 MIDI Machine Control (MMC) consists of a set of SysEx commands that operate the transport controls of hardware recording devices.MMC lets a sequencer send "Start", "Stop", and "Record" commands to a connected tape deck or hard disk recording system, and to fast-forward or rewind the device so that it starts playback at the same point as the sequencer.No synchronization data is involved, although the devices may synchronize through MTC.