(n.) Musical Instrument Digital Interface system message; a message read by all devices connected to the system, unlike a channel voice or a mode message. The three types of MIDI messages—System Common, System Realtime, and System Exclusive—are defined as follows:
- System Common: Messages include MIDI time code (MTC) or Quarter Frame, Song Position and Song Select to control sequences, and Tune Request.
- System Realtime: Messages include the MIDI Clock timing pulse; Start, Stop, or Continue a sequence; Active Sensing to confirm a connection; and System Reset to return all devices to their default statuses.
- System Exclusive: Messages carry a manufacturer ID that only one brand of equipment recognizes. This type of message includes the Sample Dump Standard, which allows nonexclusive descriptions of waveforms; these can be edited and played back on different brands of sample players. It also includes MTC messages, which can be used to synchronize with SMPTE devices. The MIDI file standard allows a sequence to be read by any type of MIDI device, regardless of the platform. The file format is the Standard MIDI File (SMF).