This mp3 player project is built based on Arduino Mega. It is equipped with STA013S MP3 decoder, an SD card for storage, and a nokia LCD for display. When it is turned on, first it checks all the hardware is working, then updates the song library using tag from song. The player has features like commercial mp3 player has. There are options for play, pause, stop, skip, mute, volume control, repeat, and random shuffle. You can set up your playlist, setting screen brightness & contrast, display album image and more.
The screen is automatically dimmed after 1 minute of no user activity. When user unplug the headphones, playback is automatically paused and resumed if they are reconnected. Everything is controlled through just the trackerball which is setup to trigger 5 pin change interrupts.