What triggers are

Triggers are MIDI or OSC messages that LTCast fires at specific timecodes. They let you automate external devices — lighting consoles, media servers, DAWs — directly from the show's timeline without running a separate show controller. Each trigger is a precise, repeatable command that fires each time playback passes its timecode position.

Where to find them

Triggers live in the TRIGGERS tab of the right-hand panel. The tab is hidden by default: switch it on with Show Triggers (MIDI) tab under Settings → Workflow → Appearance → Optional panels, or from the View menu in the title bar, under Panels. The tab is part of Pro, and the trial includes it.

How triggers relate to the timeline

Each song in the setlist has its own independent trigger list. When playback reaches a trigger's timecode, LTCast sends the programmed message. Triggers fire independently of cue markers on the waveform — they are a parallel output layer. A cue marker is a visual label for the operator; a trigger is an outbound command to another device. Both can exist at the same timecode position without interfering with each other. Cues and their trigger labels are not triggers: a label such as Manual GO sends nothing.

What a trigger contains

Each trigger has these fields:

• Name — a short description, required, shown on the trigger's row, in the Show Log when it fires and in the cue sheet (e.g., "Lights Q12" or "Resolume clip 4"). It does not appear in the Calling Script tab, which is built from cues only. For an MSC trigger the name is also the cue number that is sent.
• Timecode position — the HH:MM:SS:FF timecode at which the trigger fires
• Type — the message to send: Note, CC, PC, MSC, or OSC
• Parameters — the specific values for that type, such as MIDI channel, note number, or OSC address

Every trigger also has an on/off switch at the left of its row. A trigger that is switched off is skipped, and is left out of the cue sheet.

Trigger MIDI output port

All MIDI triggers for all songs use the same MIDI output port. Choose it in Settings → Outputs → Trigger MIDI port. You can use the same port as the MTC output or a separate dedicated port — whichever matches your rig. If no port is selected, MIDI triggers are silently skipped during playback. OSC triggers do not use this port: they go to the OSC targets in the same settings section, and are skipped unless OSC output is switched on.

Common use cases

Triggers are useful any time you need an external device to change state at a precise timecode moment:

• Launching a specific Resolume Arena clip at the start of a song section
• Firing a lighting scene change on an ETC Eos or Chamsys console
• Triggering a sound effect or stem unmute in a DAW
• Sending an MSC GO command to advance a cue on a professional lighting desk
• Starting a video loop on a media server via OSC