The OPA Arduino Shield

OPA is an inexpensive FM Music synthesizer for Arduino thatís bursting with character.


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Front view
The shield is powered with a tiny but powerfull dsPic33EP256MC202 16bit / 140Mhz microcontroller from Microchip and offers the following characteristics:

Project story

Inspired by the classic sound-chips found in 90's video game consoles, keyboards and sound cards, OP∑A gives your next project retro flavored sounds and music, all through a simple serial interface. It has been design to be:

About FM synthesis

The sound of FM synthesis has had a profound influence on more than a generation of musicians and music lovers. It has also played an important role in the history of video game music. The development of dedicated circuits like the OPL series allowed PC and console gamers to enjoy high quality sound while not taxing the CPU. For more than a decade, the sound of FM was the sound of gaming. Popularized by Yamaha during the 80s, FM synthesis was at the heart of many famous instruments such as the DX7 and consoles such as the Sega Megadrive and Genesis.

System diagrams

Project downloads

OPA Reference manual 0.1 (24.01.2016)
OPA Booklet (page 1)
OPA Booklet (page 2)
OPA Memosheet

The lastest version of OPA editor:
OPA editor 1.11 (13.08.2016)
Windows (XP / Vista / 7 / 8 / 10)
MacOS X (from 10.7 - app bundle)
MacOS X (from 10.7 - dmg)

OPA editor 1.10 (04.07.2016)
Windows (7 / 8 / 10)
MacOS X (from 10.7 - app bundle)
MacOS X (from 10.7 - dmg)