SYSTEM REAL TIME MESSAGES

1. The System Real Time messages are for synchronizing all of the system in real time.
2. The System Real Time messages can be sent at any time. Any messages which consist of two or more bytes may be split to insert Real Time messages.
3. Timing clock (F8H)

The system is synchronized with this clock, which is sent at a rate of 24 clocks/quarter note.
4. Start (from the beginning of song) (FAH)

This byte is immediately sent when the PLAY switch on the master (e.g. sequencer or rhythm unit) is pressed.
5. Continue (FBH)

This is sent when the CONTINUE switch is hit. A sequence will continue at the time of the next clock.
6. Stop (FCH)

This byte is immediately sent when the STOP switch is hit. It will stop the sequence.
7. Active Sensing (FEH)

Use of this message is optional, for either receivers or transmitters. This is a "dummy" Status byte that is sent every 300 ms (max), whenever there is no other activity on MIDI. The receiver will operate normally if it never receives FEH. Otherwise, if FEH is ever received, the receiver will expect to receive FEH or a transmission of any type every 300 ms (max). If a period of 300 ms passes with no activity, the receiver will turn off the voices and return to normal operation.
8. System Reset (FFH)

This message initializes all of the system to the condition of just having turned on power. The system Reset message should be used sparingly, preferably under manual command only. In particular, it should not be sent automatically on power up.