Sidecar 0.2.0

Sidecar 0.2.0

Sidecar 0.2.0: one SD card for the Raspberry Pi 4B and the Raspberry Pi 5, the Pi 5's HDMI display, DSI auto-detect, a faster web page over Wi-Fi and a power warning. It needs the same Rytm build as 0.1.0: rui1027d (or sfx1021 without the remote pages). A MINOR step (semantic versioning): new boards and features, nothing removed.

Sidecar Mini (Teensy 4.1) stays at 0.1.0. 0.2.0 has no Teensy build: Sidecar Mini users keep (or download) sidecar-teensy41-454d38b2.hex and sidecar-mini-plugins-0.1.0.zip from the 0.1.0 release. The Mini works with the same Rytm build.

Part	File
Sidecar (Raspberry Pi 4B and Pi 5, one card)	sidecar-pi-sd-f4b85f8.zip: copy its contents to a FAT32 card; the same card boots both boards. BUILD-INFO-pi.txt names the commit and both kernels
Starter user machines (Pi)	sidecar-pi-plugins-0.2.0.zip: ACID, WAVEPAD, METAL, SNARE, PLUCK, GRAIN as .a64.rmp (MIT), the same files as 0.1.0; they load on the Pi 4B and the Pi 5
Starter content	sidecar-content-0.2.0.zip: /JUNO/Factory/ and /DX7/, the same patches as 0.1.0 (also on the card)
Checksums	SHA256SUMS
Sidecar Mini (Teensy 4.1)	unchanged: the 0.1.0 release's sidecar-teensy41-454d38b2.hex
Rytm mods	unchanged: rui1027d / sfx1021, patched from your own stock OS 1.73 file (PATCHER.md)

New in 0.2.0

• One card for the Pi 4B and the Pi 5 (in testing): config.txt has a [pi4] and a [pi5] section and each board reads only its own boot files (Pi 4: sdboot.img and engine.img as in 0.1.0; Pi 5: kernel_2712.img). The Pi 4 boots with exactly the 0.1.0 settings. The Pi 5 build itself is tested on hardware; the shared card is being tested on both boards now.
• Raspberry Pi 5 (tested on hardware) (2026-10-19): the Rytm over USB (replug included), the voices and send effects, the remote pages, sidecar.local over Ethernet and Wi-Fi. The Pi 5 is a standalone Sidecar for now: its USB-C port is power only (no USB audio or MIDI to the computer).
• Pi 5 HDMI display (tested on hardware): the 800x480 UI scaled to the Pi 5 firmware's 1920x1080 picture, with USB touch. hdmi_force_hotplug=1 (on the card) is needed; connect the display to micro-HDMI 0 before power-on. The picture is slightly soft (scaled).
• DSI displays found by themselves (in testing): the official 7" display v1 and compatibles, on the Pi 4 through the firmware (as in 0.1.0) and on the Pi 5 driven by the engine (CAM/DISP 0 or 1, no config.txt line). With no DSI panel answering, the Sidecar uses HDMI. Not yet run on hardware.
• The web page over Wi-Fi (in testing): the page is sent compressed (121 KB to 39 KB), a stalled connection is dropped after 3 s (was 5 s), the page sends at most 2 requests at once and retries a "503 busy". /status and the log count the connections.
• Power warning (in testing): the Pi reads its supply's state (under-voltage, throttling; on the Pi 5 also the USB-PD current) at boot, on a change and once a minute: in the log, on the web page's Power tile with a warning, and in red on the display's bottom line. The warning names the board's official supply: on a Pi 4 "use the official 15 W (5.1 V 3 A) supply" (display POWER TOO WEAK: use 15 W supply), on a Pi 5 "use the 27 W (5 V 5 A) adapter directly" (POWER TOO WEAK: use 27 W adapter).
• Wi-Fi firmware for both boards on the card (/firmware/, the same Raspberry Pi files under each board's names, with the Cypress licence). Still no Wi-Fi settings on the card: Wi-Fi is off until you set it up.

Hardware: Pi 4B or Pi 5

	Raspberry Pi 4B	Raspberry Pi 5
Use	with a computer: also the Sidecar's USB-C audio and MIDI interface	standalone: no USB audio or MIDI to the computer yet
Supply	official 5.1 V 3 A USB-C	official 27 W USB-C, plugged in directly (not through a hub)
HDMI display	800x480, sharp	the UI scaled to 1920x1080: works, slightly soft
DSI display	expected (firmware), being confirmed	in testing
Wi-Fi	works	works (tested)
Kernel update	card swap (or sdboot.py with sdport on)	card swap only

Known issues in 0.2.0

• Pi 5: no USB audio or MIDI to the computer. Its USB-C gadget is left out of this build: even Raspberry Pi OS's own USB gadget did not connect on our Pi 5 powered from a computer. Use a Pi 4B for computer audio.
• Pi 5: use the official 27 W supply directly. Fed from a hub port the Pi 5 ran in reduced-power mode, and Wi-Fi and the web page became slow (pages of 5 s, "503 busy"). The power warning says so when it sees it.
• Pi 5 HDMI: the firmware always sets 1920x1080, so the 800x480 UI is scaled (slightly soft). The framebuffer_width, framebuffer_height and hdmi_* mode lines under [pi5] do nothing on the Pi 5 and are harmless; only hdmi_force_hotplug=1 matters.
• Pi 5 DSI has not been run on hardware yet; Touch Display 2 is not supported on either board.
• Pi 5 updates are by card swap only (no network update on the Pi 5 yet). If a Pi 5 shows its boot diagnostics screen, update its bootloader with Raspberry Pi Imager.

Everything from the 0.1.0 known issues still applies: see KNOWN-ISSUES.md.

Install: INSTALL-PI.md or https://trigcondition.github.io/sidecar-expander/getting-started/install-pi/. Check the downloads with shasum -a 256 -c SHA256SUMS.

Sidecar 0.1.0

Sidecar 0.1.0: the first public tester release of Sidecar | Expander, a voice and feature expander for the Analog Rytm MKII. A small computer on the Rytm's USB port, Sidecar Mini (Teensy 4.1) or the full Sidecar (Raspberry Pi 4B), plus a set of mods to the Rytm's OS 1.73: digital voices on the Rytm's own tracks, two extra send effects, LFOs, recording, computer audio, and the Sidecar's own pages on the Rytm's screen.

Documentation, the browser patcher and the Sidecar Mini console: https://trigcondition.github.io/sidecar-expander/

What you need

• An Analog Rytm MKII on OS 1.73 and the stock Analog-Rytm_MKII_OS1.73.syx from the official download page (we do not distribute firmware). On OS 1.74, flash the stock 1.73 file first. OS 1.74 will be supported after testing.
• A Teensy 4.1 (Sidecar Mini; solder its USB host header) or a Raspberry Pi 4B (Sidecar, 2 GB or more).
• On the Rytm: USB CONFIG set to the Overbridge mode.

Install

1. Patch your own stock OS file in the browser: https://trigcondition.github.io/sidecar-expander/patcher/ . Pick rui1027d (default: the mods plus the remote pages) or sfx1021 (without the remote pages). The patcher checks the result against our build (rui1027d sha256 4843848805c0e08b3cf7c69bf5b68ca7e1453bb643d351709bdad9f59468dce8). Send it to the Rytm with Transfer.
2. Sidecar Mini: load sidecar-teensy41-454d38b2.hex with the Teensy Loader; install user machines from sidecar-mini-plugins-0.1.0.zip in the web console.
   Sidecar (Pi 4B): extract sidecar-pi4-sd-454d38b2.zip to a FAT32 card (it includes the starter content); user machines from sidecar-pi-plugins-0.1.0.zip.
3. Starter content: extract sidecar-content-0.1.0.zip to the root of the Sidecar's card (Juno-106 factory patches and DX7 banks).

Install guides: Sidecar Mini, Sidecar.

What's in 0.1.0

• EXT machines PLAITS, DAISYSP, DIGIDRUM, JUNO, 6-OP FM, DSP SAMPLE (with GRAIN) on every track, five user-machine slots and six starter machines.
• SEND FX 1/2: CHORUS, COMB, CRUSH, RINGMOD and the new HALO plate on both Sidecars; RINGS, CLOUD SEED, STUTTER on the Pi.
• Remote pages in the Rytm's own font: connect screen, SIDECAR / SYSTEM status, SCOPE and meters, the REC page (playback on the Pi), the LFO page; the SRC view shows the Sidecar machine's page on the Rytm's own SRC page.
• Recording: the Pi's 23-source recorder with playback, the Mini's stereo recorder, the Rytm's FX return on IN L/R.
• Computer audio: multi-channel with MIDI on the Pi, stereo with MIDI on the Mini.
• LFOs (8 on the Pi, 4 on the Mini, per kit; in testing), the Pi's web page and touch display.
• Full notes: https://trigcondition.github.io/sidecar-expander/release-notes/ and what is tested on hardware: https://trigcondition.github.io/sidecar-expander/introduction/what-works-now/

Known issues

• In testing: LFOs per kit, PSRAM on the Mini, the Pi's Wi-Fi page and sidecar-wifi.txt first setup.
• The Mini's multichannel USB audio is not in this release; the Mini's USB audio pauses while its recorder runs (without PSRAM).
• Wait for the connect screen before pressing PLAY. After many replugs the Pi may need a restart ("Cannot set device address").
• More: https://github.com/trigcondition/sidecar-expander/blob/main/KNOWN-ISSUES.md

Source code

The source is public: sidecar-firmware (the engine for Sidecar Mini and Sidecar, the code of this release) and sidecar-mods (the Rytm mods; it rebuilds rui1027d byte for byte from your own stock OS file). Contributions go through pull requests. For at least three years we will give anyone who asks the complete corresponding source for the GPL parts: the Raspberry Pi engine (engine.img, sdboot.img, including Circle, GPLv3), the Rytm mods in the patch files (including the elekloader core, GPL-2.0-or-later), and the Teensy firmware (with what is needed to relink its LGPL-2.1 parts). Open an issue titled "Source request". Licences: LICENSE, THIRD_PARTY_LICENSES.

Checksums

See SHA256SUMS in the assets.

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Unofficial, experimental software, not made, endorsed or supported by Elektron. "Analog Rytm" and "Overbridge" are their trademarks, used only to say what this works with. Back up your projects before you flash; flashing the stock OS takes you back.