MP3 Trigger

via Pololu
SKU PL-2195

New version available: This board has replaced by the newer MP3 Trigger V24, which includes firmware improvements that make it easier to use without needing a separate microcontroller.


The heart of the MP3 Trigger board is the Cypress PSoC CY8C29466-24SXI microcontroller which serves up MP3 data to a VLSI VS1063 audio codec IC. This version also supports an optional initialization file that can be used to set the serial port baud rate as well as to reprogram any of the 18 trigger inputs to alternate functions, including random and sequential track selection, transport controls and even volume up/down. Each conventional trigger can be set to either allow immediate restarts, or to lock out restarts if audio is playing. Also, a new trigger filename convention provides greater flexibility in naming your MP3 tracks and makes file management easier.

There is also a “Quiet Mode” feature that can be enabled via the serial control port. In this mode, the trigger inputs don’t start tracks directly, but instead produce a serial message indicating which triggers were activated. A host microcontroller can thus monitor the trigger inputs and then start any track or sequence of tracks via the serial control port, making the triggers much more flexible.


  • Input voltage: 4.5-12 VDC
  • Current consumption: 45 mA idle, 85 mA playing
  • File system: FAT16/FAT32
  • Audio out: 1/8" (3.5 mm) stereo headphone
  • Trigger inputs: 3.3-5 V, active low inputs with internal pull-ups
  • Interface: TTL serial, full duplex, 8N1, 38.4K baud
  • User guide (1MB pdf)

Note: SparkFun calls this product the “MP3 Trigger” SKU: WIG-11029.