tendigits/multi

USB to DIN midi converter/filter/router, sound generator

multi

What is multi?
multi is an open hardware circuit board hosting a powerful Seeeduino XIAO, 6 pots, 2 pushbuttons, 2 Midi DIN connectors and an audio output.
The Seeeduino XIAO board carries the powerful ATSAMD21G18A-MU which is a low-power microcontroller and has 14 GPIO PINs, a DAC output and one UART interface. To avoid grounding loops the MIDI input is properly opto-isolated, as required by official specifications.

Bend multi to your needs
The strong point is that you can program your multi as you need, using the Arduino IDE. On the MIDI side, possible use includes advanced midi controlling, filtering and remapping as well as algorhitmic arpeggiators and aleatoric patch generators. It's also perfect to explore digital synthesis techniques.

Software
Up to now, the available software is:

• default software, that comes preprogrammed on the XIAO board, it's a six oscillators drone machine that is also a midi controller.
• bytebeat player allows to play algorithmic music with no instruments and no real oscillators but a math expression that creates an audio output waveform as a function of time, processed 8000 times per second. The expression has six parameters accessible through the multi knobs.
• midi converter is a USB to 5 DIN bi-directional MIDI converter.
• midi metronome takes the MIDI clock from the 5 DIN midi connector and generates a metronome click on the audio output, to allow acoustic musicians to synchronize their performance to an electronic setup.
• hardware test if you have choosen the DIY kit you may want to use this software to test your build.
• blink the ubiquitous blink sketch.

Sound generation
Since the Xiao board has a DAC, multi can also be used to produce sounds using the Mozzi sonification library written by Tim Barrass or accessing directly to the DAC output.