NT Grids for Disting NT

A port of Emilie Gillet's renowned Mutable Instruments Grids topographic drum sequencer for the Expert Sleepers Disting NT platform.

History & Acknowledgements

This project brings the unique algorithmic drum pattern generation of the original Mutable Instruments Grids module to the Disting NT. Grids is described as a "topographic drum sequencer" - it generates a variety of drum patterns based on continuous interpolation through a "map" of patterns (Drum Mode) or using Euclidean algorithms (Euclidean Mode).

Original Concept & Code: Emilie Gillet (Mutable Instruments). The original Eurorack module source code can be found here.
Disting NT Port: Neal Sanche (GitHub: Thorinside)

The original Grids firmware is licensed under the GPLv3 license, however, as this port utilizes the Disting NT SDK which itself appears to use MIT-licensed components, this port is released under the GNU General Public License v3.0 (GPLv3), consistent with the license used in the nt_grids.cc source file itself.

Features

Two Modes: Switch between classic Drum map interpolation and Euclidean pattern generation.
Three Trigger Outputs: Generate patterns for three independent drum voices (e.g., Kick, Snare, Hat).
Accent Output: Provides an additional accent trigger output common to many Grids patterns.
Clock Input: External clock synchronization.
Reset Input: Resets the sequencer pattern to the beginning.
Chaos: Introduce controlled randomness to patterns (On/Off, with Amount control).
Custom Disting NT UI: Optimized controls for hands-on tweaking using the Disting NT's pots, encoders, and buttons.

Modes

1. Drum Mode

Generates patterns by interpolating through a 2D map of pre-analyzed drum patterns.

Map X / Map Y: Controls the position on the pattern map (0-255). Small changes typically result in related rhythmic variations.
Density 1 / Density 2 / Density 3: Controls the event density (fill) for each of the three main trigger outputs (0-255).
Chaos Amount: Controls the amount of randomness applied (when Chaos is enabled).

2. Euclidean Mode

Generates classic Euclidean rhythms for each of the three main trigger outputs independently.

Length 1 / Length 2 / Length 3: Sets the total number of steps in the sequence for each output (1-16).
Fill 1 / Fill 2 / Fill 3: Sets the number of triggers distributed as evenly as possible within the sequence length for each output (0-Length).
Chaos Amount: Controls the amount of random step-skipping/triggering (when Chaos is enabled).

Inputs

Inputs are configured via the standard Disting NT parameter pages (Routing page).

Clock Input:
- Parameter: Clock Input
- Default: Input 1
- Function: Advances the internal sequencer based on a 24 PPQN (Pulses Per Quarter Note) clock signal. The internal step resolution is tied to this PPQN rate.
- Threshold: > ~0.5V
Reset Input:
- Parameter: Reset Input
- Default: Input 2
- Function: Resets the sequence to the first step on a rising edge.
- Threshold: > ~0.5V

Outputs

Outputs are configured via the standard Disting NT parameter pages (Routing page).

Trig 1 Output / Trig 2 Output / Trig 3 Output / Accent Output:
- Parameter: Trig X Output / Accent Output
- Defaults: Trig 1=Output 3, Trig 2=Output 4, Trig 3=Output 5, Accent=Output 6
- Function: Outputs a trigger/gate signal when an event occurs for that channel.
- Signal: Fixed duration (~5ms), +5V high, 0V low.
- Mode (Trig X Output mode / Accent Output mode):
  - 0 (Add): Adds the trigger voltage to any existing signal on the bus.
  - 1 (Replace): Replaces any existing signal on the bus with the trigger voltage.

Custom UI Mappings

The custom UI provides quick access to the most commonly used parameters for each mode.

Mode Switch: Short press the Right Encoder Button to toggle between Drum Mode and Euclidean Mode.

Drum Mode UI

Pot L: Controls Density 1
Pot C: Controls Density 2
Pot R (Turn Only): Controls Density 3 (with smooth takeover when releasing button)
Pot R (Button Held + Turn): Controls Chaos Amount (smooth takeover applies when releasing button)
Encoder L: Controls Map X
Encoder R: Controls Map Y
Screen:
- Row 1: D1: [val] D2: [val] D3: [val]
- Row 2: X: [val] Y: [val] Chaos: [val/Off]

Euclidean Mode UI

Pots (L, C, R): Control Length 1-3 or Fill 1-3 for their respective channels (Pot L for Ch1, Pot C for Ch2, Pot R for Ch3).
Pot R Button Press: Toggles whether the pots control Lengths or Fills.
Encoder L: No function.
Encoder R: Controls Chaos Amount.
Screen:
- Row 1: L1:[len]:[fill] L2:[len]:[fill] L3:[len]:[fill] (centered). The parameter type currently being controlled by the pots (Length or Fill) is highlighted.
- Row 2: Chaos: [val/Off] (Displayed position matches Drum Mode).

Common UI Elements

Top Center: Displays algorithm title ("Grids", "by Emilie Gillet")
Top Right: Displays plugin version from git tags (e.g., "v1.1.0")

Building from Source

Prerequisites

GNU Arm Embedded Toolchain: Required for compiling for the Disting NT's ARM processor.
- macOS: brew install --cask gcc-arm-embedded
- Other OS: Download from ARM Developer
Faust Compiler: While this specific plugin doesn't use Faust, the Disting NT SDK environment often relies on it being present.
- macOS: brew install faust
- Other OS: See Faust Installation Instructions
Make: Standard build utility.

Build Process

Clone the repository:
```
git clone --recursive https://github.com/thorinside/nt_grids.git
cd nt_grids
```
(Ensure --recursive is used to fetch submodules like distingNT_API)
Compile:
```
make clean
make
```
Output: The compiled plugin object file should be located at plugins/nt_grids.o (verify path based on your Makefile).

Automated Builds

This repository includes a GitHub Actions workflow that automatically builds the nt_grids.o file and packages it into a nt_grids-plugin.zip archive whenever a Git tag starting with v (e.g., v1.0) is pushed. The zip file is attached to the corresponding GitHub Release.

License

This project is licensed under the GNU General Public License v3.0. See the LICENSE.md file for details.

Disclaimer

Documentation written by Gemini 2.5 LLM, and may not be factual.