JukeboxPanelTwoBoards

A 1970s Jukebox, Reborn for AirPlay

My step-father bought a 1970s-era jukebox that, from what we can tell, spent a number of years in service at a Waffle House. We cleaned it up and gutted its electromechanical guts, original lighting, and speakers, replacing them with an early-90s Sony receiver, 6x9 car speakers, a powered subwoofer, and a Raspberry Pi running the fantastic shairport-sync. The jukebox is now an AirPlay speaker, reachable from any iPhone or Mac on the network.

It looked and sounded great — but the two 7-segment displays and the 12-button keypad were just sitting there dark, begging to be used again. This repo is what's driving them: the same Pi now also runs the original control panel, turning it into a "now playing" display and remote control for a Mac running Music.app.

Play something over AirPlay from another room, and the panel picks it up automatically: a rolling "songs played" counter ticks up on the original 3-digit display, and the jukebox's own numeric keypad lets you punch in a 3-digit code to queue a specific track from a shared playlist — the way the machine worked when it actually took quarters. Two 14-segment alphanumeric displays were added alongside the original panel to show artist, title, and album as they scroll by, since the jukebox never had anything capable of showing that on its own.

How it fits together

 Mac (Music.app) ──AirPlay──▶ shairport-sync ──MQTT──▶ Raspberry Pi ──▶ panel hardware
       ▲                                                    │
       └──────────────── SSH / JavaScript for Automation ◀──┘

• shairport-sync receives the AirPlay stream and publishes track metadata and play/pause/stop events over MQTT.
• The Pi subscribes, drives the physical panel in real time, and turns keypad presses into playback commands — sent back to the Mac either over MQTT or directly via JavaScript for Automation over SSH, whichever proves more reliable at the time.
• A custom PCB and level shifter bridge the panel's original 5V shift-register and keypad-matrix electronics to the Pi's 3.3V GPIO, backed by a small Linux kernel driver that exposes the panel as a character device.

What's in here

Notable bits

• Runs on a read-only root filesystem. The Pi is sandboxed with systemd (ProtectSystem=strict), so config changes happen by editing a file on the Mac, which the Pi fetches at boot — see docs/deployment.md.
• Segment-by-segment reveal animations, not just instant text writes — characters materialize one LED segment at a time on both the alphanumeric and 7-segment displays.
• A real hardware protocol, reverse-engineered and reimplemented: the panel's MM5450/MM5451 shift-register displays and matrix keypad are driven over a shared clock/data bus with no separate keypad wiring — see docs/SPECIFICATION.md for the full wire-level writeup.
• Graceful degradation everywhere: a lost MQTT connection, a Mac that's unreachable at boot, or a corrupt config file each fall back to a safe, visible state instead of crashing.

Credit where it's due

None of this works without shairport-sync, Mike Brady's open-source AirPlay audio receiver. It's what turns the Pi into an AirPlay speaker in the first place, and its built-in MQTT metadata publisher — track info and play/pause/stop events over MQTT — is the signal this entire panel is built to react to. Everything in this repo is downstream of that project.