midisc
Octatrack 1.40C MIDI scene locks (MIDISC2.0) — rebuild from your own stock OS
About
Highlights
- Scene A and B locks for MIDI tracks, with crossfader morphing
- Works together with step parameter locks and survives Part save and reload
- MIDISC2.0: scenes work before playback starts, scene changes land on the queued pattern or Part boundary, CC values go out before notes, crash fixes
What you need
Your own official OS 1.40C and Python 3. A helper script fetches the stock OS, the build writes MIDISC2.0.bin, which you install from the CF card root with PROJECT > OS UPGRADE.
Good to know
The browser patcher still builds the older 8.2. Never share built files, they contain Elektron's OS. Read the flashing and recovery notes before you start.
README
midisc — MIDISC2.0
ColdFire patch that adds MIDI scene locks to official Octatrack OS 1.40C.
There is no prebuilt firmware in this repo. Rebuild from your own 1.40C.
Browser patcher (still 8.2 until updated):
https://bkkbrls-del.github.io/midisc-patcher/
Changes from 1.40MIDISC8.2
- No first trig needed — scenes / XF work before playback starts.
- Timing — scene changes land at the real queued pattern / Part boundary; manual Part confirm is immediate.
- Active trig locks hold — an unscened lock (including ARP OFF?ON) survives scene/XF refresh until the native lock ends.
- CC before notes — native CC values go out before same-track note-ons.
- Crash fixes — FUNC+REC2 and master-track descriptor repairs; scene scratch kept off native clipboards.
- Pattern-commit Part sync — when the sequencer commits ACT bank/pattern, MIDI scenes follow that pattern's Part immediately (next-step pattern changes included), without waiting for a PLEN cue.
Everything else from 8.2 stays (track-1 lock isolation, unlocked CC path, Part save/reload freeze, etc.).
Build
powershell -ExecutionPolicy Bypass -File scripts/fetch-os.ps1 # or scripts/fetch-os.sh
python tools/build_midisc40.pyWrites MIDISC2.0.bin to your Desktop (splash MIDISC2.0). Flash from CF root ? OS UPGRADE.
The build applies tools/midisc/release20.json to hash-checked stock MAIN. That manifest is the source of truth for this release.
Safety
Modified OS can brick the unit; not affiliated with Elektron; flash at your own risk.
Do not share built .bin files (they contain Elektron’s OS).
Octatrack / Elektron — trademarks of Elektron Music Machines MAV AB.
License
MIT for this repo’s code and docs. Not for Elektron firmware.
Pictures in the README load from GitHub.
- Language
- Python
- License
- Other
- Stars
- 8
- Forks
- 2
- Created
- 09-09-2026
- Last commit
- 3 days ago
- Website
- bkkbrls-del.github.io