Assembly
Parts & wiring
The full parts list for the breadboard path, plus the GPIO pinout verified in the firmware.
Parts list
BOM, breadboard version
Everything needed for path A. Indicative 2026 prices, shipping excluded.
| Component | Suggested reference | Qty | Ind. price |
|---|---|---|---|
| ESP32-S3 N8R8 | ESP32-S3-DevKitC-1 N8R8 | 1 | ~€12 |
| NFC reader | PN532 module (SPI mode) | 1 | ~€6 |
| I2S audio amplifier | MAX98357A | 1 | ~€5 |
| Speaker | 4 Ω 3 W (40-50 mm) | 1 | ~€3 |
| microSD reader | SPI breakout module 3.3 V | 1 | ~€2 |
| microSD card | Class 10 / U1, 8-32 GB, FAT32 | 1 | ~€6 |
| RGB LED strip | WS2812B, 8 LEDs | 1 | ~€3 |
| Rotary encoder | EC11 type with push button | 1 | ~€1 |
| Push buttons | Momentary buttons | 4 | ~€1 |
| NFC tags | NTAG213/215/216 (Type 2) | ≥5 | ~€5 |
| Breadboard + wires | Breadboard + Dupont wires | 1 set | ~€6 |
| LED capacitor | Electrolytic 100-1000 µF | 1 | ~€0.20 |
| USB power supply | USB 5 V brick (1 A min.) + cable | 1 | ~€5 |
The firmware uses no screen. For a portable build, a LiPo Rider module (planned for the 3D-printed enclosure, still being designed) powers the MusicBox from a LiPo battery. In-firmware battery management is still to come.
Wiring
Connecting the components
GPIO pinout per peripheral, verified against the firmware code. Logic levels at 3.3 V.
| Peripheral | Bus | Pins (GPIO) |
|---|---|---|
| PN532 NFC | SPI | SCK 14 · MOSI 13 · MISO 12 · SS 15 · RST 3 |
| microSD card | SPI | SCK 18 · MOSI 17 · MISO 8 · CS 5 |
| MAX98357A audio | I2S | DIN 40 · BCLK 41 · LRC 42 |
| WS2812B LED strip (×8) | RMT | DATA 16 |
| EC11 encoder | PCNT | CLK 9 · DT 11 · SW 10 |
| Action buttons ×4 | GPIO | 45 · 46 · 47 · 48 (active LOW) |