By adding a Synchronization peripheral to your Avid HDX, HD Native, or Pro Tools|HD system, you can use Pro Tools as the master device in your synchronization setup. All other devices are then slaved to Pro Tools.
You can use Pro Tools in conjunction with a Synchronization peripheral to generate LTC, MIDI Timecode, or MMC commands. When the SYNC peripheral is reading incoming SMPTE timecode, it regenerates the timecode through the LTC or MTC output connector. This signal can be passed along to other slave devices.