tabula — plan

tabula is a set of tools around Behringer X32 / Midas M32 consoles, written in Go: a console emulator, and a client that connects to a console (or to the emulator) and serves a web GUI to inspect and drive it, record shows and replay them, and later share them with live viewers.

Binaries

Binary	Role
tabula-emu	Pure console emulator. Speaks the console’s OSC protocol on UDP 10023 so that X32-Edit, M32-Edit, Mixing Station, Maillot’s tools — and the tabula client — can connect to it. Optional read-only HTTP debug page showing the stored state, the traffic and every request it did not understand. It is not a console UI.
tabula	Client. Connects to a console or to tabula-emu over OSC and serves a web GUI on an HTTP port: connection setup, every console menu, recording, replay…

Both share the same library (pkg/).

Library

Package	Content
pkg/osc	OSC 1.0 codec with the console’s leniencies (missing type tags, node replies without a slash).
pkg/schema	The parameter tree: every address, its type, range, steps and how it is written in node/scene text. Built from Maillot’s protocol document and checked against real scene files.
pkg/scene	Scene file (.scn) read/write.
pkg/state	In-memory state store with a change feed; used by the emulator (as the console’s memory) and by the client (as a mirror of the console).
pkg/emu	The emulator’s protocol server and debug HTTP page.
pkg/console	The client side of the protocol: discovery, full sync, /xremote keepalive, meters, rate-limited writes, library commands.
pkg/session	Recording and replay; exports for audio editors.
pkg/audio	Audio capture of the console’s USB card: one WAV file per track, sync with the session.

Milestones

1. Emulator — protocol core (done)

• OSC codec, byte-exact against the document’s examples.
• Schema for every scene node (config, 32 channels, aux ins, FX returns, 16 buses, 6 matrices, main LR/M, DCAs, FX slots, outputs, 128 headamps).
• Scene lines of 3 real scenes round-trip byte for byte (6351 lines).
• State store, scene load/save.
• UDP server: /info, /xinfo, /status, get/set of every parameter, node-address set with multiple type tags, /node, / (echoed), /xremote change fan-out to the other clients (10 s lease).
• Every request not understood is logged (stderr, JSON lines file, debug page) with client, address, type tags and arguments, so connecting X32-Edit/M32-Edit shows what is missing.
• Debug HTTP page: state tree (search), clients, subscriptions, traffic, unhandled requests, current state as .scn.
• Acceptance: a real scene dumped back over the network with /node and with Maillot’s X32GetScene → identical node lines.

2. Emulator — what X32-Edit / M32-Edit need (in progress)

Driven by the unknown-request log while connecting the real editors:

• /-prefs, /-stat, /-show, /-libs, /-action, /-undo, /-usb, /-urec, /-insert, /-ha (1126 nodes; formats checked against a real M32C’s values cached by M32-Edit).
• /meters/0…16 with synthetic levels following the mix, /subscribe, /formatsubscribe, /batchsubscribe, /renew, /unsubscribe.
• Effect parameters (/fx/N/par/NN): fields follow the effect type (switching effect loads its defaults); all 61 effects modelled, with ranges, steps, formats and defaults matching M32-Edit’s built-in tables; 57 of 61 real parameter lines round-trip byte for byte, the other 4 (older firmware spellings) load and are written in today’s form.
• Scenes/snippets/presets library: /save, /load, /copy, /delete, /rename, /add (cues), /showdump, with listings in /-show and /-libs, optionally kept in a directory (-library). Scene safes and snippet filters are not applied yet.
• Side effects of /-action/* (go scene/snippet/cue, clear solo, undo checkpoint and undo, init) and computed status (/-insert, /-ha/NN/index from sources and input routing, /-stat/solo).
• Factory presets: -presets imports M32-Edit’s library (channel, effect and routing presets).
• RTA of the source chosen with /-action/setrtasrc (channels, buses, graphic EQs, pre/post EQ), shaped by low cut, EQ and graphic EQ.
• Linked strips (channels, aux, FX returns, buses, matrices) kept in step, following /config/linkcfg, with the rules of M32-Edit’s offline logic (see docs/emulator.md).
• Connect X32-Edit and M32-Edit, work through the unhandled-request log (guide: docs/testing-with-editors.md).

3. Client — connection and GUI v1 (in progress)

• pkg/console: discovery (broadcast /xinfo), full sync via /node (window of 32 requests), /xremote renewal, writes refused until armed; tested end to end against the emulator.
• Read-only by default on a real console; writes must be armed explicitly.
• Web GUI (React + TypeScript, embedded in the binary): Connect, Mixer (banks, meters, faders, mutes, pans), Channel (config, preamp, gate, dynamics, EQ curve, sends), Browser (every parameter with an editor), Record.
• Server-Sent Events for state changes, status and meters.
• Headamp gain and phantom on the Channel page.
• Routing: input routing and patch, outputs, AES50 A/B, card, P16, aux, AES/EBU, user routing, with names resolved.
• FX pages: overview of the 8 slots, per-slot editor, graphic EQ with the RTA (also behind the channel EQ curve).
• Scenes, snippets and presets: list, recall, save, rename, copy, delete (POST /api/library).
• Linked pairs shown as stereo strips in the mixer.

4. Recording and replay (in progress)

• Session = start snapshot (.scn, opens in M32-Edit) + time-stamped log of every change (who/what/when) + markers (pkg/session).
• Replay to the emulator or a console, with seek and speed; refused unless writes are armed. API in docs/API.md; tabula -record records unattended.
• GUI for recording, markers, session browsing and replay.
• Audio of the console’s USB card recorded with the session, in the same process (pkg/audio): an external recorder (arecord, parecord, ffmpeg or a custom command; no cgo) streams the card, one WAV file per track (24-bit by default, RF64 past 4 GiB, headers refreshed every 2 s), named from the console’s routing; first-sample time and clock drift measured from the arrival of the samples and kept in meta.json; free space watched, clean stop before the disk is full; device listing; -audio-* flags (docs/recording.md).
• Exports for audio editors: Reaper project, Audacity label track, CSV of changes and markers.
• Try the audio capture with the real DN32-USB card (Linux, then macOS/Windows through ffmpeg).

5. Live viewers, roles, band screens (in progress)

• One console connection shared by any number of browsers.
• Roles checked by the server: engineer (this machine, or an engineer link), musician (own in-ear bus only, phone page “In-ears”, works without arming when allowed), viewer (read-only); access links with QR codes on the Access page, kept in access.json, revocable at once (docs/access.md).
• Board-mix audio streaming (WebRTC), setlist, PA calibration.

Protocol notes

• Reference: Unofficial X32/M32 OSC Remote Protocol, P-G. Maillot, updated 2021-06-29 (see docs/README.md).
• Floats are normalized [0, 1] on the wire and quantized to a fixed number of steps (faders 1024, sends 161, EQ frequency 201…).
• Node text is the scene-file format. Numbers round ties away from zero (-8.25 → -8.3); positive levels carry a sign (+0.3), zero does not (0.0).
• Unverified text formats, to check against a real-console /node dump: hold below 10 ms, release below 10 ms or above 999 ms, positive fader levels.

Open decisions

• License: if parameter tables are ported from Maillot’s GPLv3 code, tabula must be GPLv3.