M1 v4.2.1 MIDI 1.0 Detailed Specification 96-1-4
MIDI, the Musical Instrument Digital Interface, was established as a hardware and software specification which would make it possible to exchange information (musical notes, program changes, expression control, etc.) between different musical instruments or other devices such as sequencers, computers, lighting controllers, mixers, etc. This ability to transmit and receive data was originally conceived for live performances, although subsequent developments have had enormous impact in recording studios, audio and video production, and composition environments.
This 1996 revision of the MIDI 1.0 specification includes:

• MIDI 1.0 Data Format
• Core Layout of all MIDI 1.0 Messages (Channel Voice Messages, System Messages, Universal System Exclusive)
• Original 5 pin DIN serial Transport
• Some of the Enhancements added to MIDI 1.0 from 1983 to 1996.

Other enhancements to MIDI 1.0 are available as separate specification downloads from this site. MIDI 2.0 specifications, which rely on this MIDI 1.0 specification, are also available on this site.

RP-004-008_v4-2-1_MIDI_Time_Code_Specification_96-1-4.pdf

For device synchronization, MIDI Time Code uses two basic types of messages, described as Quarter Frame and Full. There is also a third, optional message for encoding SMPTE user bits. 

RP-013_v1-0_MIDI_Machine_Control_Specification_96-1-4.pdf

MIDI Machine Control is a general purpose protocol which initially allows MIDI systems to communicate with and to control some of the more traditional audio recording and production systems. Applications may range from a simple interface through which a single tape recorder can be instructed to PLAY, STOP, FAST FORWARD or REWIND, to complex communications with large. time code based and synchronized systems of audio and video recorders. digital recording systems and sequencers. Considerable expansion of the MIDI Machine Control protocol is realizable in the future, and many diverse audio, visual and mixed media devices may thus be brought together under a single general purpose control umbrella.

RP-002-014_v1-1-1_MIDI_Show_Control_Specification_96-1-4.pdf
The purpose of MIDI Show Control is to allow MIDI systems to communicate with and to control dedicated intelligent control equipment in theatrical, live performance, multi-media, audio-visual and similar environments.

Applications may range from a simple interface through which a single lighting controller can be instructed to GO, STOP or RESUME, to complex communications with large, timed and synchronized systems utilizing many controllers of all types of performance technology.