rPod

A Raspberry Pi Zero 2 W music player built around an original 4th-gen iPod click wheel, a 2" ST7789V LCD, and an I²S DAC for bit-perfect lossless playback via MPD.

Full spec, hardware BOM, GPIO map, and phased build plan: docs/PLAN.md.

Status

Phase 1 (display) — done and hardware-verified: landscape 320×240 via fbtft's rotate=90, LVGL rendering and animating at a measured 30 fps.

Phase 2 (click wheel) — daemon/rpod-wheel.c and tools/wheel-test-client are written and build clean, but the click wheel's real bit map has not been derived on hardware yet: daemon/wheel_bits.h intentionally fails to build until tools/wheel-sniff.c has been run on the actual wheel and docs/clickwheel-protocol.md filled in (docs/PLAN.md §4.3). The physical wheel is currently dead, so this step is blocked until a replacement is sourced.

Phase 3 (audio) — not started; the DAC isn't wired up yet.

UI (pulled forward from Phase 4, ahead of hardware) — the full §8.1 screen graph (Main Menu, Music browse/playback, Now Playing, Settings, Extras) is built and runs in the desktop simulator against a real local MPD instance (make mpd-dev, then make sim). Since there's no working click wheel to test against, tools/sim/sim_input.c stands in with the keyboard: Left/Right arrows rotate, Enter selects, M/Space/N/P are Menu/ Play-Pause/Next/Prev (Menu is M, not Escape — see tools/sim/sim_input.c for why Escape collides with the encoder's own key handling). src/main.c (the on-device binary) is untouched — wiring the real wheel socket into these same screens has to wait for working wheel hardware. See docs/PLAN.md §9 for the phase list and acceptance criteria.

Building

# Desktop UI simulator (no hardware needed)
make sim

# Cross-compile for the Pi
make build

# Deploy + run on hardware (rpod.local)
make deploy-run

Layout

• src/ — on-device application (UI, audio client, library index, power).
• daemon/ — rpod-wheel, the privileged click wheel decoder, and the wheel_protocol.h/wheel_bits.h headers shared with its clients.
• system/ — boot config fragments, systemd units, udev rules, USB gadget setup.
• tools/ — wheel-sniff (protocol analysis), wheel-test-client (prints normalised wheel events), fb-test (raw framebuffer colour/orientation check), and sim/ (desktop UI harness).
• third_party/ — vendored LVGL.

License

Click wheel decoding derives from dupontgu/retro-ipod-spotify-client (Apache-2.0) — see docs/PLAN.md §12. LVGL is MIT.