MCU MIDI COM v0.79

Universal MIDI Learn and hardware-control bridge for Renoise

MCU MIDI COM turns a compatible MIDI hardware controller into a configurable control surface for Renoise. It provides dedicated encoder, fader and button pages, three target-mapping banks, universal MIDI Learn, automatic song-based mapping persistence and optional realtime cooperation with HYDRA SANITY.

The tool was originally developed for the Nektar Panorama T4 and T6. Its MCU MIXER profile remains optimized for the Panorama MCU layout, but the INTERNAL profile and universal MIDI Learn also allow other MIDI controllers, including Arturia devices, to be used.

The current release was developed and tested with Renoise 3.5.4 and Lua API 6.2.

Quick Start

1. Open MCU MIDI COM from the Renoise Tools menu. Opening the GUI also starts the engine.
2. Press Show MIDI Setup if the MIDI port panel is hidden.
3. Select the hardware control input in P2 CTRL. Select its output as well when MIDI LED feedback is required.
4. Choose MCU MIXER for a compatible MCU layout, or INTERNAL for a standard MIDI controller that will use MIDI Learn.
5. Press Show MIDI LEARN and learn the required ENC, FAD and BTN slots.
6. Select GUI 4 or GUI 8.
7. Choose a Fader Mode, an Encoder Mode and a target BANK.
8. Use STOP ENGINE before closing a completed session. It performs the final silent mapping save.

MCU MIDI COM loads the saved song mapping automatically when the engine starts. Manual SAVE Mapping and LOAD Mapping buttons are no longer required.

1. Introduction

MCU MIDI COM separates physical MIDI hardware from Renoise targets.

The physical layer determines which MIDI message controls ENC1–8, FAD1–9, BTN1–8 and the additional control buttons. The target layer determines which Renoise track, DSP, instrument parameter or action is controlled by each slot.

This separation makes it possible to:

• use one controller with several Renoise target layouts;
• change targets without re-learning the hardware;
• keep three independent BANK 1–3 configurations;
• use either the prepared Panorama MCU layout or a custom MIDI controller;
• connect encoder automation to HYDRA SANITY without giving HYDRA SANITY direct ownership of the same hardware port.

The main control groups are:

2. Basic MIDI Hardware Setup — Show MIDI Setup

Press Show MIDI Setup to display the three MIDI port roles. The button changes to Hide MIDI Setup while the panel is visible.

MIDI port roles

The Nektar Panorama exposes several USB MIDI endpoints. MCU MIDI COM supports the Nektar MIDI device/port 1–3 arrangement by keeping performance, controller and bridge traffic in separate roles.

Panorama T4/T6 in MCU MIXER mode

For the prepared Panorama MCU profile:

• put the Panorama into its physical MIXER / MCU-compatible mode;
• route the controller endpoint to USB port 2 on the Panorama;
• select MIDIIN2 (PANORAMA T4/T6) as P2 CTRL input;
• select MIDIOUT2 (PANORAMA T4/T6) as P2 CTRL output when button LED feedback is required.

The exact device name can vary slightly with the operating system and driver.

Standard MIDI controller mode

When the connected hardware is used only as a MIDI controller, its control data must be assigned to P2 CTRL.

Example for Arturia:

• select the Arturia MIDI input as P2 CTRL input;
• select the Arturia MIDI output as P2 CTRL output only if the device supports feedback that matches the active mapping;
• press INTERNAL;
• use Show MIDI LEARN to assign the Arturia controls to ENC, FAD and BTN slots.

The same procedure applies to other standard MIDI controllers.

P1 PERF is intentionally reserved for Renoise-native performance input. MCU MIDI COM stores the selected P1 name but does not open P1 as a second direct controller input. This avoids mixing note-performance traffic with the control-surface path.

MIDI device selections are stored in the tool preferences. If a device is changed while the engine is running, the corresponding P2 or P3 port is rebound immediately.

3. Universal MIDI Learn — Show MIDI LEARN

Press Show MIDI LEARN to display the Learn row above each ENC, FAD and BTN control. Hiding the Learn rows does not disable or delete their assignments.

Each Learn row contains:

Learning an encoder

1. Select INTERNAL when learning a standard MIDI controller.
2. Press L for the required ENC slot.
3. Move the encoder in both directions.

For a relative encoder, MIDI Learn waits until it detects both directions on the same CC, channel and port. The supported INTERNAL relative range is:

• increase: values 1–20;
• decrease: values 107–127.

An absolute CC encoder is recognized when the movement reaches values inside 21–106. The detected mode is stored with the mapping, so a relative encoder is not treated as an absolute knob later.

Learning a fader

FAD Learn accepts:

• absolute MIDI CC;
• 14-bit Pitch Bend.

Learned absolute CC faders use the inverted direction required by the Renoise automation-graph orientation. Pitch Bend faders keep their native direction.

Learning a button

BTN Learn accepts CC and Note messages. It automatically distinguishes the common behaviors:

• a release received within one second is stored as momentary;
• no release within one second is stored as toggle;
• an initial value 0 is treated as a toggle-style message;
• Note On/Note Off is stored as a Note button.

Reset and persistence

R disables the selected assignment without restoring an MCU default. The reset survives STOP ENGINE, a later START ENGINE and reopening the song. Press L to learn the slot again.

ENC/FAD/BTN mappings are stored with the song. Additional SETUP CONTROLL TOOL mappings and MIDI-port preferences are stored in the tool preferences.

4. INTERNAL and MCU Compatibility

MCU MIXER and INTERNAL are hardware-mapping banks. They are independent from target BANK 1–3.

MCU MIXER

MCU MIXER writes the prepared MCU-compatible layout into the MIXER hardware bank:

This profile is intended for the Panorama T4/T6 physical MIXER mode and controllers with the same MCU message layout. It also provides compatible Note LED feedback through P2 CTRL OUT.

Pressing MCU MIXER rewrites the MIXER hardware bank with these defaults. Use it deliberately if custom assignments already exist in that bank.

INTERNAL

INTERNAL activates the customizable standard-MIDI hardware bank. Its initial prepared assignments are:

These values are starting points, not a restriction. Universal MIDI Learn can replace them with messages from Arturia or another MIDI controller.

The last selected hardware bank is remembered. Switching between MCU MIXER and INTERNAL changes the active hardware interpretation; it does not erase the Renoise targets stored in BANK 1–3.

5. GUI 4 and GUI 8

The two GUI buttons select how many main hardware slots are visible and active.

FAD9 / the Master fader lane remains visible and active in both layouts.

GUI 4 is an operational mode, not only a visual resize. While it is active, slots 5–8:

• do not receive MIDI control messages;
• do not keep active Renoise parameter observables;
• do not send MCU button feedback;
• do not keep active W.A. communication with HYDRA SANITY;
• cancel a pending Learn or encoder-write event that belongs to a hidden slot.

Their learned MIDI messages, target assignments, BANK 1–3 data and stored W.A./LCK states remain in memory. Returning to GUI 8 reactivates the preserved configuration.

The selected GUI size is stored in preferences. Existing configurations default to GUI 8.

6. BANK 1–3

BANK 1, BANK 2 and BANK 3 are independent Renoise target profiles. Use < BANK and BANK > to move between them.

Each bank can preserve its own:

• Fader Mode and Encoder Mode;
• Mixer and FADER #DSP ONLY target selections;
• Track DSP mapping;
• Instrument-slot mapping;
• Master 1–3 mappings;
• Buttons Mode and USER targets;
• W.A. and LCK states.

In Mixer Fader Mode, changing the bank also moves the fader track range by eight tracks. In custom target modes, each bank restores its explicitly stored track, device and parameter selections.

When changing banks, MCU MIDI COM safely detaches the outgoing HYDRA SANITY W.A. state, restores the next bank and then attaches the active targets from that bank. This prevents one bank from leaving a parallel automation owner behind.

Important distinction:

• MCU MIXER / INTERNAL selects the physical MIDI message map.
• BANK 1–3 selects the Renoise target map.

The same learned hardware can therefore operate three completely different Renoise layouts.

7. Fader Modes

The Fader Mode menu contains Mixer, FADER #DSP ONLY and Clear Current.

Mixer

Mixer mode follows the active track bank. Each fader resolves the Renoise Mixer device on its assigned track.

• The default parameter is Volume.
• A different Mixer parameter can be selected for each fader.
• The selected parameter name is remembered per bank and slot.
• BTN1–8 follow the FAD1–8 track assignments in USER, MUTE and SOLO modes.

FADER #DSP ONLY

This mode lets every fader select its own:

1. Renoise track;
2. DSP device;
3. automatable parameter.

Only DSP devices or Send devices whose displayed name begins with # are listed. Rename a Renoise DSP, for example, to #Filter or #Delay to expose it to this mode.

The target list refreshes automatically when an assigned track receives these changes:

• a DSP is inserted or removed;
• DSP order changes;
• a DSP is renamed with or without the # prefix;
• an existing #DSP name changes.

A valid selected device and parameter are preserved by their actual Renoise object identity. If the selected target is deleted or loses the # prefix, Device and Parameter safely return to --.

Tracks without an eligible #DSP also show --; an assigned instrument is not required for FADER targets.

Clear Current

Clear Current clears only the currently active fader-mode mapping. It does not reset MIDI Learn or the other target banks.

8. Encoder Modes

The Encoder Mode menu contains Track DSP, Instrument, Master 1, Master 2, Master 3 and Clear Current.

Every encoder page also provides:

Without W.A., the encoder still changes its resolved Renoise parameter directly. W.A. is specifically the automation-writing bridge to HYDRA SANITY.

Track DSP

All ENC slots operate on the current Renoise track. Each ENC slot can select its own DSP and parameter from that track.

When the selected track changes in Renoise, MCU MIDI COM automatically:

1. detects the selected-track change;
2. loads the new track’s current DSP chain;
3. rebuilds all ENC Device and Parameter lists;
4. reapplies the active-bank ENC mapping to the new track;
5. restores the stored W.A./LCK state for that track where available;
6. publishes the new target identity to HYDRA SANITY.

This means the encoder page follows Renoise track navigation without requiring a manual page switch. If the new track does not contain a compatible device or parameter at the stored selection, that target safely becomes --.

The Track selector in the page header also changes the selected Renoise track, so the same automatic remapping path is used.

Instrument

All ENC slots control one selected Renoise instrument.

1. Select the instrument in Renoise or with the Instrument popup.
2. Press LOAD Host Automation.
3. MCU MIDI COM loads the instrument plugin’s automatable parameters.
4. The first available parameters are assigned to ENC1–8 and can then be changed individually.

Instrument mappings are cached per selected instrument and restored automatically when the Renoise instrument selection changes.

For HYDRA SANITY W.A. operation, the current track must contain the corresponding *Instr. Automation target. When several identical matches exist, select the intended automation device in Renoise first.

Master 1, Master 2, Master 3

These are three independent eight-encoder mapping pages. They are not limited to the Renoise Master track.

Each encoder can select any:

• track;
• DSP device;
• parameter.

The FOLLOW button on one encoder slot makes that slot follow the selected Renoise track. Changing tracks then rebuilds that slot for the new track while preserving its per-track target cache where possible. Only one FOLLOW slot is active on a Master page at a time.

Clear Current

Clear Current clears only the currently active Encoder Mode page in the current bank. Other Encoder Modes, MIDI Learn assignments and other banks remain unchanged.

9. Buttons Modes

BTN1–8 use one shared Buttons Mode. Choose USER, MUTE, SOLO or ARM in the Buttons Page.

The selected Buttons Mode and USER targets are stored per target bank.

Compatible MCU Note LED feedback follows the current button state through P2 CTRL OUT. In ARM mode, the hardware button activates the corresponding HYDRA SANITY Panorama row action.

The separate F9 hardware button is local to the fader section and is not part of the four B1–8 Buttons Modes.

10. SETUP CONTROLL TOOL

SETUP CONTROLL TOOL extends the main ENC/FAD/BTN layout with additional learned hardware buttons. It was designed around the dedicated control buttons available on the Panorama T4/T6, while the Learn mechanism can also accept CC or Note buttons from another controller connected through P2 CTRL.

The dialog contains prepared positions for:

• TRACK -, TRACK +, BROWSE, VIEW;
• BANK -, BANK +, ZOOM -, ZOOM +;
• Repeat, Rewind, Fast Forward, Stop, Play and Record.

Press a displayed control button to start Learn for that position. It changes to PRESS B; then press the required physical hardware button. The learned MIDI type, number and channel are shown below it.

Clear All MIDI Learn in this dialog clears only the additional SETUP CONTROLL TOOL assignments and their HS routing states. It does not clear the main ENC/FAD/BTN assignments.

Current actions

• BANK - and BANK + switch MCU MIDI COM BANK 1–3 locally.
• Transport-row positions can be switched to HS routing individually.
• With HS enabled, Repeat sends the HYDRA SANITY DEL TRACK NOTE / GO TO ROW 00 command.
• With HS enabled, Stop controls HYDRA SANITY Safe Play.
• With HS enabled, Play controls HYDRA SANITY REC Automation.
• With HS enabled, Record controls HYDRA SANITY REC Note & Automation.
• Rewind and Fast Forward HS positions are currently reserved.
• Track, Browse, View and Zoom positions currently provide learned button/state detection and remain prepared for further local actions.

SETUP CONTROLL TOOL mappings are stored in preferences, so the physical Panorama T4/T6 control buttons can remain available across songs while the main target maps remain song-specific.

11. MCU MIDI COM and HYDRA SANITY

MCU MIDI COM and HYDRA SANITY have separate responsibilities:

The current MCU MIDI COM v0.74 implementation is compatible with HYDRA SANITY v8.85. The two tools exchange runtime data over a local OSC connection.

Encoder W.A. workflow

1. Select an ENC target in Track DSP, Instrument or Master mode.
2. Enable W.A. for that encoder.
3. MCU MIDI COM publishes the track, DSP, parameter and encoder-slot identity.
4. HYDRA SANITY creates or updates the corresponding PANORAMA_E1–8 row.
5. Encoder movement is sent to the HYDRA SANITY automation writer.
6. Relative encoder startup can synchronize with the current graph value before applying movement.

LCK keeps the Panorama target protected in HYDRA SANITY and forces W.A. on. ARM Buttons Mode sends the matching encoder-row ARM action.

Changing a target, bank, Renoise track or GUI 4/8 layout publishes the corresponding state transition so HYDRA SANITY does not keep an obsolete target active.

The hardware controller should normally be assigned to MCU MIDI COM P2 CTRL. HYDRA SANITY receives the resulting Panorama control data through OSC; it does not need to open the same Panorama control port a second time. HYDRA SANITY can still use its own MIDI MAPPER for other controllers and global functions.

Both tools must be running for W.A., LCK, ARM and HS-routed SETUP CONTROLL TOOL commands to work.

12. Development Status and Hardware Scope

MCU MIDI COM is still under active development.

The tool was originally created for the Nektar Panorama T4 and T6, including their multiple MIDI endpoints, MCU control layout and additional hardware buttons. Universal MIDI Learn now makes it possible to use other MIDI hardware as well, including Arturia and other controllers that send supported CC, Note or Pitch Bend messages.

Hardware compatibility has two levels:

• MCU MIXER is the prepared profile for the Panorama-compatible MCU message layout.
• INTERNAL is the recommended path for other controllers and custom MIDI presets.

Different controllers can use different relative-encoder formats, button release values and feedback protocols. MIDI input can usually be learned, but MCU LED feedback is only available when the device accepts the feedback format sent by the active profile.

Current development limitations include the reserved SETUP CONTROLL TOOL actions described above. Test a new controller setup on a copy of the song before relying on it in a live performance.

When reporting a problem, include:

• MCU MIDI COM version;
• Renoise version and operating system;
• exact MIDI hardware model and hardware mode;
• selected P2 CTRL input/output;
• MCU MIXER or INTERNAL;
• GUI 4 or GUI 8;
• target BANK, Fader Mode, Encoder Mode and Buttons Mode;
• the exact action sequence and observed result.

Persistence Summary

See MCU_MIDI_COM_CHANGELOG.md for release changes.