MIDI Clock Synchronization project settings in Logic Pro for iPad
Clock
Mode pop-up menu: Determines the MIDI clock transmission mode for synchronized MIDI devices.
Send Song Position Pointer: MIDI clock is sent with a Song Position Pointer and a Continue command to begin sequencer playback, so that clock receivers with their own song structure can follow your project’s playhead position.
Restart Clock at Pattern Start: MIDI clock is sent without a Song Position Pointer command, which is ideal for step sequencers or drum machines in pattern mode. When repositioning the playhead, MIDI clock restarts at the beginning of the next pattern.
Pattern Length (Bar) field: Determine the length of the pattern by the number of bars.
This parameter is only displayed when you choose Restart Clock at Pattern Start from the Mode pop-up menu.
Clock start
Bar Position field: Defines the musical position at which the MIDI clock output should start. Every time you start playback, a Song Position Pointer (SPP) message is also sent. Because not all devices can process SPP, the MIDI system real-time Continue message is also sent. The exception is when you start at position 1 1 1 1. In this situation, the real-time Start message is sent.
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