I remember this was awkward to set up at first. Look at Logic Help or the manual for how to get your Synchronisation options window open...because even finding that is not as clear as some things in Logic.
Once you have that opened go to the MIDI section. Go to the Transmit MIDI Clock line. Set up the midi output you want to send the signal from...I use All, & click the square grey button so it has an X over it. (A strange bit in Logic's otherwise good interface......I'd normally think of an X like that as "no","off" or "wrong".
On the MPC set MIDI/SYNC mode to Midi Clock.
That should work....just using midi clock.
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After writing that a few hours back I've been playing around with syncing my MPC to Logic. I should add that you need to reset the syncing for each Logic song unless your Autoload song is set up like this. Also, the MPC doesn't seem to like it if the start point of your Logic song is a negative number....like if you set it back a bar to start at -1, which is something I often do....
