AKOR 01

AKOR_01

AKOR_01 is a compact hardware controller for playing notes, chords, and simple sequences.

These renders show the current NO_LED PCB revision: the RGB subsystem is absent, the matrix and encoder controls are routed, and the diode matrix is on the solder side.

The confirmed V0 interface contains a 4 × 5 performance grid plus Shift (21 MX switches total), seven push encoders, and an OLED display.

Architecture locked on 2026-07-31

V0 is an independent USB-MIDI controller based on Raspberry Pi Pico 2 H.

A future standalone synthesizer is a separate V2 project. V2 is intentionally not a compatibility constraint for the V0 PCB.

V0 hardware target

• Raspberry Pi Pico 2 H as the USB-MIDI device and control processor;
• 21 MX-compatible switches and 21 × 1N4148 in a scanned matrix;
• 7 bare EC11-style encoders with integrated push switches;
• 1 × MCP23017 I²C GPIO expander;
• 1 × SSD1306-compatible I²C OLED module;
• no onboard audio or DSP output stage.

The intended signal allocation is:

• encoder A/B: 14 direct Pico GPIO inputs;
• one encoder push switch: one direct Pico GPIO input;
• matrix rows/columns plus six encoder push switches: one MCP23017;
• OLED and MCP23017: shared 3.3 V I²C bus;
• USB: Pico 2 H onboard micro-USB, carrying power and class-compliant MIDI.

Software state

The existing C++ prototype can:

• generate sine, square, triangle, and sawtooth waveforms;
• convert MIDI note numbers into frequencies;
• map a 16-key input across a chromatic octave range;
• apply an ADSR-style envelope;
• write mono 16-bit, 48 kHz WAV output.

That offline audio work is preserved for the separate V2. The V0 software goal is musical-state handling, control scanning, OLED feedback, and USB MIDI Note On/Off/Panic.

Fabrication status

The NO_LED PCB layout has completed its routing and DRC checkpoint. It still requires a mechanical review and Gerber/NC Drill inspection before any fabrication order.

Repository state (2026-08-08)

• main is the single build source: NO_LED V0 PCB (incl. MIDI DIN-5) + firmware.
• The RGB LED add-on work (SK6812MINI-E chain, 74AHCT1G125 buffer, associated SMD passives) is archived, not part of V0: see branch archive/rgb-led (commandes RGB, préservée). archive/no-led-old preserves the pre-DIN5 NO_LED branch (also deleted).
• hardware/BOM_AKOR_01.csv = buying/assembly list exported from Notion Composants AKOR_01, scoped to the NO_LED build only.