Drive the OnAirScreen ON AIR LED from a RØDECaster Pro II
The RØDECaster Pro II can turn OnAirScreen LED1 (factory label ON AIR) over USB MIDI. No playout software in between.
This is the mixer itself. Playout GPI howtos (mAirList, ProppFrexx, Myriad, PlayoutONE) are a different path. MIDI settings: User Manual (GPIO → MIDI).
RØDE: MIDI triggers, SMART Pads, RØDECaster App
What the mixer actually sends
| Signal | What MIDI carries | Use for LED1? |
|---|---|---|
| Fader mute button | CC 27, value 1 while the button is held, 0 when released. Channel = fader (1–6) | Yes — one press flips the lamp. MIDI does not say whether the channel is muted |
| SMART Pad, On and Off | Your CC or Note: On while pressed, Off when released | Yes — the lamp follows the finger on the pad |
| SMART Pad, On only (factory pads) | One On message per press, no Off | Only with Toggle (tap on, tap off) |
| Record / Listen / channel select | Other CCs (record is CC 17) | No |
The red mute button on the caster latches. The MIDI message does not. It only reports the finger. A mute from the touchscreen does not move the lamp. OnAirScreen also does not know the mute state at startup.
RØDE’s map lists mute as CC 27, value 1, channels 1–6 (MIDI control reference). The same press/release pattern (1, then 0) is how the REC button is documented. Value 1 is below OnAirScreen’s default CC threshold of 64, so the row stays dark until Threshold is 1.
Connect
1. Plug USB 1 into the computer that runs OnAirScreen. MIDI stays on that USB port. It does not cross the network to another machine.
2. In the RØDECaster App, open the unit → Device Configuration → System and turn MIDI on. The switch is stored on the caster.
3. OnAirScreen: Settings → GPIO → MIDI (same fields in the Web UI). Tick Enable MIDI, refresh the interface list, and pick the caster. RØDE’s docs call that port RØDECaster Pro MIDI (USB 1) or MIDI Function. Use the name that appears. Apply.
Mute button → LED1
Host mic on the left-hand fader. One row:
| Field | Value |
|---|---|
| Name | MIC |
| On | ticked |
| Channel | 1 (fader 1). Fader 2 is channel 2, up to fader 6 on channel 6 |
| Type | CC |
| Number | 27 |
| Threshold | 1 |
| Behavior | Toggle |
| Invert | off (ignored for Toggle) |
| Action | LED1 |
Or press Learn on that row and tap the mute button within 10 seconds. Learn fills channel, type, and number. It does not change Threshold or Behavior — set those to 1 and Toggle yourself.
Apply, then tap mute once. Each press sends LED1:TOGGLE. The release (value 0) does not press again.
The lamp and the red mute light can drift apart: a mute on the screen, or OnAirScreen starting while the mic is already muted, leaves them different. Tap the mute button once to line them up, or click LED1 / press 1.
Optional: add AIR1 on the same row if the mic timer should start and stop with that button. It toggles on the same press, with the same drift.
A second physical mic is another row (channel 2, still CC 27, Threshold 1, Toggle). Point it at LED2, or at LED1 if that second button should flip the same lamp. Two Toggle rows do not mean “on while either mic is open”. Toggle is not a Logic input.
SMART Pad, when the lamp should follow a level
Use this when LED1 must stay on for as long as a control is held, or when several mics should share one lamp through Logic.
In the pad setup, set the action to MIDI → Custom (SMART Pads):
- Type CC or Note
- A number that is not the mute CC you already use
- On and Off — On when pressed, Off when released
- On value 127 (any value at or above the OnAirScreen threshold)
OnAirScreen row: Learn while you press the pad, Behavior On/Off, Threshold 64 (or 1 if that pad’s On value is 1). Action LED1. Apply. The lamp is on only while the pad is down.
Factory pads send an On-only CC on channel 1 (pad 1 of bank 1 is CC 0, then 1, 2, …). That has no Off, so Behavior On/Off would turn the lamp on and leave it on. For a tap-on / tap-off pad, use Toggle instead.
Several held pads → one lamp: set each of those rows to On/Off, leave Action empty, and on Settings → GPIO → Logic add a rule OR with those MIDI inputs and output LED1. Only On/Off rows show up there.
Notes
- RØDECaster Duo uses the same mute CC 27, on channels 1–4.
- Debounce (default 20 ms) only groups Oneshot and Toggle bursts. Leave it.
- Two enabled rows on the same channel, type, and number both fire, and the MIDI tab warns.
- Questions: Contact
Other LED howtos
mAirList · ProppFrexx · Myriad Playout · PlayoutONE · RØDECaster Pro II (MIDI)
Titles: mAirList · RadioBOSS · RadioDJ · PlayoutONE · StationPlaylist · ProppFrexx · Myriad Playout · RCS Zetta