Mp3 player pcb v1

Overview

We love music, but wanted a way to listen without constantly reaching for a phone and getting distracted. Inspired by the tactile feel of retro physical media, we set out to build a dedicated hardware MP3 player.

This repository contains versioned hardware designs, assembled-board models, and Arduino firmware. The player combines physical transport controls and a rotary volume encoder with a compact OLED interface.

Features

• Standalone MP3 playback through a DFRobot DFPlayer Mini
• 128 × 64 SSD1306 OLED interface
• Previous, play/pause, and next track buttons
• Rotary encoder volume control
• Custom KiCad schematic and two-layer PCB layout
• STEP model of the assembled board

Repository Layout

versions/
├── v1/
│   ├── firmware/
│   │   └── mp3_player_v1/
│   │       └── mp3_player_v1.ino
│   └── hardware/
│       ├── mp3_player_assembly_v1.step
│       ├── mp3_player_pcb_v1.kicad_pcb
│       └── mp3_player_schematic_v1.kicad_sch
└── v2/
    └── README.md

Versioning Convention

Each release keeps its firmware and hardware together under versions/v<release>. Project artifacts follow the descriptive_name_v<release>.<extension> naming pattern.

New iterations should be added as sibling directories rather than overwriting earlier versions. Arduino sketches are kept in matching directories because the Arduino IDE expects a sketch and its containing directory to share a name.

Firmware

Requirements

• Arduino IDE or Arduino CLI
• An Arduino-compatible board configured for the project hardware
• DFRobotDFPlayerMini
• U8g2

SoftwareSerial, SPI, and Wire are supplied by the Arduino platform.

Pin Map

The buttons use the microcontroller's internal pull-up resistors and are active low. Playback actions occur when a button is released.

Upload

1. Install the DFRobotDFPlayerMini and U8g2 libraries with the Arduino Library Manager.
2. Open versions/v1/firmware/mp3_player_v1/mp3_player_v1.ino.
3. Select the correct board and serial port.
4. Compile and upload the sketch.
5. Insert a prepared microSD card into the DFPlayer Mini and power the player.

On startup, the firmware initializes the display, sets the volume to 20, and starts the first track. The current interface labels tracks as trackNNN.mp3 using the file number reported by the DFPlayer.

Current Status

Version 1 includes the complete design sources and an initial working firmware implementation. The firmware currently focuses on core playback, volume control, and a minimal track-number interface; metadata browsing and richer error reporting are not yet implemented.

Version 2 is currently in development. Its directory is reserved, but no hardware or firmware artifacts have been published yet.