This embedded MP3 module is an universal and compact circuit for playing MP3 audio files. The MP3 module can be used in embedded systems.
The MP3 files (up 65,536) are stored in a micro SDcard.
Controlling the module could be done either by buttons and digital inputs or via TTL serial interfaces.
The MP3 module is based on MP3 converter VS1011 from VLSI and a Microchip PIC24FJ64GA002 and can play up to 65,536 songs or voice messages stored in a microSD. Each track can be selected via serial lines or by using 9 buttons or switches. If you choose the serial communication you have to use a microcontroller, using the 9 digital lines you can control the player with logic signals from stations of various kinds, such as tension-indicator lamps, relays, etc.. The module can be used to play voice messages in vending machines, telephone systems, in the car to inform the driver of the vehicle’s condition and environmental ones, in alarm systems, to assist configuration and inform about events that occurred, and in many other areas yet. The device supports micro SD with capacity up to 16 GB and can be powered with a voltage of 3.3 Vdc or 5 Vdc selectable. The module has a single in-line single-connector positioned on one side of the PCB, so you can better manage the space and mount it also in upright position.
In “Pin-to-Pin” mode is provided the use of three buttons (PLAY / STOP, VOL UP and VOL DOWN) and a 6-way DIP switch connected to the module, while “Serial” mode the serial communication is with TTL signal level. The device can also be used in “Mixed” mode that allows you to issue orders both with serial port and pin-to-pin input.
The names of MP3 files must be a number from 0 to 65535 followed by the extension .mp3 (for example, 0.mp3, 1.mp3, 2.mp3, 3.mp3 16.mp3 … … 65535.mp3).
Schematic and PCB - download
Part 2 - Configuration of the module, Software