Apple Logic Pro 8 User Manual
Page 839
Chapter 36
Synchronizing Logic Pro
839
Transmit MTC (MIDI Time Code)
The checkbox activates transmission of MIDI time code. The menu determines the MIDI
output port for the MTC signal.
If you can avoid it, you shouldn’t send MTC to all ports, as it is very data-intensive. If
possible, use a MIDI port that isn’t being used for anything else.
Transmit MMC (MIDI Machine Control)
Turn on this checkbox to enable transmission of MIDI Machine Control (see “
” on page 844). These commands are then sent whenever you operate
the transport functions (Start, Stop, Rewind, and so on) of Logic Pro.
MMC is normally used when Logic Pro is running as a slave to an external master (such
as an ADAT), and you want to control the external master’s transport functions from
Logic Pro. Logic Pro therefore acts as MMC master, and MTC slave simultaneously.
If you want to use the external master’s transport controls, you don’t need to use MMC.
In this situation, Logic Pro will follow the MTC master as a slave.
You can also use MMC to place tracks on the MMC slave device into record-enabled
mode.
Listen to MMC Input
If this checkbox is activated, Logic Pro can be controlled by MMC (MIDI Machine
Control) and so-called Full Frame Messages.
Logic Pro recognizes these commands when listening to MMC Input:
 Play
 Deferred Play
 Stop
Deferred Play is a special command for mechanically slow synchronization slaves such
as reel-based tape recorders. Rather than having the machine play immediately, it is
asked to reach the desired SMPTE position before playback is started. You’ll find no
difference in Logic Pro’s response to the Play and Deferred Play commands, as Logic Pro
can locate to any position almost instantly.
Logic Pro ignores these messages when incoming external MTC (MIDI Time Code)
commands are detected.
Logic Pro also obeys Full Frame Messages, and sets the playhead to a new location,
without starting playback. Once again, incoming MTC data has higher priority, if
conflicting information is received.