunk contains a sequential stream of MIDI data which may contain information for up to 16 MIDI channels. The concepts of multiple tracks, multiple MIDI outputs, patterns, sequences, and songs may all be implemented using several track chunks.

A MIDI File always starts with a header chunk, and is followed by one or more track chunks.

MThd <length of header data>
<header data>
MTrk <length of track data>
<track data>
MTrk <length of track data>
<track data>
…

Chunk Descriptions

Header Chunks

The header chunk at the beginning of the file specifies some basic information about the data in the file.
Here’s the syntax of the complete chunk:

<Header Chunk> = <chunk type><length><format><ntrks><division>

As described above, <chunk type> is the four ASCII characters ‘MThd’; <length> is a 32-bit representation of the number 6 (high byte first).

The data section contains three 16-bit words, stored most-significant byte first.

The first word, <format>, specifies the overall organisation of the file. Only three values of <format> are specified:

Format	Description
0	the file contains a single multi-channel track
1	the file contains one or more simultaneous tracks (or MIDI outputs) of a sequence
2	the file contains one or more sequentially independent single-track patterns

More information about these formats is provided below.

The next word, <ntrks>, is the number of track chunks in the file. It will always be 1 for a format 0 file.

The third word, <division>, specifies the meaning of the delta-times. It has two formats, one for metrical time, and one for time-code-based time:

bit 15	bits 14 thru 8	bits 7 thru 0
0	ticks per quarter-note
1	negative SMPTE format	ticks per frame

If bit 15 of <division> is zero, the bits 14 thru 0 represent the number of delta time “ticks” which make up a quarter-note. For instance, if division is 96, then a time interval of an eighth-note between two events in the file would be 48.

If bit 15 of <division> is a one, delta times in a file correspond to subdivisions of a second, in a way consistent with SMPTE² and MIDI Time Code. Bits 14 thru 8 contain one of the four values -24, -25, -29, or -30, corresponding to the four standard SMPTE and MIDI Time Code formats (-29 corresponds to 30 drop frame), and represents the number of frames per second. These negative numbers are stored in two’s compliment form. The second byte (stored positive) is the resolution within a frame: typical values may be 4 (MIDI Time Code resolution), 8, 10, 80 (bit resolution), or 100. This stream allows exact specifications of time-code-based tracks, but also allows millisecond-based tracks by specifying 25 frames/sec and a resolution of 40 units per frame. If the events in a file are stored with a bit resolution of thirty-frame time code, the division word would be E250 hex.

MIDI File Formats 0, 1 and 2

A Format 0 file has a header chunk followed by one track chunk. It is the most interchangeable representation of data. It is very useful for a simple single-track player in a program which needs to make synthesisers make sounds, but which is primarily concerned with something else such as mixers or sound effect boxes. It is very desirable to be able to produce such a format, even if your program is track-based, in order to work with these simple programs.

A Format 1 or 2 file has a header chunk followed by one or more track chunks. programs which support several simultaneous tracks should be able to save and read data in format 1, a vertically one dimensional form, that is, as a collection of tracks. Programs which support several independent patterns should be able to save and read data in format 2, a horizontally one dimensional form. Providing these minimum capabilities will ensure maximum interchangeability.

In a MIDI system with a computer and a SMPTE synchroniser which uses Song Pointer and Timing Clock, tempo maps (which describe the tempo throughout the track, and may also include time signature information, so that the bar number may be derived) are generally created on the computer. To use them with the synchroniser, it is necessary to transfer them from the computer. To make it easy for the synchroniser to extract this data from a MIDI File, tempo information should always be stored in the first MTrk chunk. For a format 0 file, the tempo will be scattered through the track and the tempo map reader should ignore the intervening events; for a format 1 file, the tempo map must be stored as the first track. It is polite to a tempo map reader to offer your user the ability to make a format 0 file with just the tempo, unless you can use format 1.

All MIDI Files should specify tempo and time signature. If they don’t, the time signature is assumed to be $\frac{4}{4}$, and the tempo 120 beats per minute. In format 0, these meta-events should occur at least at the beginning of the single multi-channel track. In format 1, these meta-events should be contained in the first track. In format 2, each of the temporally independent patterns should contain at least initial time signature and tempo information.

Format IDs to support other structures may be defined in the future. A program encountering an unknown format ID may still read other MTrk chunks it finds from the file, as format 1 or 2, if its user can make sense of them and arrange them into some other structure if appropriate. Also, more parameters may be added to the MThd chunk in the future: it is important to read and honour the length, even if it is longer than 6.

Track Chunks

The track chunks (type MTrk) are where actual song data is stored. Each track chunk is simply a stream of MIDI events (and non-MIDI events), preceded by delta-time values. The format for Track Chunks (described below) is exactly the same for all three formats (0, 1, and 2: see “[Header Chunk][Header Chunks]” above) of MIDI Files.

MTrk chunk

Here is the syntax of an MTrk chunk (the + means “one or more”: at least one MTrk event must be present):

<Track Chunk> = <chunk type><length><MTrk event>+

The syntax of an MTrk event is very simple:

<MTrk event> = <delta-time><event>

delta-time

<delta-time> is stored as a variable-length quantity. It represents the amount of time before the following event. If the first event in a track occurs at the very beginning of a track, or if two events occur simultaneously, a delta-time of zero is used. Delta-times are always present. (Not storing delta-times of 0 requires at least two bytes for any other value, and most delta-times aren’t zero.) Delta-time is in some fraction of a beat (or a second, for recording a track with SMPTE times), as specified in the header chunk.

<event> = <MIDI event> | <sysex event> | <meta-event>

MIDI event

<MIDI event> is any MIDI channel message See Appendix 1 - [MIDI Messages]. Running status is used: status bytes of MIDI channel messages may be omitted if the preceding event is a MIDI channel message with the same status. The first event in each MTrk chunk must specify status. Delta-time is not considered an event itself: it is an integral part of the syntax for an MTrk event. Notice that running status occurs across delta-times.

sysex event

<sysex event> is used to specify a MIDI system exclusive message, either as one unit or in packets, or as an “escape” to specify any arbitrary bytes to be transmitted. See Appendix 1 - [MIDI Messages]. A normal complete system exclusive message is stored in a MIDI File in this way:

F0 <length> <bytes to be transmitted after F0>

The length is stored as a variable-length quantity. It specifies the number of bytes which follow it, not including the F0 or the length itself. For instance, the transmitted message F0 43 12 00 07 F7 would be stored in a MIDI File as F0 05 43 12 00 07 F7. It is required to include the F7 at the end so that the reader of the MIDI File knows that it has read the entire message.

Another form of sysex event is provided which does not imply that an F0 should be transmitted. This may be used as an “escape” to provide for the transmission of things which would not otherwise be legal, including system realtime messages, song pointer or select, MIDI Time Code, etc. This uses the F7 code:

F7 <length> <all bytes to be transmitted>

Unfortunately, some synthesiser manufacturers specify that their system exclusive messages are to be transmitted as little packets. Each packet is only part of an entire syntactical system exclusive message, but the times they are transmitted are important. Examples of this are the bytes sent in a CZ patch dump, or the FB-01’s “system exclusive mode” in which microtonal data can be transmitted. The F0 and F7 sysex events may be used together to break up syntactically complete system exclusive messages into timed packets.

An F0 sysex event is used for the first packet in a series – it is a message in which the F0 should be transmitted. An F7 sysex event is used for the remainder of the packets, which do not begin with F0. (Of course, the F7 is not considered part of the system exclusive message).

A syntactic system exclusive message must always end with an F7, even if the real-life device didn’t send one, so that you know when you’ve reached the end of an entire sysex message without looking ahead to the next event in the MIDI File. If it’s stored in one complete F0 sysex event, the last byte must be an F7. There also must not be any transmittable MIDI events in between the packets of a multi-packet system exclusive message. This principle is illustrated in the paragraph below.

Here is a MIDI File of a multi-packet system exclusive message: suppose the bytes F0 43 12 00 were to be sent, followed by a 200-tick delay, followed by the bytes 43 12 00 43 12 00, followed by a 100-tick delay, followed by the bytes 43 12 00 F7, this would be in the MIDI File:

hex	value
F0 03 43 12 00
81 48	200-tick delta time
F7 06 43 12 00 43 12 00
64	100-tick delta time
F7 04 43 12 00 F7

When reading a MIDI File, and an F7 sysex event is encountered without a preceding F0 sysex event to start a multi-packet system exclusive message sequence, it should be presumed that the F7 event is being used as an “escape”. In this case, it is not necessary that it end with an F7, unless it is desired that the F7 be transmitted.

meta-event

<meta-event> specifies non-MIDI information useful to this format or to sequencers, with this syntax:

FF <type> <length> <bytes>

All meta-events begin with FF, then have an event type byte (which is always less than 128), and then have the length of the data stored as a variable-length quantity, and then the data itself. If there is no data, the length is 0. As with chunks, future meta-events may be designed which may not be known to existing programs, so programs must properly ignore meta-events which they do not recognise, and indeed should expect to see them. Programs must never ignore the length of a meta-event which they do not recognise, and they shouldn’t be surprised if it’s bigger than expected. If so, they must ignore everything past what they know about. However, they must not add anything of their own to the end of the meta-event. Sysex events and meta events cancel any running status which was in effect. Running status does not apply to and may not be used for these messages.

Meta-Events

A few meta-events are defined herein. It is not required for every program to support every meta-event.

In the syntax descriptions for each of the meta-events a set of conventions is used to describe parameters of the events. The FF which begins each event, the type of each event, and the lengths of events which do not have a variable amount of data are given directly in hexadecimal. A notation such as dd or se, which consists of two lower-case letters, mnemonically represents an 8-bit value. Four identical lower-case letters such as wwww mnemonically refer to a 16-bit value, stored most-significant-byte first. Six identical lower-case letters such as tttttt refer to a 24-bit value, stored most-significant-byte first. The notation len refers to the length portion of the meta-event syntax, that is, a number, stored as a variable- length quantity, which specifies how many bytes (possibly text) data were just specified by the length.

In general, meta-events in a track which occur at the same time may occur in any order. If a copyright event is used, it should be placed as early as possible in the file, so it will be noticed easily. Sequence Number and Sequence/Track Name events, if present, must appear at time 0. An end-of-track event must occur as the last event in the track.

Meta-Event Definitions

FF 00 02 Sequence Number

This optional event, which must occur at the beginning of a track, before any nonzero delta-times, and before any transmittable MIDI events, specifies the number of a sequence. In a format 2 MIDI File, it is used to identify each “pattern” so that a “song” sequence using the Cue message can refer to the patterns. If the ID numbers are omitted, the sequences’ locations in order in the file are used as defaults. In a format 0 or 1 MIDI File, which only contain one sequence, this number should be contained in the first (or only) track. If transfer of several multitrack sequences is required, this must be done as a group of format 1 files, each with a different sequence number.

FF 01 len text Text Event

Any amount of text describing anything. It is a good idea to put a text event right at the beginning of a track, with the name of the track, a description of its intended orchestration, and any other information which the user wants to put there. Text events may also occur at other times in a track, to be used as lyrics, or descriptions of cue points. The text in this event should be printable ASCII characters for maximum interchange. However, other character codes using the high-order bit may be used for interchange of files between different programs on the same computer which supports an extended character set. Programs on a computer which does not support non-ASCII characters should ignore those characters.

Meta-event types 01 through 0F are reserved for various types of text events, each of which meets the specification of text events (above) but is used for a different purpose:

FF 02 len text Copyright Notice

Contains a copyright notice as printable ASCII text. The notice should contain the characters (C), the year of the copyright, and the owner of the copyright. If several pieces of music are in the same MIDI File, all of the copyright notices should be placed together in this event so that it will be at the beginning of the file. This event should be the first event in the track chunk, at time 0.

FF 03 len text Sequence/Track Name

If in a format 0 track, or the first track in a format 1 file, the name of the sequence. Otherwise, the name of the track.

FF 04 len text Instrument Name

A description of the type of instrumentation to be used in that track. May be used with the MIDI Prefix meta-event to specify which MIDI channel the description applies to, or the channel may be specified as text in the event itself.

FF 05 len text Lyric

A lyric to be sung. Generally, each syllable will be a separate lyric event which begins at the event’s time.

FF 06 len text Marker

Normally in a format 0 track, or the first track in a format 1 file. The name of that point in the sequence, such as a rehearsal letter or section name (“First Verse”, etc.)

FF 07 len text Cue Point

A description of something happening on a film or video screen or stage at that point in the musical score (“Car crashes into house”, “curtain opens”, “she slaps his face”, etc.)

FF 20 01 cc MIDI Channel Prefix

The MIDI channel (0-15) contained in this event may be used to associate a MIDI channel with all events which follow, including System exclusive and meta-events. This channel is “effective” until the next normal MIDI event (which contains a channel) or the next MIDI Channel Prefix meta-event. If MIDI channels refer to “tracks”, this message may be put into a format 0 file, keeping their non-MIDI data associated with a track. This capability is also present in Yamaha’s ESEQ file format.

FF 2F 00 End of Track

This event is not optional. It is included so that an exact ending point may be specified for the track, so that an exact length is defined, which is necessary for tracks which are looped or concatenated.

FF 51 03 tttttt Set Tempo (in microseconds per MIDI quarter-note)

This event indicates a tempo change. Another way of putting “microseconds per quarter-note” is “24^ths^ of a microsecond per MIDI clock”. Representing tempos as time per beat instead of beat per time allows absolutely exact long-term synchronisation with a time-based sync protocol such as SMPTE time code or MIDI time code. The amount of accuracy provided by this tempo resolution allows a four-minute piece at 120 beats per minute to be accurate within 500 usec³ at the end of the piece. Ideally, these events should only occur where MIDI clocks would be located – this convention is intended to guarantee, or at least increase the likelihood, of compatibility with other synchronisation devices so that a time signature/tempo map stored in this format may easily be transferred to another device.

FF 54 05 hr mn se fr ff SMPTE Offset

This event, if present, designates the SMPTE time at which the track chunk is supposed to start. It should be present at the beginning of the track, that is, before any nonzero delta-times, and before any transmittable MIDI events. the hour must be encoded with the SMPTE format, just as it is in MIDI Time Code. In a format 1 file, the SMPTE Offset must be stored with the tempo map, and has no meaning in any of the other tracks. The ff field contains fractional frames, in 100ths of a frame, even in SMPTE-based tracks which specify a different frame subdivision for delta-times.

FF 58 04 nn dd cc bb Time Signature

The time signature is expressed as four numbers. nn and dd represent the numerator and denominator of the time signature as it would be notated. The denominator is a negative power of two: 2 represents a quarter-note, 3 represents an eighth-note, etc. The cc parameter expresses the number of MIDI clocks in a metronome click. The bb parameter expresses the number of notated 32nd-notes in a MIDI quarter-note (24 MIDI clocks). This was added because there are already multiple programs which allow a user to specify that what MIDI thinks of as a quarter-note (24 clocks) is to be notated as, or related to in terms of, something else.

Therefore, the complete event for $\frac{6}{8}$ time, where the metronome clicks every three eighth-notes, but there are 24 clocks per quarter-note, 72 to the bar, would be (in hex):

FF 58 04 06 03 24 08

That is, $\frac{6}{8}$ time (8 is 2 to the 3rd power, so this is 06 03), 36 MIDI clocks per dotted-quarter (24 hex!), and eight notated 32nd-notes per quarter-note.

FF 59 02 sf mi Key Signature

sf = -7: 7 flats
sf = -1: 1 flat
sf = 0: key of C
sf = 1: 1 sharp
sf = 7: 7 sharps

mi = 0: major key
mi = 1: minor key

FF 7F len data Sequencer Specific Meta-Event

Special requirements for particular sequencers may use this event type: the first byte or bytes of data is a manufacturer ID (these are one byte, or if the first byte is 00, three bytes). As with MIDI System Exclusive, manufacturers who define something using this meta-event should publish it so that others may be used by a sequencer which elects to use this as its only file format; sequencers with their established feature-specific formats should probably stick to the standard features when using this format.

See Appendix 2 - [Program Fragments and Example MIDI Files]

Appendix

MIDI Messages

A MIDI message is made up of an eight-bit status byte which is generally followed by one or two data bytes. There are a number of different types of MIDI messages. At the highest level, MIDI messages are classified as being either Channel Messages or System Messages. Channel messages are those which apply to a specific Channel, and the Channel number is included in the status byte for these messages. System messages are not Channel specific, and no Channel number is indicated in their status bytes.

Channel Messages may be further classified as being either Channel Voice Messages, or Mode Messages. Channel Voice Messages carry musical performance data, and these messages comprise most of the traffic in a typical MIDI data stream. Channel Mode messages affect the way a receiving instrument will respond to the Channel Voice messages.

MIDI System Messages are classified as being System Common Messages, System Real Time Messages, or System Exclusive Messages. System Common messages are intended for all receivers in the system. System Real Time messages are used for synchronisation between clock-based MIDI components. System Exclusive messages include a Manufacturer’s Identification (ID) code, and are used to transfer any number of data bytes in a format specified by the referenced manufacturer.

Table of Major MIDI Messages

Channel Voice Messages

bin stat	data D7-D0 stat	hex	Description
1000nnnn	0kkkkkkk 0vvvvvvv	0x8n	Note Off event. This message is sent when a note is released (ended). kkkkkkk is the key (note) number. vvvvvvv is the velocity.
1001nnnn	0kkkkkkk 0vvvvvvv	0x9n	Note On event. This message is sent when a note is depressed (start). kkkkkkk is the key (note) number. vvvvvvv is the velocity.
1010nnnn	0kkkkkkk 0vvvvvvv	0xAn	Polyphonic Key Pressure (Aftertouch). This message is sent when a note is depressed (start). kkkkkkk is the key (note) number. vvvvvvv is the velocity.
1011nnnn	0kkkkkkk 0vvvvvvv	0xBn	Control Change. This message is sent when a controller value changes. Controllers include devices such as pedals and levers. Certain controller numbers are reserved for specific purposes. See [Channel Mode Messages]. ccccccc is the controller number. vvvvvvv is the new value.
1100nnnn	0ppppppp	0xCn	Program Change. This message sent when the patch number changes. ppppppp is the new program number.
1101nnnn	0vvvvvvv	0xDn	Channel Pressure (After-touch). This message is most often sent by pressing down on the key after it “bottoms out”. This message is different from polyphonic after-touch. Use this message to send the single greatest pressure value (of all the current depressed keys). vvvvvvv is the pressure value.
1110nnnn	0lllllll	0xEn	Pitch Wheel Change. 0mmmmmmm This message is sent to indicate a change in the pitch wheel. The pitch wheel is measured by a fourteen bit value. Centre (no pitch change) is 2000H. Sensitivity is a function of the transmitter. lllllll are the least significant 7 bits. mmmmmmm are the most significant 7 bits.

Table: Channel Voice Messages

Channel Mode Messages

(See also Control Change, above)

byte status	data bytes 7-0	Description
1011nnnn	0ccccccc	Channel Mode Messages. 0vvvvvvv This the same code as the Control Change (above), but implements Mode control by using reserved controller numbers. The numbers are: Local Control. When Local Control is Off, all devices on a given channel will respond only to data received over MIDI. Played data, etc. will be ignored. Local Control On restores the functions of the normal controllers. c = 122, v = 0: Local Control Off c = 122, v = 127: Local Control On All Notes Off. When an All Notes Off is received all oscillators will turn off. c = 123, v = 0: All Notes Off c = 124, v = 0: Omni Mode Off c = 125, v = 0: Omni Mode On c = 126, v = M: Mono Mode On (Poly Off) where M is the number of channels (Omni Off) or 0 (Omni On) c = 127, v = 0: Poly Mode On (Mono Off) (Note: These four messages also cause All Notes Off)

Table: Channel Mode Messages

System Common Messages

byte status	data bytes	D7-D0	hex status	Description
11110000	0iiiiiii	.. .. 0ddddddd 11110111	0xF0	System Exclusive. 0ddddddd This message makes up for all that MIDI doesn’t support. iiiiiii is usually a seven-bit Manufacturer’s I.D. code. If the synthesiser recognises the I.D. code as its own, it will listen to the rest of the message ddddddd. Otherwise, the message will be ignored. System Exclusive is used to send bulk dumps such as patch parameters and other non-spec data. (Note: Real-Time messages ONLY may be interleaved with a System Exclusive.) This message also is used for extensions called Universal Exclusive Messages.
11110001			0xF1	Undefined.
11110010	0lllllll	0mmmmmmm	0xF2	Song Position Pointer. This is an internal 14 bit register that holds the number of MIDI beats (1 beat=six MIDI clocks) since the start of the song. l is the LSB, m the MSB.
11110011	0sssssss		0xF3	Song Select. The Song Select specifies which sequence or song is to be played.
11110100			0xF4	Undefined.
11110101			0xF5	Undefined.
11110110			0xF6	Tune Request. Upon receiving a Tune Request, all analog synthesisers should tune their oscillators.
11110111			0xF7	End of Exclusive. Used to terminate a System Exclusive dump (see above).

Table: System Common Messages

System Realtime Messages

byte status	data bytes D7-D0	hex status	Description
11111000		0xF8	Timing Clock. Sent 24 times per quarter note when synchronisation is required.
11111001		0xF9	Undefined.
11111010		0xFA	Start. Start the current sequence playing. (This message will be followed with Timing Clocks).
11111011		0xFB	Continue. Continue at the point the sequence was Stopped.
11111100		0xFC	Stop. Stop the current sequence.
11111101		0xFD	Undefined.
11111110		0xFE	Active Sensing. Use of this message is optional. When initially sent, the receiver will expect to receive another Active Sensing message each 300ms (max), or it will be assume that the connection has been terminated. At termination, the receiver will turn off all voices and return to normal (non-active sensing) operation.
11111111		0xFF	Reset Reset all receivers in the system to power-up status. This should be used sparingly, preferably under manual control. In particular, it should not be sent on power-up. In a MIDI file this is used as an escape to introduce <meta events>.

Table: System Realtime Messages

Table of MIDI Controller Messages

[2nd byte {bin,hex,dec}, function, 3rd byte {Value,Use}]

bin	hex	dec	Function	Value	Use
00000000	00	0	Bank Select (MSB:0, LSB:32) GM2	0-127	MSB
00000001	01	1	* Modulation wheel (Depth) GM2	0-127	MSB
00000010	02	2	Breath control	0-127	MSB
00000011	03	3	Undefined	0-127	MSB
00000100	04	4	Foot controller	0-127	MSB
00000101	05	5	Portamento time GM2	0-127	MSB
00000110	06	6	Data Entry GM2	0-127	MSB
00000111	07	7	* Channel Volume (GM1 Main Volume) GM2	0-127	MSB
00001000	08	8	Balance	0-127	MSB
00001001	09	9	Undefined	0-127	MSB
00001010	0A	10	* Pan GM2	0-127	MSB
00001011	0B	11	* Expression Controller GM2	0-127	MSB
00001100	0C	12	Effect control 1	0-127	MSB
00001101	0D	13	Effect control 2	0-127	MSB
00001110	0E	14	Undefined	0-127	MSB
00001111	0F	15	Undefined	0-127	MSB
00010000	10	16	General Purpose Controller #1	0-127	MSB
00010001	11	17	General Purpose Controller #2	0-127	MSB
00010010	12	18	General Purpose Controller #3	0-127	MSB
00010011	13	19	General Purpose Controller #4	0-127	MSB
00010100	14	20	Undefined	0-127	MSB
00010101	15	21	Undefined	0-127	MSB
00010110	16	22	Undefined	0-127	MSB
00010111	17	23	Undefined	0-127	MSB
00011000	18	24	Undefined	0-127	MSB
00011001	19	25	Undefined	0-127	MSB
00011010	1A	26	Undefined	0-127	MSB
00011011	1B	27	Undefined	0-127	MSB
00011100	1C	28	Undefined	0-127	MSB
00011101	1D	29	Undefined	0-127	MSB
00011110	1E	30	Undefined	0-127	MSB
00011111	1F	31	Undefined	0-127	MSB
00100000	20	32	Bank Select	0-127	LSB
00100001	21	33	Modulation wheel	0-127	LSB
00100010	22	34	Breath control	0-127	LSB
00100011	23	35	Undefined	0-127	LSB
00100100	24	36	Foot controller	0-127	LSB
00100101	25	37	Portamento time	0-127	LSB
00100110	26	38	Data entry GM2	0-127	LSB
00100111	27	39	Channel Volume (formerly Main Volume)	0-127	LSB
00101000	28	40	Balance	0-127	LSB
00101001	29	41	Undefined	0-127	LSB
00101010	2A	42	Pan	0-127	LSB
00101011	2B	43	Expression Controller	0-127	LSB
00101100	2C	44	Effect control 1	0-127	LSB
00101101	2D	45	Effect control 2	0-127	LSB
00101110	2E	46	Undefined	0-127	LSB
00101111	2F	47	Undefined	0-127	LSB
00110000	30	48	General Purpose Controller #1	0-127	LSB
00110001	31	49	General Purpose Controller #2	0-127	LSB
00110010	32	50	General Purpose Controller #3	0-127	LSB
00110011	33	51	General Purpose Controller #4	0-127	LSB
00110100	34	52	Undefined	0-127	LSB
00110101	35	53	Undefined	0-127	LSB
00110110	36	54	Undefined	0-127	LSB
00110111	37	55	Undefined	0-127	LSB
00111000	38	56	Undefined	0-127	LSB
00111001	39	57	Undefined	0-127	LSB
00111010	3A	58	Undefined	0-127	LSB
00111011	3B	59	Undefined	0-127	LSB
00111100	3C	60	Undefined	0-127	LSB
00111101	3D	61	Undefined	0-127	LSB
00111110	3E	62	Undefined	0-127	LSB
00111111	3F	63	Undefined	0-127	LSB
01000000	40	64	* Damper pedal on/off (Sustain) GM2	<63=off\	>64=on
01000001	41	65	Portamento on/off GM2	<63=off\	>64=on
01000010	42	66	Sustenuto on/off GM2	<63=off\	>64=on
01000011	43	67	Soft pedal on/off GM2	<63=off\	>64=on
01000100	44	68	Legato Footswitch	<63=off\	>64=on
01000101	45	69	Hold 2	<63=off\	>64=on
01000110	46	70	Sound Controller 1 (Sound Variation)	0-127	LSB
01000111	47	71	Sound Controller 2 (Timbre GM2 Resonance)	0-127	LSB
01001000	48	72	Sound Controller 3 (GM2 Release Time)	0-127	LSB
01001001	49	73	Sound Controller 4 (GM2 Attack Time)	0-127	LSB
01001010	4A	74	Sound Controller 5 (GM2 Brightness)	0-127	LSB
01001011	4B	75	Sound Controller 6 (GM2 Decay)	0-127	LSB
01001100	4C	76	Sound Controller 7 (GM2 Vibrato Rate)	0-127	LSB
01001101	4D	77	Sound Controller 8 (GM2 Vibrato Depth)	0-127	LSB
01001110	4E	78	Sound Controller 9 (GM2 Vibrato Delay)	0-127	LSB
01001111	4F	79	Sound Controller 10	0-127	LSB
01010000	50	80	General Purpose Controller #5	0-127	LSB
01010001	51	81	General Purpose Controller #6	0-127	LSB
01010010	52	82	General Purpose Controller #7	0-127	LSB
01010011	53	83	General Purpose Controller #8	0-127	LSB
01010100	54	84	Portamento Control	0-127	Source Note
01010101	55	85	Undefined	0-127	LSB
01010110	56	86	Undefined	0-127	LSB
01010111	57	87	Undefined	0-127	LSB
01011000	58	88	Undefined	0-127	LSB
01011001	59	89	Undefined	0-127	LSB
01011010	5A	90	Undefined	0-127	LSB
01011011	5B	91	Effects 1 Depth (GM2 Reverb Send Level)	0-127	LSB
01011100	5C	92	Effects 2 Depth	0-127	LSB
01011101	5D	93	Effects 3 Depth (GM2 Chorus Send Level)	0-127	LSB
01011110	5E	94	Effects 4 Depth	0-127	LSB
01011111	5F	95	Effects 5 Depth	0-127	LSB
01100000	60	96	Data entry	+1	N/A
01100001	61	97	Data entry	-1	N/A
01100010	62	98	Non-Registered Parameter Number LSB	0-127	LSB
01100011	63	99	Non-Registered Parameter Number MSB	0-127	MSB
01100100	64	100	* Registered Parameter Number LSB GM2	0-127	LSB
01100101	65	101	* Registered Parameter Number MSB	0-127	MSB
01100111	67	103	Undefined	?
01101000	68	104	Undefined	?
01101001	69	105	Undefined	?
01101010	6A	106	Undefined	?
01101011	6B	107	Undefined	?
01101100	6C	108	Undefined	?
01101101	6D	109	Undefined	?
01101110	6E	110	Undefined	?
01101111	6F	111	Undefined	?
01110000	70	112	Undefined	?
01110001	71	113	Undefined	?
01110010	72	114	Undefined	?
01110011	73	115	Undefined	?
01110100	74	116	Undefined	?
01110101	75	117	Undefined	?
01110110	76	118	Undefined	?
01110111	77	119	Undefined	?
01111000	78	120	All Sound Off	0
01111001	79	121	* Reset All Controllers	0
01111010	7A	122	Local control on/off	0=off 127=on
01111011	7B	123	* All notes off	0
01111100	7C	124	Omni mode off (+ all notes off)	0
01111101	7D	125	Omni mode on (+ all notes off)	0
01111110	7E	126	Poly mode on/off (+ all notes off)	//
01111111	7F	127	Poly mode on (incl mono=off +all notes off)	0

Table| Table of MIDI Controller Messages

* Equipment must respond in order to comply with General MIDI level 1.
** This equals the number of channels, or zero if the number of channels equals the number of voices in the

Table of MIDI Note Numbers

This table lists all MIDI Note Numbers by octave.

The absolute octave number designations are based on Middle C = C4, which is an arbitrary but widely used assignment.

Octave	C	C	D	D#	E	F	F#	G	G#	A	A#	B
-1	0	1	2	3	4	5	6	7	8	9	10	11
0	12	13	14	15	16	17	18	19	20	21	22	23
1	24	25	26	27	28	29	30	31	32	33	34	35
2	36	37	38	39	40	41	42	43	44	45	46	47
3	48	49	50	51	52	53	54	55	56	57	58	59
4	60	61	62	63	64	65	66	67	68	69	70	71
5	72	73	74	75	76	77	78	79	80	81	82	83
6	84	85	86	87	88	89	90	91	92	93	94	95
7	96	97	98	99	100	101	102	103	104	105	106	107
8	108	109	110	111	112	113	114	115	116	117	118	119
9	120	121	122	123	124	125	126	127

Table: MIDI Note Numbers

General MIDI Instrument Patch Map

• These sounds are the same for all MIDI Channels except Channel 10, which has only percussion sounds and some sound “effects”. (See Appendix 1.5 - [General MIDI Percussion Key Map])
• The names of the instruments indicate what sort of sound will be heard when that instrument number (MIDI Program Change or “PC#”) is selected on the GM synthesizer.

GM Instrument Families

The General MIDI instrument sounds are grouped by families. In each family are 8 specific instruments.

PC#	Family	PC#	Family
1-8	Piano	65-72	Reed
9-16	Chromatic Percussion	73-80	Pipe
17-24	Organ	81-88	Synth Lead
25-32	Guitar	89-96	Synth Pad
33-40	Bass	97-104	Synth Effects
41-48	Strings	95-112	Ethnic
49-56	Ensemble	113-120	Percussive
57-64	Brass	120-128	Sound Effects

Table: GM Instrument Families

GM Instrument Patch Map

Note: While GM does not define the actual characteristics of any sounds, the names in parentheses after each of the synth leads, pads, and sound effects are, in particular, intended only as guides.

Also Note: Numbers as defined here are -= 1 in their binary form (one less than the value shown in the table).

 1.  Acoustic Grand Piano                65. Soprano Sax
 2.  Bright Acoustic Piano               66. Alto Sax
 3.  Electric Grand Piano                67. Tenor Sax
 4.  Honky-tonk Piano                    68. Baritone Sax
 5.  Electric Piano 1 (Rhodes Piano)     69. Oboe
 6.  Electric Piano 2 (Chorused Piano)   70. English Horn
 7.  Harpsichord                         71. Bassoon
 8.  Clavinet                            72. Clarinet
 9.  Celesta                             73. Piccolo
10. Glockenspiel                         74. Flute
11. Music Box                            75. Recorder
12. Vibraphone                           76. Pan Flute
13. Marimba                              77. Blown Bottle
14. Xylophone                            78. Shakuhachi
15. Tubular Bells                        79. Whistle
16. Dulcimer (Santur)                    80. Ocarina
17. Drawbar Organ (Hammond)              81. Lead 1 (square wave)
18. Percussive Organ                     82. Lead 2 (sawtooth wave)
19. Rock Organ                           83. Lead 3 (calliope)
20. Church Organ                         84. Lead 4 (chiffer)
21. Reed Organ                           85. Lead 5 (charang)
22. Accordion (French)                   86. Lead 6 (voice solo)
23. Harmonica                            87. Lead 7 (fifths)
24. Tango Accordion (Band neon)          88. Lead 8 (bass + lead)
25. Acoustic Guitar (nylon)              89. Pad 1 (new age Fantasia)
26. Acoustic Guitar (steel)              90. Pad 2 (warm)
27. Electric Guitar (jazz)               91. Pad 3 (polysynth)
28. Electric Guitar (clean)              92. Pad 4 (choir space voice)
29. Electric Guitar (muted)              93. Pad 5 (bowed glass)
30. Overdriven Guitar                    94. Pad 6 (metallic pro)
31. Distortion Guitar                    95. Pad 7 (halo)
32. Guitar harmonics                     96. Pad 8 (sweep)
33. Acoustic Bass                        97. FX 1 (rain)
34. Electric Bass (fingered)             98. FX 2 (soundtrack)
35. Electric Bass (picked)               99. FX 3 (crystal)
36. Fretless Bass                       100. FX4 (atmosphere)
37. Slap Bass 1                         101. FX 5 (brightness)
38. Slap Bass 2                         102. FX 6 (goblins)
39. Synth Bass 1                        103. FX 7 (echoes, drops)
40. Synth Bass 2                        104. FX 8 (sci-fi, star theme)
41. Violin                              105. Sitar
42. Viola                               106. Banjo
43. Cello                               107. Shamisen
44. Contrabass                          108. Koto
45. Tremolo Strings                     109. Kalimba
46. Pizzicato Strings                   110. Bag pipe
47. Orchestral Harp                     111. Fiddle
48. Timpani                             112. Shanai
49. String Ensemble 1 (strings)         113. Tinkle Bell
50. String Ensemble 2 (slow strings)    114. Agogo
51. SynthStrings 1                      115. Steel Drums
52. SynthStrings 2                      116. Woodblock
53. Choir Aahs                          117. Taiko Drum
54. Voice Oohs                          118. Melodic Tom
55. Synth Voice                         119. Synth Drum
56. Orchestra Hit                       120. Reverse Cymbal
57. Trumpet                             121. Guitar Fret Noise
58. Trombone                            122. Breath Noise
59. Tuba                                123. Seashore
60. Muted Trumpet                       124. Bird Tweet
61. French Horn                         125. Telephone Ring
62. Brass Section                       126. Helicopter
63. SynthBrass 1                        127. Applause
64. SynthBrass 2                        128. Gunshot

General MIDI Percussion Key Map

35 B1  Acoustic Bass Drum   59 B3  Ride Cymbal 2
36 C2  Bass Drum 1          60 C4  Hi Bongo
37 C#2 Side Stick           61 C#4 Low Bongo
38 D2  Acoustic Snare       62 D4  Mute Hi Conga
39 D#2 Hand Clap            63 D#4 Open Hi Conga
40 E2  Electric Snare       64 E4  Low Conga
41 F2  Low Floor Tom        65 F4  High Timbale
42 F#2 Closed Hi Hat        66 F#4 Low Timbale
43 G2  High Floor Tom       67 G4  High Agogo
44 G#2 Pedal Hi-Hat         68 G#4 Low Agogo
45 A2  Low Tom              69 A4  Cabasa
46 A#2 Open Hi-Hat          70 A#4 Maracas
47 B2  Low-Mid Tom          71 B4  Short Whistle
48 C3  Hi Mid Tom           72 C5  Long Whistle
49 C#3 Crash Cymbal 1       73 C#5 Short Guiro
50 D3  High Tom             74 D5  Long Guiro
51 D#3 Ride Cymbal 1        75 D#5 Claves
52 E3  Chinese Cymbal       76 E5  Hi Wood Block
53 F3  Ride Bell            77 F5  Low Wood Block
54 F#3 Tambourine           78 F#5 Mute Cuica
55 G3  Splash Cymbal        79 G5  Open Cuica
56 G#3 Cowbell              80 G#5 Mute Triangle
57 A3  Crash Cymbal 2       81 A5  Open Triangle
58 A#3 Vibraslap

GS/GM2 Note (as in the chart above)
These are the same patch numbers as defined in the original version of GS. Drum bank is accessed by setting cc#0 (Bank Select MSB) to 120 and cc#32 (Bank Select LSB) to 0 and PC (Program Change) to select drum kit.

Program Fragments and Example MIDI Files

Here are some of the routines to read and write variable-length numbers in MIDI Files. These routines are in C, and use getc and putc, which read and write single 8-bit characters from/to the files infile and outfile.

WriteVarLen(value) register long value;
{
  register long buffer;
  buffer = value & 0x7f;
  while((value >>= 7) > 0)
  {
    buffer <<= 8;
    buffer |= 0x80;
    buffer += (value &0x7f);
  }
  while (TRUE)
  {
    putc(buffer,outfile);
    if(buffer & 0x80) buffer >>= 8;
    else
    break;
  }
}
doubleword ReadVarLen()
{
  register doubleword value;
  register byte c;
  if((value = getc(infile)) & 0x80)
  {
    value &= 0x7f;
    do
    {
      value = (value << 7) + ((c = getc(infile))) & 0x7f);
    } while (c & 0x80);
  }
  return(value);
}

As an example, MIDI Files for the following excerpt are shown below. First, a format 0 file is shown, with all information intermingled; then, a format 1 file is shown with all data separated into four tracks: one for tempo and time signature, and three for the notes. A resolution of 96 “ticks” per quarter note is used. A time signature of $\frac{4}{4}$ and a tempo of 120, though implied, are explicitly stated.

The contents of the MIDI stream represented by this example are broken down here:

Delta Time (decimal)	Event-Code (hex)	Other bytes (decimal)	Comment
0	FF 58	04 04 02 24 08	4 bytes; $\frac{4}{4}$ time; 24 MIDI clocks/click, 8 32nd notes/ 24 MIDI clocks (24 MIDI clocks = 1 crotchet = 1 beat)
0	FF 51	03 500000	3 bytes: 500,000 usec / quarter note = 120 beats/minute
0	C0	5	Ch.1 Program Change 5 = GM Patch 6 = Electric Piano 2
0	C1	46	Ch.2 Program Change 46 = GM Patch 47 = Harp
0	C2	70	Ch.3 Program Change 70 = GM Patch 71 = Bassoon
0	92	48 96	Ch.3 Note On C3, forte
0	92	60 96	Ch.3 Note On C4, forte
96	91	67 64	Ch.2 Note On G4, mezzo-forte
96	90	76 32	Ch.1 Note On E5, piano
192	82	48 64	Ch.3 Note Off C3, standard
0	82	60 64	Ch.3 Note Off C4, standard
0	81	67 64	Ch.2 Note Off G4, standard
0	80	76 64	Ch.1 Note Off E5, standard
0	FF 2F	00	Track End

The entire format 0 MIDI file contents in hex follow. First, the header chunk:

4D 54 68 64 MThd
00 00 00 06 chunk length
00 00       format 0
00 01       one track
00 60       96 per quarter-note

Then the track chunk. Its header followed by the events (notice the running status is used in places):

Delta-Time	Event	Comments
00	FF 58 04 04 02 18 08	time signature
00	FF 51 03 07 A1 20	tempo
00	C0 05
00	C1 2E
00	C2 46
00	92 30 60
00	3C 60	running status
60	91 43 40
60	90 4C 20
81 40	82 30 40	two-byte delta-time
00	3C 40	running status
00	81 43 40
00	80 4C 40
00	FF 2F 00	end of track

A format 1 representation of the file is slightly different. Its header chunk:

4D 54 68 64 MThd
00 00 00 06 chunk length
00 01       format 1
00 04       four tracks
00 60       96 per quarter note

4D 54 72 6B MTrk
00 00 00 14 chunk length (20)

Delta-Time	Event	Comments
00	FF 58 04 04 02 18 08	time signature
00	FF 51 03 07 A1 20	tempo
83 00	FF 2F 00	end of track

Then, the track chunk for the first music track. The MIDI convention for note on/off running status is used in this example:

4D 54 72 6B MTrk
00 00 00 10 chunk length (16)

Delta-Time	Event	Comments
00	C0 05	time signature
00	90 4C 20	tempo
83 00	4C 00	Running status: note on, vel=0
00 FF 2F 00		end of track

Then, the track chunk for the second music track:

4D 54 72 6B MTrk
00 00 00 0F chunk length (15)

Delta-Time	Event	Comments
00	C1 2E	time signature
00	91 43 40
83 00	43 00	running status
00 FF 2F 00		end of track ‘eot’

Then, the track chunk for the third music track:

4D 54 72 6B MTrk
00 00 00 15 chunk length (21)

Delta-Time	Event	Comments
00	C2 46	time signature
00	92 30 60
82 20	3C 60	running status
83 00	30 00	two-byte delta-time, running status
00	3C 00	running status
00 FF 2F 00		end of track

Universal System Exclusive Messages

https://www.midi.org/specifications/item/table-4-universal-system-exclusive-messages

The following table lists all currently defined Universal System Exclusive Messages. Universal System Exclusive Messages are defined as Real Time or Non-Real Time, and are used for extensions to MIDI that are NOT intended to be manufacturer exclusive (despite the name).

Many of these messages are defined in Specifications whose printed documentation is available from the MMA. Others are defined in Recommended Practice documentation that may be found on this web site.

WARNING! Details about implementing these messages can dramatically impact compatibility with other products. We strongly recommend consulting the appropriate MMA Specification or Recommended Practice for additional information.

Table: Non-Real Time (7EH)

id1	id2	description
00		Unused
01		Sample Dump Header
02		Sample Data Packet
03		Sample Dump Request
04	nn	MIDI Time Code
	00	Special
	01	Punch In Points
	02	Punch Out Points
	03	Delete Punch In Points
	04	Delete Punch Out Points
	05	Event Start Point
	06	Event Stop Point
	07	Event Start Points with additional info.
	08	Event Stop Points with additional info.
	09	Delete Event Start Point
	0A	Delete Event Stop Point
	0B	Cue Points
	0C	Cue Points with additional info.
	0D	Delete Cue Point
	0E	Event Name in additional info.
05	nn	Sample Dump Extensions
	01	Loop Points Transmission
	02	Loop Points Request
	03	Sample Name Transmission
	04	Sample Name Request
	05	Extended Dump Header
	06	Extended Loop Points Transmission
	07	Extended Loop Points Request
06	nn	General Information
	01	Identity Request
	02	Identity Reply
07	nn	File Dump
	01	Header
	02	Data Packet
	03	Request
08	nn	MIDI Tuning Standard (Non-Real Time)
	00	Bulk Dump Request
	01	Bulk Dump Reply
	03	Tuning Dump Request
	04	Key-Based Tuning Dump
	05	Scale/Octave Tuning Dump, 1 byte format
	06	Scale/Octave Tuning Dump, 2 byte format
	07	Single Note Tuning Change with Bank Select
	08	Scale/Octave Tuning, 1 byte format
	09	Scale/Octave Tuning, 2 byte format
09	nn	General MIDI
	01	General MIDI 1 System On
	02	General MIDI System Off
	03	General MIDI 2 System On
0A	nn	Downloadable Sounds
	01	Turn DLS On
	02	Turn DLS Off
	03	Turn DLS Voice Allocation Off
	04	Turn DLS Voice Allocation On
0B	nn	File Reference Message
	00	reserved (do not use)
	01	Open File
	02	Select or Reselect Contents
	03	Open File and Select Contents
	04	Close File
	05-7F	reserved (do not use)
0C	nn	MIDI Visual Control
	00-7F	MVC Commands (See MVC Documentation)
0D	nn	MIDI Capability Inquiry
	00-7F	Inquiry/Response Messages (See Documentation)
7B	nn	End of File
7C	nn	Wait
7D	nn	Cancel
7E	nn	NAK
7F	nn	ACK

Table: Non-Real Time (7EH)

Table: Real Time (7FH) - Universal System Exclusive Messages

id1	id2	description
00	–	Unused
01	nn	MIDI Time Code
	01	Full Message
	02	User Bits
02	nn	MIDI Show Control
	00	MSC Extensions
	01-7F	MSC Commands (see MSC Documentation)
03	nn	Notation Information
	01	Bar Number
	02	Time Signature (Immediate)
	42	Time Signature (Delayed)
04	nn	Device Control
	01	Master Volume
	02	Master Balance
	03	Master Fine Tuning
	04	Master Coarse Tuning
	05	Global Parameter Control
05	nn	Real Time MTC Cueing
	00	Special
	01	Punch In Points
	02	Punch Out Points
	03	(Reserved)
	04	(Reserved)
	05	Event Start points
	06	Event Stop points
	07	Event Start points with additional info.
	08	Event Stop points with additional info.
	09	(Reserved)
	0A	(Reserved)
	0B	Cue points
	0C	Cue points with additional info.
	0D	(Reserved)
	0E	Event Name in additional info.
06	nn	MIDI Machine Control Commands
	00-7F	MMC Commands (See MMC Documentation)
07	nn	MIDI Machine Control Responses
	00-7F	MMC Responses (See MMC Documentation)
08	nn	MIDI Tuning Standard (Real Time)
	02	Single Note Tuning Change
	07	Single Note Tuning Change with Bank Select
	08	Scale/Octave Tuning, 1 byte format
	09	Scale/Octave Tuning, 2 byte format
09	nn	Controller Destination Setting (See GM2 Documentation)
	01	Channel Pressure (Aftertouch)
	02	Polyphonic Key Pressure (Aftertouch)
	03	Controller (Control Change)
0A	01	Key-based Instrument Control
0B	01	Scalable Polyphony MIDI MIP Message
0C	00	Mobile Phone Control Message

Table: Real Time (7FH) - Universal System Exclusive Messages

MIDI Time Code

https://www.midi.org/specifications-old/item/the-midi-1-0-specification

MIDI Time Code (MTC) is a sub-protocol within MIDI, and is used to keep 2 devices that control some sort of timed performance (ie, maybe a sequencer and a video deck) in sync. MTC messages are an alternative to using MIDI Clocks and Song Position Pointer messages. MTC is essentially SMPTE mutated for transmission over MIDI. SMPTE timing is referenced from an absolute “time of day”. On the other hand, MIDI Clocks and Song Position Pointer are based upon musical beats from the start of a song, played at a specific Tempo. For many (non-musical) cues, it’s easier for humans to reference time in some absolute way rather than based upon musical beats at a certain tempo.

There are several MIDI messages which make up the MTC protocol. All but one are specially defined SysEx messages.

The most important message is the Quarter Frame message (which is not a SysEx message). It has a status of 0xF1, and one subsequent data byte. This message is sent periodically to keep track of the running SMPTE time. It’s analogous to the MIDI Clock message. The Quarter Frame messages are sent at a rate of 4 per each SMPTE Frame. In other words, by the time that a slave has received 4 Quarter Frame messages, a SMPTE Frame has passed. So, the Quarter Frame messages provide a “sub-frame” clock reference. (With 30 fps SMPTE, this “clock tick” happens every 8.3 milliseconds).

But the Quarter Frame is more than just a quarter frame “clock tick”. The Quarter Frame message’s data byte contains the SMPTE time (ie, hours, minutes, seconds, and frames). SMPTE time is normally expressed in 80 bits. Obviously, this is too many bits to be contained in 1 8-bit data byte. So, each Quarter Frame message contains just one piece of the time (for example, one Quarter Frame may contain only the hours). In order to get the entire SMPTE time at any given point, a slave needs to receive several Quarter Frame messages, and piece the current SMPTE time together from those messages. It takes 8 Quarter Frame messages to convey the current SMPTE time. In other words, by the time that a slave can piece together the current SMPTE time, two SMPTE frames have passed (ie, since there are 4 Quarter Frame messages in each frame). So, MTC’s version of SMPTE time actually counts in increments of 2 SMPTE Frames per each update of the current SMPTE time.

The first (of 8) Quarter Frame message contains the low nibble (ie, bits 0 to 3) of the Frame Time. The second Quarter Frame message contains the high nibble (ie, bits 4 to 7) of the Frame Time. The third and fourth messages contain the low and high nibbles of the Seconds Time. The fifth and sixth messages contain the low and high nibbles of the Minutes Time. The seventh and eighth messages contain the low and high nibbles of the Hours Time. The eighth message also contains the SMPTE frames-per-second Type (ie, 24, 25, 30 drop, or 30 fps). If you were to break up the Quarter Frame’s data byte into its 7 bits, the format is:

0nnn dddd

where nnn is one of 7 possible values which tell you what dddd represents. Here are the 7 values, and what each causes dddd to represent.

Value	dddd
0	Current Frames Low Nibble
1	Current Frames High Nibble
2	Current Seconds Low Nibble
3	Current Seconds High Nibble
4	Current Minutes Low Nibble
5	Current Minutes High Nibble
6	Current Hours Low Nibble
7	Current Hours High Nibble and SMPTE Type

Value	Meaning
0xF1 0x25	means that the 5 is the low nibble of the Seconds Time (because nnn is 2). If the following Quarter Frame is subsequently received,
0xF1 0x32	then this means that 2 is the high nibble of the Seconds Time. Therefore, the current SMPTE Seconds is 0x25 (ie, 37 seconds).

In the data byte for the Hours High Nibble and SMPTE Type, the bits are interpreted as follows:

0nnn x yy d

where nnn is 7. x is unused and set to 0. d is bit 4 of the Hours Time. yy tells the SMPTE Type as follows:

yy	fps
0	24
1	25
2	30 (Drop-Frame)
3	30

When MTC is running in the forward direction (ie, time is advancing), the Quarter Frame messages are sent in the order of Frames Low Nibble to Hours High Nibble. In other words, the order looks something like this:

name	value
0xF1 0x0n	where n is the current Frames Low Nibble
0xF1 0x1n	where n is the current Frames High Nibble
0xF1 0x2n	where n etc.
0xF1 0x3n
0xF1 0x4n
0xF1 0x5n
0xF1 0x6n
0xF1 0x7n	When MTC is running in reverse (ie, time is going backwards), these are sent in the opposite order, ie, the Hours High Nibble is sent first and the Frames Low Nibble is last. The arrival of the 0xF1 0x0n and 0xF1 0x4n messages always denote where SMPTE Frames actually occur in realtime.

Since 8 Quarter Frame messages are required to piece together the current SMPTE time, timing lock can’t be achieved until the slave has received all 8 messages. This will take from 2 to 4 SMPTE Frames, depending upon when the slave comes online.

The Frame number (contained in the first 2 Quarter Frame messages) is the SMPTE Frames Time for when the first Quarter Frame message is sent. But, because it takes 7 more Quarter Frames to piece together the current SMPTE Time, when the slave does finally piece the time together, it is actually 2 SMPTE Frames behind the real current time. So, for display purposes, the slave should always add 2 frames to the current time.

For cueing the slave to a particular start point, Quarter Frame messages are not used. Instead, an MTC Full Frame message should be sent. The Full Frame is a SysEx message that encodes the entire SMPTE time in one message as so (in hex):

F0 7F cc 01 01 hr mn sc fr F7

cc is the SysEx channel (0 to 127). It is suggested that a device default to using its Manufacturer’s SysEx ID number for this channel, giving the musician the option of changing it. Channel number 0x7F is used to indicate that all devices on the daisy-chain should recognize this Full Frame message.

The hr, mn, sc, and fr are the hours, minutes, seconds, and frames of the current SMPTE time. The hours byte also contains the SMPTE Type as per the Quarter Frame’s Hours High Nibble message.

The Full Frame simply cues a slave to a particular SMPTE time. The slave doesn’t actually start running until it starts receiving Quarter Frame messages. (Which implies that a slave is stopped whenever it is not receiving Quarter Frame messages). The master should pause after sending a Full Frame, and before sending a Quarter Frame, in order to give the slave time to cue to the desired SMPTE time.

During fast forward or rewind (ie, shuttle) modes, the master should not continuously send Quarter Frame messages, but rather, send Full Frame messages at regular intervals.

SMPTE also provides for 32 “user bits”, information for special functions which vary with each product. (Usually, these bits can only be programmed from equipment that supports such). Upto 4 characters or 8 digits can be written. Examples of use are adding a date code or reel number to a tape. The user bits tend not to change throughout a run of time code, so rather than stuffing this information into a Quarter Frame, MTC provides a separate SysEx message to transmit this info.

F0 7F cc 01 02 u1 u2 u3 u4 u5 u6 u7 u8 u9 F7

cc is the SysEx channel (0 to 127). Only the low nibble of each of the first 8 data bytes is used. Only the 2 low bits of u9 is used.

u1 = 0000aaaa 
u2 = 0000bbbb 
u3 = 0000cccc 
u4 = 0000dddd 
u5 = 0000eeee 
u6 = 0000ffff 
u7 = 0000gggg 
u8 = 0000hhhh 
u9 = 000000ii

These nibbles decode into an 8-bit format of aaaabbbb ccccdddd eeeeffff gggghhhh ii. It forms 4 8-bit characters, and a 2 bit Format Code. u1 through u8 correspond to the SMPTE Binary Groups 1 through 8. u9 are the 2 Binary Group Flag Bits, defined by SMPTE.

The Users Bits messages can be sent at any time, whenever these values must be passed to some device on the daisy-chain.

Notation Information

There are two Notation Information messages which can be used to setup a device that needs to interact with the musician using musical bars and beats.

The Time Signature message can setup Time Signature or indicate a change of meter.

F0 7F cc 03 ts ln nn dd qq [nn dd…] F7

cc is the SysEx channel (0 to 127).

ts is 02 if the Time Signature is to be changed now, or 42 if the Time Signature is to be changed at the end of the currently playing measure.

ln is the number of data bytes following this field. Normally, this will be a 3 if there is not a compound time signature in the measure.

nn dd are the Numerator and Denominator of the Time Signature, respectively. Like with MIDI File Format’s Time Signature MetaEvent, the Denominator is expressed as a power of 2.

qq is the number of notated 32nd notes in a MIDI quarter note. Again, this is similiar to the same field in MIDI File Format’s Time Signature MetaEvent.

[nn dd …] are optional, additional pairs of num/denom, to define a compound time signature within the same measure.

The Bar Marker message indicates the start of a musical measure. It could also be used to setup and mark off bars of an introductory “count down”.

F0 7F cc 03 01 lb mb F7

cc is the SysEx channel (0 to 127).

lb mb is the desired bar number, with the LSB first (ie, Intel order). This is a signed 14-bit value (low 7 bits are in lb, right-justified, and bits 8 to 14 are in mb, right-justified). Zero and negative numbers up to -8,190 indicate count off measures. For example, a value of -1 (ie, lb mb = 7F 7F) means that there is a one measure introduction. A value of zero would indicate no count off. Positive values indicate measures of the piece. The first measure is bar 1 (ie, lb mb = 01 00). A maximum neg number (lb mb = 00 40) indicates “stopped play” condition. A maximum positive value (lb mb = 7E 3F) indicates running condition, but no idea about measure number. This would be used by a device wishing to mark the passage of measures without keeping track of the actual measure number.

Setup Message

The Setup message can be used to implement one of 19 defined “events”. A master device uses this message to tell slave units what “events” to perform, and when to perform those events. Here’s the general template for the message.

F0 7F cc 04 id hr mn sc fr ff sl sm [more info] F7

cc is the SysEx channel (0 to 127).

hr mn sc fr ff is the SMPTE time when the event is to occur. This is just like the Full Frame message, except that there is also a fractional frame parameter, ff, which is $\frac{1}{100}$ of a frame (ie, a value from 0 to 99).

sl sm is this event’s 14-bit Event Number (0 to 16,383). sl is bits 0 to 6, and sm is bits 7 to 13.

id tells what this Event Type is. Depending upon the Type, the message may have additional bytes placed where is. The following values for Event Types are defined, and here’s what each does.

Special (00)

Contains the setup information that affects a device globally, as opposed to individual tracks, sounds, programs, sequences, etc.). In this case, the Event Number is actually a word which further describes what the event is, as so:

Time Code Offset (00 00) refers to a relative Time Code offset for each unit. For example, a piece of video and a piece of music that are supposed to go together may be created at different times, and likely have different absolute time code positions. Therefore, one must be offset from the other so that they will match up. Each slave on the daisy-chain needs its own offset so that all can be matched up to the master’s SMPTE start time.

Enable Event List (01 00) means for a slave to enable execution of events in its internal “list of events” when each one’s respective SMPTE time occurs.

Disable Event List (02 00) means for a slave to disable execution of events in its internal “list of events”, but not to erase the list.

Clear Event List (03 00) means for a slave to erase all events in its internal list.

System Stop (04 00) refers to a time when the slave may shut down. This serves as a protection against Event Starts without Event Stops, tape machines running past the end of a reel, etc.

Event List Request (05 00) is sent by the master, and requests the slave (whose channel matches the message) to send all events in its list as a series of Setup messages, starting from the SMPTE time in this message.

NOTE: For the first 5 Special messages, the SMPTE time isn’t used and is ignored.

Punch In (01) and Punch Out (02)

These refer to the enabling and disabling of record mode on a slave. The Event Number refers to the track to be recorded. Multiple Punch In and Punch Out points (and any of the other Event Types below) may be specified by sending multiple Setup messages with different SMPTE times.

Delete Punch In (03) and Delete Punch Out (04)

Deletes the Punch In or Punch Out (with the matching Event Number and SMPTE Time) from the slave’s event list. In other words, it deletes a previously sent Punch In or Punch Out Setup message.

Event Start (05) and Event Stop (06)

These refer to the start/stop (ie, playback) of some continuous action (ie, an action that begins when an Event Start is received, and continues until an Event Stop is received). The Event Number refers to which action on the slave is to be started/stopped. Such actions may include playback of a specific looped waveform, a fader moving on an automated mixer, etc.

Event Start (07) and Event Stop (08) with additional info

Almost the same as the above 2 Event Types, but these have additional bytes before the final 0xF7. Such additional bytes could be for an effect unit’s changing parameters, the volume level of a sound effect being adjusted, etc. The additional info should be nibblized with the lowest bits first. For example, if the Note On message 0x91 0x46 0x7F was to be encoded in some additional info bytes, they would be 01 09 06 04 0F 07.

Delete Event Start (09) and Delete Event Stop (0A)

Deletes the Event Start or Event Stop (with the matching Event Number and SMPTE Time) from the slave’s event list. In other words, it deletes a previously sent Event Start or Event Stop Setup message (either the Types without additional info, or with additional info).

Cue Point (0B)

Sets an action to be triggered (ie, an action that does something once and automatically stops afterward) or a marker at the specified SMPTE time. These include a “hit” point for a sound effect, a marker for an edit point, etc. The Event Number should represent the action or marker. For example, Event Number 3 could be to trigger a car crash sound effect. Then, several car crashes could be specified by sending several Cue Point Setup messages, each with Event Number 3, but different SMPTE times.

Cue Point (0C) with additional info

Like the above, but this message may have additional bytes before the final 0xF7. Such additional bytes could be for an effect unit’s parameters, the volume level of a sound effect, etc. The additional info should be nibblized with the lowest bits first.

Delete Cue Point (0D)

Deletes one of the preceding 2 Setup messages (with the same Event Number and SMPTE time) from the slave’s event list.

Event Name (0E) with additional info

This assigns an ascii name to the event with the matching Event Number and SMPTE time. It for the musician’s point of reference. The additional info bytes are the ascii name. For a newline character, include both a carriage return (0x0A) and line feed (0x0D). The ascii bytes are nibblized. For example, ascii ‘A’ (0x41) becomes the two bytes, 0x01 0x04.

To summarize the interaction between master and slave depending upon “play mode”:

Play Mode

The master is in normal play at normal or vari-speed rates. The master is sending Quarter Frame messages to the slave. The messages are in ascending order, starting with 0xF1 0x0n and ending with 0xF1 0x7n. If the master is capable of reverse play, then the messages are sent in reverse, starting with 0xF1 0x7n and ending with 0xF1 0x0n.

Cue Mode

The master is being “rocked” or “cued” by hand. For example, a tape machine may have the tape still in contact with the playback head so that the musician can cue the contents of the tape to a specific point. The master is sending Quarter Frame messages to the slave. The messages are in ascending order, starting with 0xF1 0x0n and ending with 0xF1 0x7n. If the master is playing in a reverse direction, then the messages are sent in reverse, starting with 0xF1 0x7n and ending with 0xF1 0x0n. Because the musician may be changing the tape direction rapidly, the order of the Quarter Frames must change along with the tape direction.

Fast Forward or Rewind Mode

The master is rewinding or fast forwarding tape. No contact is made with the playback head. So, no cueing is happening. Therefore, the master only need send the slave periodic Full Frame messages at regular intervals as a rough indication of the master’s position. The SMPTE time indicated by the last Full Frame message actually takes affect upon the reception of the next Quarter Frame message (ie, when Play Mode resumes).

General MIDI Level 2 (1999)

General MIDI Level 2
https://en.wikipedia.org/wiki/General_MIDI_Level_2

GM2 Supported NRPN Parameter Numbers (RPN)

• Pitch Bend Sensitivity
• Channel Fine Tune
• Channel Coarse Tune
• Modulation Depth Range (Vibrato Depth Range)
• RPN NULL

Supported Universal System Exclusive (SysEx) messages

• Master Volume
• Master Fine Tuning
• Master Coarse Tuning
• Reverb Type
• Reverb Time
• Chorus Type
• Chorus Mod Rate
• Chorus Mod Depth
• Chorus Feedback
• Chorus Send to Reverb
• Controller Destination Setting
• Scale/Octave Tuning Adjust
• Key-Based Instrument Controllers
• GM2 System On

Additional Percussion Kit Key-Mappings

027 F1  High Q                     082 A#5 Shaker
028 F#1 Slap                       083 B5  Jingle Bell
029 G2  Scratch Push               084 C5  Belltree
032 G#1 Scratch Pull               085 C#5 Castanets
033 A1  Sticks                     086 D5  Open Surdo
034 A#1 Metronome Bell

BANK 1

Key: [BANK-MSB]:[BANK-LSB] [Patch-Name]

001:001 Wide Acoustic Grand        001:054 Humming                                 
001:002 Wide Bright Acoustic       001:055 Analog Voice    
001:003 Wide Electric Grand        001:056 Bass Hit    
001:004 Wide Honky-tonk            001:057 Dark Trumpet    
001:005 Detuned Electric Piano 1   001:058 Trombone 2    
001:006 Detuned Electric Piano 2   001:060 Muted Trumpet 2    
001:007 Coupled Harpsichord        001:061 French Horn 2    
001:008 Pulse Clavinet             001:062 Brass Section 2    
001:012 Wet Vibraphone             001:063 Synth Brass 3    
001:013 Wide Marimba               001:064 Synth Brass 4    
001:015 Church Bell                001:081 Square Wave    
001:017 Detuned Organ 1            001:085 Wire Lead    
001:018 Detuned Organ 2            001:088 Delayed Lead    
001:020 Church Organ 2             001:090 Sine Pad    
001:021 Puff Organ                 001:092 Itopia    
001:022 Italian Accordion          001:099 Synth Mallet    
001:025 Ukulele                    001:103 Echo Bell    
001:026 12-String Guitar           001:105 Sitar 2    
001:027 Hawaiian Guitar            001:108 Taisho Koto    
001:028 Chorus Guitar              001:116 Castanets    
001:029 Funk Guitar                001:117 Concert Bass Drum    
001:030 Guitar Pinch               001:118 Melodic Tom 2    
001:031 Feedback Guitar            001:119 808 Tom    
001:032 Guitar Harmonics           001:121 Guitar Cut Noise    
001:034 Finger Slap                001:122 Flute Key Click    
001:039 Synth Bass 101             001:123 Rain    
001:040 Synth Bass 4               001:124 Dog    
001:041 Slow Violin                001:125 Telephone 2    
001:047 Yang Qin                   001:126 Car-Engine    
001:049 Orchestra Strings          001:127 Laughing    
001:051 Synth Strings 3            001:128 Machine Gun    
001:053 Choir Aahs 2                    

BANK 2

002:001 Dark Acoustic Grand         002:056 6th Hit
002:005 Electric Piano 1 Variation  002:058 Bright Trombone
002:006 Electric Piano 2 Variation  002:063 Analog Brass 1
002:007 Wide Harpsichord            002:064 Analog Brass 2
002:015 Carillon                    002:081 Sine Wave
002:017 60’s Organ 1                002:082 Doctor Solo
002:018 Organ 5                     002:103 Echo Pan
002:020 Rock Organ                  002:119 Electric Percussion
002:025 Open Nylon Guitar           002:121 Horse-Gallop
002:026 Mandolin                    002:123 Thunder
002:028 Mid Tone Guitar             002:124 Horse-Gallop
002:029 Funk Guitar 2               002:125 Door Creaking
002:031 Distortion Rtm Guitar       002:126 Car-Stop
002:039 Synth Bass 3                002:127 Screaming
002:040 Rubber Bass                 002:128 Lasergun
002:049 60’s Strings                                            

BANK 3

003:005 60’s Electric Piano        003:056 Euro Hit
003:006 Electric Piano Legend      003:063 Jump Brass
003:007 Open Harpsichord           003:082 Natural Lead
003:017 Organ 4                    003:123 Wind
003:025 Nylon Guitar 2             003:124 Bird 2
003:026 Steel + Body               003:125 Door Closing
003:029 Jazz Man                   003:126 Car-Crash
003:039 Clavi Bass                 003:127 Punch
003:040 Attack Pulse               003:128 Explosion

BANKS 4-8

004:006 Electric Piano Phase       005:123 Bubble
004:039 Hammer                     005:125 Wind Chimes
004:082 Sequenced Saw              005:126 Siren
004:123 Stream                     005:127 Footsteps
004:125 Scratch
004:126 Car-Crash
004:127 Heart Beat

006:126 Train                      007:126 Jetplane

008:126 Starship

Additional Standards

Generally GS MIDI Standards foreshadowed what seems to have become
General MIDI Layer 2 (GM2).

Yamaha XG is worth checking out in addition to the XGLite standard.

MIDI Standard Comparison
https://en.wikipedia.org/wiki/Comparison_of_MIDI_standards

DLS (Y—I’m sure you can find much more adequate links)
https://www.loc.gov/preservation/digital/formats/fdd/fdd000118.shtml

Footnotes

1. “The MIDI Association” — https://www.midi.org ↩

2. “Society of Motion Picture and Television Engineers” — https://www.smpte.org ↩

3. “Microseconds” 1,000,000 = 1 microsecond; e.g. µsec, usec, musec ↩