RIFT for the M-VAVE FM-1

Experimental drone firmware, heavily inspired by the dystopian sounds of the VHIKK-X, by FORGE TME. This firwmare is a built on a modified version of Felucca.

Nine original modes combine oscillator pairs and clusters, phase/ring modulation, filtering, stereo delay/scattering feedback and frequency translation.

Deep, warm, atmospheric drones, with room to push into stranger and more abrasive textures.

Sound and controls

Modes: PAIR, FOLD, SINES, WAVES, CHORD, CLUSTER, PARTIAL, CROSS and CAVERN. RIFT occupies part 1 and owns the stereo output while active. Felucca supplies hardware support, USB MIDI/audio, storage, the updater and recovery entry.

SELECT sets root pitch, ALGORITHM chooses a mode, PRESETS recalls one of three sounds per mode. ENV/EDIT, FX and LFO select the three macro pages; K1–K4 edit the active page. ARP toggles drone/keyed operation; REC varies SEED/SCAN; the master volume pot keeps its usual function. See the RIFT guide for every control, MIDI CC, implementation detail and known limit, and the reference research for the documented inspiration.

Get the source and run host tests

git clone --recurse-submodules https://github.com/mykeln/fm1-rift.git
cd fm1-rift
python3 -m venv .venv
.venv/bin/python -m pip install -r requirements.txt
sh rift.sh test

Host tests need a C compiler and Python 3. They generate headers, run RIFT integration tests under AddressSanitizer/UndefinedBehaviorSanitizer, and render nine short stereo WAV previews and screen captures into firmware/build/rift-demo/. CI also checks the installer against simulated hardware. The palette checks also render all 27 sounds and measure every dial in every mode. The unnormalized listening previews are in firmware/build/audio-palette/ and, after a build, dist/audio/palette/. Host tests do not establish subjective sound quality or real-device performance.

For an existing clone, run git submodule update --init --recursive. The engine and board-support dependencies are pinned. GitHub's automatic source ZIP/tar downloads omit those dependencies; use a recursive Git clone.

Preview and build

sh rift.sh preview    # desktop simulator; requires SDL2
sh rift.sh build      # FM-1 build and local review bundle; requires JieLi tools/SDK

Install SDL2 with brew install sdl2 on macOS or libsdl2-dev on Debian/Ubuntu. The simulator uses its own flash file and starts with MIDI disabled.

For the FM-1 build, follow firmware/BUILDING.md for the JieLi compiler, pinned AC79 SDK and Docker prerequisites. Run commands from firmware/ when following that upstream guide. RIFT's wrapper respects PYTHON, JIELI_TOOLCHAIN, AC79_SDK and DOCKER_CONTEXT. Without local overrides, the underlying build uses ~/.jieli/toolchain and ~/fw-AC79_AIoT_SDK; Linux x86-64 runs the toolchain natively.

The original local setup keeps tools in .tools/ and uses a Colima profile/context named fm1-build / colima-fm1-build on macOS. Those tools, the SDK, build products and .venv/ are excluded from Git. They are not required for host tests. Start that VM with colima start --profile fm1-build if you use that setup.

The local bundle is written to dist/. RIFT 0.6 uses local update identity FM-1_906, distinct from 0.5's FM-1_905, 0.4's FM-1_904, 0.3's FM-1_903, 0.2's FM-1_902 and 0.1's FM-1_900. firmware/firmware/src/rift_update_id.h supplies the identity to both the package and running firmware; increase its revision for each installable update, because M-UPGRADE compares it rather than the displayed version or filename. A registered identity namespace and real-device validation are required before a public installable release. Do not use Felucca's --release version numbering to publish RIFT packages: it assigns Felucca identities.

Hardware validation and publication

Read the hardware trial and rollback guide before considering installation. Installing may replace incompatible stored data. RIFT reuses Felucca's project formats, but cross-firmware project/sample compatibility and persistence have not been verified on hardware. Preserve your data and establish a recovery route first.

Publication tracking records directory submissions and the remaining release checks. Directory research links each maintainer's submission requirements. The Firmware Hub requires install/exit tests on a real device before listing; this project currently belongs in experimental source listings.

Contributing and licenses

Contributions and bug reports are welcome. The modified Felucca source is under firmware/; upstream Git history is retained. RIFT is based on Felucca commit 743551712c36b3984392eea1dbe13a309907e17a.

RIFT is GPL-3.0-only; dependencies retain their own licenses. See LICENSE, LICENSING.md, upstream credits and component notices. No VHIKK-X firmware, code or wavetable assets were used. No affiliation with M-VAVE or FORGE TME is implied.