lpc40xx_FreeRTOS_MP3_Project

A real-time MP3 player system built on FreeRTOS for the LPC4078F microcontroller. This embedded system integrates file system management, multitasking audio decoding, and interactive user control through a matrix keypad and OLED display—demonstrating complete software and hardware co-design.

To access the project source code, please click here.

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🧠 Features

• Multi-threaded FreeRTOS task design for audio decoding, UI display, and user control
• VS1053 MP3 Decoder integration via SPI and streaming via I2S
• SD card (FAT32) access for audio files using FatFS
• OLED UI (SSD1306) to show current playback status
• Matrix Keypad input for play/pause, track navigation, and volume adjustment
• Clean modular software architecture with separate responsibilities for each layer

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📦 Software Info

• RTOS: FreeRTOS v8.2.0
• Language: C17 (ISO/IEC 9899:2018)
• CPU: LPC4078F (ARM Cortex-M4)
• Build System: SCons v4.1.0
• File System: FatFS with SPI SD card interface
• Key Libraries:
  • OLED Display Driver (I2C, SSD1306)
  • MP3 Decoder Driver (SPI, VS1053)
  • Keypad Matrix Scanning (GPIO)

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🔧 Hardware Info

• SoC Board: SJTwo Board (SJSU Custom Dev Board)
• MP3 Decoder: Adafruit VS1053 Codec v4
  • Datasheet here
• Display: 128×64 OLED using SSD1306
• Input: 4×4 Matrix Keypad
• Audio Output: 3.5mm headphone jack via VS1053 I2S

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🗂️ Software Architecture

The system is broken into several independent FreeRTOS tasks:

• MP3 Playback Task: Streams decoded audio via VS1053
• Display Task: Shows current status (track name, progress)
• User Input Task: Scans matrix keypad for playback control
• File Manager Task: Parses SD card and tracks folder contents

All tasks interact via shared queues and semaphores for thread-safe data exchange.

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🧰 Hardware Design Overview

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🧪 System Assembly

Final prototype includes fully wired system with keypad input, SD-based MP3 loading, and real-time playback.

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🚀 How to Build and Run

1. Clone the repository:

   git clone https://github.com/CMPE146-MP3-PROJECT/FreeRTOS_MP3_Project.git

2. Navigate to the project directory:

   cd projects/lpc40xx_freertos

3. Compile using SCons:

   scons

4. Flash to SJTwo board and connect peripherals (OLED, VS1053, keypad).
5. Insert SD card with MP3 files and enjoy playback.

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👤 Authors

• Zhaoqin Li — Team Lead, System Architecture
• Collaborators: SJSU CMPE146 Spring 2021 Team

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📝 License

This project is released under the MIT License.