Nord Modular G2 - Editor

For all non tech documentation see: https://janburp.github.io/NordModularG2-Editor/

What follows is a brief technical overview and how to setup a local development.

Tech stack

• An editor for the Nord Modular G2 for multiple platforms (macOS, Windows and later Linux)
• Using tech that is widely available and used by many developers.

This editor is build with electronjs, with TypeScript and VueJS. It uses a C CLI/Daemon to handle the USB communication. Which will be part of the build.

CLI/Daemon in C

The CLI/Daemon handles all USB communication with the G2 hardware. All responses from the G2 goes to stdout in JSON format. All commands are send to the Daemon (or CLI) via stdin.

This CLI / Daemon approach makes it possible to use the CLI/Daemon on it's own, or to be used in a different editor. There are commands for connecting, transfering patches, editing patches, editing settings etc.

ElectronJS

ElectronJS is used for the actual editor. It can run in an offline mode without the daemon (so without connected G2) to edit only files. In the default online mode it communicates with the G2 through the daemon.

Structure

• cli/ — C CLI tool for USB communication with the G2 hardware
• g2-editor/ — Electron desktop app (Vue 3 + TypeScript)

Documentation

• USB Protocol — USB framing, commands, watch events, daemon architecture
• Patch File Format — PCH2/PRF2 binary format, sections, bit encoding

Prerequisites

• macOS: brew install libusb
• Windows: handled via the release build script (MinGW cross-compile)

Build

CLI

cd cli
make                    # build cli
make test               # run all tests
make test-unit          # run unit tests (no need for connected G2)
make test-integration   # run integrations tests (needs connected G2)

Electron app

cd g2-editor
npm install
cd ../cli && make && cd ../g2-editor   # rebuild CLI first
npm run postinstall                     # copies CLI binary into app resources
npm run dev                             # development server

CLI Commands

Connection

Command	Arguments	Description
connect		Connect to G2
disconnect		Close connection
startup		Full startup (init + device + all slots + names)
device		Show device info
list-devices		List USB devices (debug)

Patches & Performances

Command	Arguments	Description
get-patch	<slot>	Get patch from slot as JSON
get-patch-file	<slot> [file]	Save patch as .pch2 file
get-perf-file	[file]	Save current performance as .prf2 file
upload-patch	<slot> <filepath>	Upload .pch2 to slot
upload-perf	<filepath>	Upload .prf2 performance
select-patch	<slot> <bank> <loc>	Load bank patch into slot (bank 1–32, loc 1–127)
select-perf	<bank> <loc>	Load bank performance
list	[type] [bank <n>]	List patches/performances (optionally filter by type or bank)
get-perf-settings		Get current performance settings
set-perf-mode	<patch|performance>	Switch between patch and performance mode
set-perf-name	<name>	Set performance name
set-patch-name	<slot> <name>	Set patch name
set-patch-description	<slot> <hexdata>	Set patch description (hex-encoded)
set-synth-settings	<json>	Set all synth settings from JSON

Slots

Command	Arguments	Description
slot	<A|B|C|D>	Change active slot
variation	<1–8> [slot]	Select variation for slot
set-slot-enabled	<slot> <0|1>	Enable/disable a slot
set-slot-key	<slot> <0|1>	Assign/unassign keyboard to slot
set-slot-hold	<slot> <0|1>	Set slot hold mode
set-slot-range	<slot> <lower> <upper>	Set note range for slot (0–127)
set-range-enable	<0|1>	Enable/disable slot range

Voice

Command	Arguments	Description
voice-mode	<slot> <0–3>	Set voice mode (0=poly 1=mono 2=legato 3=slgt)
voice-count	<slot> <1–32>	Set voice count

Clock

Command	Arguments	Description
set-master-clock-run	<0|1>	Start/stop master clock
set-master-clock-bpm	<30–240>	Set master clock BPM

Modules

Command	Arguments	Description
add-module	<slot> <va|fx> <type-id> <module-id> <col> <row> <color> <num-modes> [modes] <num-params> [params] <name>	Add module to patch
del-module	<slot> <va|fx> <module-id>	Delete module (delete cables first)
move-module	<slot> <va|fx> <module-id> <col> <row>	Move module to grid position
set-module-color	<slot> <va|fx> <module-id> <color:0–24>	Set module color
set-module-name	<slot> <va|fx> <module-id> <name>	Set module label
set-module-mode	<slot> <va|fx> <module-id> <param-idx> <value>	Set module mode parameter

Cables

Command	Arguments	Description
add-cable	<slot> <va|fx> <color:0–6> <from-mod> <0|1> <from-con> <to-mod> <0|1> <to-con>	Add cable between jacks
del-cable	<slot> <va|fx> <from-mod> <0|1> <from-con> <to-mod> <0|1> <to-con>	Delete cable
set-cable-color	<slot> <va|fx> <color:0–6> <from-mod> <0|1> <from-con> <to-mod> <0|1> <to-con>	Set cable color

Parameters

Command	Arguments	Description
set-param	<slot> <va|fx|patch> <module-id> <param-idx> <value> <variation>	Set module parameter value
set-param-label	<slot> <va|fx> <module-id> <param-idx> <label-idx> <label>	Set parameter label

Resources & Daemon

Command	Arguments	Description
get-resources	<slot>	Get CPU/memory resource usage
daemon		Persistent: watch events + accept JSON commands on stdin
seq	"<cmd1>" "<cmd2>" ...	Run multiple commands sequentially

Monitoring

g2-cli watch                            # monitor G2 messages
g2-cli daemon                           # persistent connection: watch (stout) + commands on stdin

Daemon

Recommended: tmux dev environment

For interactive daemon use, use the tmux launcher (needs tmux installed on your machine):

cd cli
./g2tmux.sh

This opens a split-pane tmux session:

• Left pane: daemon output (watch events, responses)
• Right pane: command shell with autocomplete

Type commands directly (no prefix needed), some examples:

slot A                                  # switch focus to slot A
get-patch A                             # read patch from slot A
variation 4 B                           # select variation 4 on slot B
verbose off                             # suppress LED/volume updates
set-perf-mode patch                     # switch to patch mode
stop                                    # kill daemon
start                                   # restart daemon

Note: Type command name + TAB to autocomplete (commands only, system commands suppressed). Arguments also autocomplete: get-patch <TAB> → A B C D.

Manual daemon mode (if not using tmux):

# Terminal 1 — start daemon, reading commands from a named pipe
mkfifo /tmp/g2-cmd
./build/bin/g2-cli daemon < /tmp/g2-cmd

# Terminal 2 — keep the pipe open and send commands like this:
exec 3>/tmp/g2-cmd
echo '{"id":1,"cmd":"slot","args":["B"]}' >&3               # Change slot B
echo '{"id":2,"cmd":"variation","args":["4","B"]}' >&3      # Change to variation 4 on slot B
echo '{"id":3,"cmd":"device"}' >&3                          # device info
echo '{"id":5,"cmd":"verbose","args":["off"]}' >&3          # suppress LED/volume
exec 3>&-   # close when done (causes daemon to exit cleanly)

The exec 3>/tmp/g2-cmd keeps the write end open so each echo doesn't trigger EOF.