# Configuration Slots
The MVP supports **5 independent configuration slots** (A through E) for Video, Lighting, and Timecode. Slots let you prepare multiple show configurations and switch between them instantly -- even during a live performance.
***
## What Are Slots?
Each slot is a separate bank of MIDI note-to-clip assignments. For example:
* **Slot A**: Verse visuals and ambient lighting
* **Slot B**: Chorus visuals and high-energy lighting
* **Slot C**: Acoustic set with different video clips
* **Slot D**: Backup configuration
* **Slot E**: Rehearsal/test clips
When you switch from Slot A to Slot B, all the MIDI note assignments change to Slot B's configuration. Note 1 might trigger "ocean.mp4" in Slot A but "fireworks.mp4" in Slot B.
***
## Independent Slots
**Video, Lighting, and Timecode slots are fully independent.** You can have:
* Video on Slot B
* Lighting on Slot D
* Timecode on Slot A
Each media type has its own A-E slot selection, stored independently on the device.
***
## Switching Slots from the UI
On the Video, Lighting, and Timecode pages, click the **slot name** in the header to expand the slot selector. Click any slot to switch.
### Video and Lighting Slots
* After switching, click **"Sync Changes to Playback"** to apply the new slot's assignments.
* If you have unsaved changes, you'll be prompted to Sync, discard, or cancel.
### Timecode Slots
* Slot switches take effect **immediately** -- saving auto-syncs to playback. There is no separate "Sync Changes" step.
* If you have unsaved changes on the current slot, they are saved automatically before switching.
### Renaming Slots
Click the **pencil icon** next to a slot to rename it. Names can be up to **30 characters** using letters, numbers, spaces, underscores, dashes, dots, parentheses, and ampersand.
***
## Switching Slots via MIDI (Live Performance)
During a live show, you can switch **Video and Lighting** slots using **MIDI CC #119** without touching the browser:
| CC #119 Value | Slot |
| ------------- | ------ |
| 10 | Slot A |
| 20 | Slot B |
| 30 | Slot C |
| 40 | Slot D |
| 50 | Slot E |
**Important details:**
* Send CC #119 on the **video MIDI channel** to switch the video slot
* Send CC #119 on the **lighting MIDI channel** to switch the lighting slot
* Video and lighting switch **independently** based on which channel receives the CC
* **Value 0 is ignored** (common DAW reset value that would otherwise cause unintended switches)
* **Only the exact values above are accepted** -- values like 11, 25, or 35 are ignored
* If the requested slot is already active, the switch is silently skipped
* **Timecode does not support MIDI CC slot switching** -- timecode slots can only be changed from the UI
### Example: Switching Slots from a DAW
In your DAW's MIDI track:
1. At the point where you want to switch to Slot B, insert a **CC #119 message with value 20** on the video MIDI channel.
2. The MVP will switch to Slot B immediately -- subsequent MIDI note triggers will use Slot B's assignments.
### Example: Switching Slots from a Controller
If your MIDI controller has knobs or buttons that send CC messages:
1. Assign a button to send **CC #119** on the appropriate channel.
2. Set the value for each button: 10 for A, 20 for B, etc.
3. Press the button during the show to switch slots.
***
## What Happens When You Switch Slots?
* The new slot's MIDI assignments become active **immediately** -- no loading delay
* The currently playing clip **continues playing** (it doesn't stop or restart)
* The next MIDI note trigger will use the new slot's assignments
* A "Slot Changed" toast notification appears on the physical Status Display
* The Dashboard shows the new active slot
### Slot Status Indicators
When a MIDI CC #119 switch changes the active slot during a show, the Dashboard shows a **lightning bolt icon** next to the slot name with the tooltip "Slot changed via MIDI." The Lighting/Video page headers also display warning chips when the slot you're viewing in the UI differs from the slot that's actively being used for playback.
Timecode slots work more simply. Switching always takes effect immediately with no separate sync step.
***
## Editing Slot Contents
Each slot's assignments are edited independently:
1. Select the slot (A-E) on the relevant page
2. Enable **Edit Mode**
3. Make your assignments (assign files to MIDI notes, or place clips on the timeline)
4. **Video/Lighting**: Click **Sync Changes to Playback**
5. **Timecode**: Click **Save Changes** (auto-syncs)
Changes to one slot do not affect other slots.
***
## Related Pages
* [Video Configuration](/2.-video-setup/video-configuration.md) -- Video slot setup
* [Lighting Configuration](/3.-lighting-setup/lighting-configuration.md) -- Lighting slot setup
* [The Timeline Editor](/4.-timecode-setup/the-timeline-editor.md) -- Timecode slot setup
* [MIDI Reference](/8.-reference/midi-reference.md) -- CC #119 reference
* [Triggering Overview](file:///5753738/5.-Triggering/triggering-overview.md) -- All trigger methods
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