eastlight 0.2.0

Open-source editor/librarian for the Roland RC-505 MK2 loop station

EastLight

Open-source editor/librarian for the Roland RC-505 MK2 loop station — CLI and GUI.

EastLight reads and writes the RC-505 MK2's SD card backup format (ROLAND/ directory), giving you full control over memory patches, audio tracks, effects, and system settings from the terminal or from a graphical interface.

v0.2.0 — Alpha release. The file format parser achieves byte-for-byte round-trip fidelity and ~98% schema coverage. Back up your SD card before using EastLight on real data.

Install

From PyPI (recommended)

pip install eastlight

For the graphical interface (PyQt6):

pip install eastlight[gui]

From source

git clone https://github.com/liotier/EastLightRC-505mk2Librarian.git
cd EastLightRC-505mk2Librarian
pip install -e ".[gui]"

Requirements

• Python 3.11+
• libsndfile — required by the soundfile dependency for audio I/O

libsndfile is bundled automatically on Windows and macOS. On Linux, install it with your package manager:

# Debian / Ubuntu
sudo apt install libsndfile1

# Fedora
sudo dnf install libsndfile

# Arch
sudo pacman -S libsndfile

Verify installation

eastlight --version
eastlight --help

Graphical interface

Launch the GUI with:

eastlight gui

Or point it at a specific ROLAND/ directory:

eastlight gui -d /media/user/RC505/ROLAND

The GUI provides:

• Memory list — browse all 99 slots with name, track count, and tempo
• Parameter editor — tabbed, schema-driven editors for every section (tracks, master, FX, mixer, routing, EQ, etc.)
• System settings — edit SETUP, PREF, MIDI, USB, INPUT, and COLOR settings
• WAV import/export — import audio files, export tracks
• Undo/redo — full undo stack for parameter edits
• Device detection — auto-detect connected RC-505 MK2 devices

Requires pip install eastlight[gui] (adds PyQt6).

Getting started (CLI)

1. Connect your RC-505 MK2

Connect via USB and mount the SD card (the device appears as a USB mass storage device), then point EastLight at the ROLAND/ directory:

eastlight detect
eastlight config --set-dir /media/user/RC505/ROLAND

Once a default directory is set, all commands use it automatically. Override anytime with -d /path/to/ROLAND.

2. Browse and inspect memories

eastlight list                        # All 99 memory slots
eastlight show 1                      # Full details for memory 1
eastlight show 1 -s TRACK1            # Just track 1 parameters
eastlight show 1 --raw                # Raw field values

3. Edit parameters

eastlight set 1 MASTER pan 75
eastlight name 1 "My Loop"
eastlight set 1 TRACK1 play_level 100 --dry-run   # Preview without writing

All write commands support --dry-run / -n to preview changes safely.

Command reference

Memory management

Command	Description
eastlight list	List all 99 memory slots with names, tracks, tempo
eastlight show <mem>	Show parameters for a memory (-s SECTION to filter)
eastlight set <mem> <section> <param> <value>	Set a parameter value
eastlight name <mem> <name>	Rename a memory slot (max 12 characters)
eastlight copy <src> <dst>	Copy a memory slot (RC0 + WAV audio)
eastlight swap <a> <b>	Swap two memory slots
eastlight clear <mem>	Clear a memory slot (with automatic backup)
eastlight diff <a> <b>	Show differences between two memories

Batch operations

Command	Description
eastlight bulk-set <range> <section> <param> <value>	Set a parameter across multiple memories
eastlight template-export <mem> <file>	Export a memory's parameters as YAML
eastlight template-apply <file> <range>	Apply a YAML template to one or more memories

Memory ranges support commas and dashes: 1-5, 1,3,5, 1-3,7,10-12.

eastlight bulk-set 1-10 MASTER play_level 100
eastlight template-export 1 my_settings.yaml
eastlight template-export 1 fx_only.yaml -s TRACK1 -s MASTER
eastlight template-apply my_settings.yaml 5
eastlight template-apply settings.yaml 1-10 --dry-run

Audio import/export

Command	Description
eastlight wav-info <mem>	Show WAV audio info for all tracks
eastlight wav-export <mem> <track> <file>	Export a track's audio
eastlight wav-import <mem> <track> <file>	Import an audio file into a track

eastlight wav-export 1 1 my_loop.wav
eastlight wav-export 1 1 my_loop.wav --format pcm24
eastlight wav-import 1 2 recording.wav

Supported import formats: WAV, FLAC, OGG (anything libsndfile supports). Audio is automatically converted to 32-bit float stereo at 44.1 kHz (the device's native format). Mono files are duplicated to stereo.

Effects

Command	Description
eastlight fx-show <mem> <ifx|tfx>	Show FX chain parameters
eastlight fx-set <mem> <ifx|tfx> <slot> <param> <value>	Set an FX parameter

eastlight fx-show 1 ifx                       # All input FX
eastlight fx-show 1 tfx -g A                  # Track FX group A
eastlight fx-show 1 ifx -s AA                 # Specific slot
eastlight fx-set 1 ifx AA feedback 30
eastlight fx-set 1 ifx AA fx_type 35 --dry-run

70 effect types fully mapped: filters, modulation, delay, reverb, dynamics, pitch, vocoder, slicer, and 4 TFX-exclusive beat effects.

System settings

Command	Description
eastlight sys-show	Show system settings (-s SECTION to filter, --all for everything)
eastlight sys-set <section> <param> <value>	Set a system parameter

eastlight sys-show -s SETUP
eastlight sys-set SETUP contrast 8
eastlight sys-set PREF pref_eq 0 --dry-run

MIDI controller assignments

Command	Description
eastlight ctl-show	Show controller assignments (--type ictl or --type ectl)
eastlight ctl-set <instance> <param> <value>	Set a controller assignment

eastlight ctl-show --type ectl
eastlight ctl-set ICTL1_TRACK1_FX ctl_func 42
eastlight ctl-set ECTL_CTL1 ctl_func 10
eastlight ctl-set ECTL_EXP1 ctl_range 64

Internal controllers (ICTL): 47 panel button and pedal assignments across 3 banks. External controllers (ECTL): 6 MIDI CC inputs (CTL1-4, EXP1-2). All 201 CTL FUNC values are mapped to human-readable names with push/hold/click sub-actions.

Backup management

Command	Description
eastlight backup list	List all automatic backups
eastlight backup show <timestamp>	Show backup details
eastlight backup restore <timestamp>	Restore a backup
eastlight backup prune --keep <n>	Remove old backups

EastLight automatically backs up files before any write operation. Backups are timestamped and stored in ~/.config/eastlight/backups/ (outside the device filesystem).

Configuration

Command	Description
eastlight config --show	Show current configuration
eastlight config --set-dir <path>	Set default ROLAND/ directory
eastlight config --no-backup	Disable automatic backups
eastlight detect	Auto-detect connected RC-505 MK2 devices

Configuration is stored in ~/.config/eastlight/config.yaml.

ROLAND/ directory resolution order:

1. Explicit -d/--dir option
2. Default from eastlight config --set-dir
3. Single auto-detected device (USB mount scan)

Utility

Command	Description
eastlight parse <file>	Parse and display raw structure of an RC0 file
eastlight --version	Show version
eastlight --help	Show help

Safety

All write commands create an automatic backup before modifying any files. Use --dry-run to preview changes first.

eastlight set 1 MASTER pan 75 --dry-run
eastlight clear 5 -n
eastlight bulk-set 1-10 MASTER play_level 100 -n

To disable automatic backups: eastlight config --no-backup

Schema coverage

~98% of the RC-505 MK2's file format is mapped:

• All memory-level sections (track, master, EQ, mixer, routing, assign, ...)
• All 70 FX effect types (66 shared + 4 TFX-exclusive)
• FX type index enum with reverse lookup
• System settings (SETUP, PREF, COLOR, USB, MIDI)
• All 53 ICTL + 6 ECTL controller mapping sections
• All 201 CTL FUNC values (0-200) with push/hold/click sub-actions

Remaining gaps: 13 SETUP fields (J-V), 6 PREF fields (O-T), 4 CTL FUNC preferences (MODE PLAY, MODE UNDO, QUICK CLEAR, ALL CLEAR), 3 INPUT preferences (MIC/INST1/INST2 SYSTEM/MEMORY toggle). See the feasibility study for details.

Development

git clone https://github.com/liotier/EastLightRC-505mk2Librarian.git
cd EastLightRC-505mk2Librarian
pip install -e ".[dev]"
pytest

License

GPL-3.0-or-later