VrchStudio-comfyui-web-viewer/docs/midi_nodes.md

Node: MIDI Device Loader @ vrch.ai (vrch.ai/control/midi)

1. Add the MIDI Device Loader @ vrch.ai node to your ComfyUI workflow.

2. Configure the Node:

   • device_id: Select the MIDI device ID to use. Default is empty (connects to first available device).
   • name: Displays the connected MIDI device name (read-only).
   • refresh_interval: Set the polling frequency in milliseconds (10–10000ms). Default is 100.
   • debug: Enable to view detailed debug information in the console and display raw data. Default is False.
   • raw_data: Shows the raw MIDI state in JSON format (visible only when debug is enabled).

3. Connecting a MIDI Device:

   • Connect a compatible MIDI device to your computer before starting ComfyUI.
   • Ensure your browser supports the Web MIDI API (Chrome and Edge have the best support).
   • The node will automatically connect to the first available device if device_id is not specified.
   • To target a specific device, set the device_id field to the device’s ID and the node will reconnect if that device appears.

4. Data Access:

   • The node polls the connected MIDI device at the specified refresh_interval.
   • Incoming MIDI messages are parsed into CC (Control Change) and Note events.
   • CC and Note data are stored in arrays of length 128 (one slot per MIDI number).

5. Node Outputs:

   • RAW_DATA: Complete MIDI state in JSON format.
   • INT_CC_VALUES: Array of integer CC values (0–127).
   • FLOAT_CC_VALUES: Array of normalized CC values (0.0–1.0).
   • BOOLEAN_NOTE_VALUES: Array of booleans indicating note on (True) or off (False) for each MIDI note number.
   • INT_NOTE_VALUES: Array of integer note velocity values (0–127).

Note:

• Supported message types include Note On/Off, Control Change, Aftertouch, Program Change, Channel Pressure, and Pitch Bend.
• High-end MIDI controllers may send more message types; unsupported types are ignored by default.
• Multiple devices can be handled by adding multiple MIDI Device Loader nodes with different device_id settings.