Apple Logic Pro X on the same computer via MTC & MMC
The following explanation and screenshots are related to Logic Pro X version 10.4.5, but the steps will be similar for other versions.
Video Sync features virtual MIDI ports, which mostly removes the need to create network MIDI sessions in Audio MIDI Setup in order to connect to a DAW on the same computer. When Video Sync is launched, it will create virtual MIDI ports named Video Sync MTC In, Video Sync MMC In & Video Sync Trigger In - which will automatically be pre-selected in Video Sync, & visible in your DAW.
For this reason, it is advised to always launch Video Sync before launching the DAW. Failure to do so, may cause some of these settings to be reset to default - such that they need to be re-configured in Logic Pro X® again.
Some DAWs like Cubase for example do not reconnect the virtual ports automatically if Video Sync is opened after the DAW. In cases where this happens often, it may be better to consider setting up ports via Audio MIDI Setup on the same computer.
Video Sync MTC / MMC Setup
First in Video Sync, go to the SYNC tab in Preferences & set the Sync Method field to MIDI.
Next, make sure that all the ports are set to their default values Video Sync MTC In (virtual) & Video Sync MMC In (virtual) as per the image below:
Logic Pro X MTC (MIDI Timecode) Setup
With a project opened, go to File > Project Settings > Synchronization > MIDI tab
In the first unused row, enable MTC & select Video Slave MTC In (virtual).
For versions of Logic Pro X prior to version 10.4.5, this window appears differently - with the same corresponding settings. Enable the Transmit MTC checkbox and select Video Slave MTC In (virtual) from the dropdown menu underneath.
Logic Pro X MMC (MIDI Machine Control) Setup
Still in File > Project Settings > Synchronization > MIDI tab, in the first unused row, enable MMC & select Video Slave MTC In (virtual).
For versions of Logic Pro X prior to version 10.4.5, this window appears differently - with the same corresponding Transmit MMC setting enabled as follows:
Enabling Synchronised playback
The incoming timecode and the timecode rate should now be seen incrementing in the SYNC tab of the Preferences window when hitting play or scrubbing within Logic Pro X.
Click the Sync button to the left of the transport buttons to follow external sync - so that it turns blue.
Video Sync MTC/MMC sync is now online & ready to go. Hit play in Logic Pro X® and Video Sync will play back in sync.
Dealing with MTC sync with high frame rate content
Video Sync allows for synchronised playback of clips running at up to 60 frames per second. Being a standard from the 80s, MIDI timecode (MTC) does not support frame rates higher than 30 frames per second. To be able to play timelines with these high frame rate clips in sync to MTC, Video Sync will try to match the incoming TC at half the frame rate. For example, if the timeline has a 50fps clip, Video Sync will play it in sync if a 25fps MTC source is supplied.
In the timeline list, the timeline frame rate is shown here: