What is pocket-scion-synth?

Pocket SCION Synth is an alternative firmware for the Instruo Pocket SCION, a small hardware synthesizer built around an RP2040 chip. The original device plays back prerecorded samples, but this replacement firmware turns it into a real-time synthesizer that generates every sound live using oscillators, filters, envelopes, LFOs, chorus, and delay, with four voices playing at once. It is an independent, clean-room project, not affiliated with or endorsed by Instruo, and it does not include any of the original device's samples or code. The firmware includes 128 preset patches spread across eight banks, three rhythm lanes driven by sensor input, MIDI output over both a traditional DIN cable and USB, and a small ring of RGB lights that visually reacts to the sound's volume, polyphony, and rhythm patterns as it plays. Sensors on the device control notes, expression, tone, rhythm, and pitch bending, and can also output raw sensor data. Installing it means downloading a ready-made firmware file, putting the device into a special update mode, and copying that file onto a drive that appears when you do. The process is reversible: the same steps can be used to reinstall the original manufacturer firmware, which the project links to but does not redistribute itself. Behind the sounds, the device reads timing signals from a sensor and analyzes groups of ten readings at a time to work out patterns like variance and proximity, which continuously reshape the rhythm and melody generator. Three separate rhythm patterns pick notes from a scale and pass them to a four-voice synthesis engine built on an existing open source design, with audio sent out through a precisely timed digital audio pipeline. The project ships full documentation covering the hardware, firmware architecture, controls, and how to build it from source, and welcomes outside contributions under a defined process. The new firmware and its documentation are MIT licensed, while one vendored synthesis component keeps its own separate open license.</content>