TAG: library

arduinOSC is a library which transforms your arduino into a simple arbitrary waveform audio oscillator.
It is based upon the internal 16-bit programmable timer and generates audio using pulse width modulation (PWM) and an external low-pass filter (square waves don't even need the external filter).
I'm using a simple passive low-pass filter, but in the next days I'll try an active low-pass filter based solution.
The library includes a sine wave lookup table (LUT) and a user-definable lookup table which can be found in the file named "user_waveform.h" under arduinOSC folder: if you whish to change this waveform just edit the file and then delete "arduinOSC.o", so the next time you will compile your sketch the library will be rebuilt.
Square waves are generated without a LUT, and in the next version also triangle, ascending sawtooth and descending sawtooth will be generated in this way, so the LUT will be used just for sine and user defined waveforms.
So far the library has been tested with Arduino Nano and Arduino Diecimila with the new ATMega328P.

I've been a Maschine user for almost two years now, and it's well integrated in my usual setup. Since a few months, though, I've been more and more involved into modular synthesis, and the amount of eurorack modules in my case has been slowly but constantly growing.
I've built oscillators, filters, LFOs, VCAs, a bucket brigade delay unit, yet there was something very important missing: I needed an hardware sequencer!

Of course I was already having fun with a CVPal and my laptop, but somehow it felt weird having to use a mouse to shape my sequences, when all the sounds were created and processed on my modular synthesizer.

Then I decided that it was time to build a simple CV/gate sequencer: I took inspiration from some nice and interesting open source projects (MIDIAlf with CV board and Sonic Potions LXR, to name a couple) and put together some prototypes using breadboards and Arduino.
That was a lot of fun, but... wait a second!  Did I really want to build a dedicated hardware control surface from the ground up? Of course it would have been great and rewarding, but would have required quite some time, and I wanted to be rather focused on the sequencing engine and the software features (well... who knows, if the next Berlin winter is long enough I might also spend time designing some hardware).

Anyways. All of a sudden that Maschine MK2 laying on my desk started to look even sexier... loads of buttons, RGB leds, endless knobs and two 256x64 monochrome displays! But how to use it? No, I wasn' t going to tear it apart and cannibalize some pieces, I had to find a less "intrusive" solution.
What about trying to reverse the communication protocol in order to be able to use the original hardware with a whole new application logic? Maybe even wihout connecting it to a computer? That' s how it all started...

It’s been quite some time since my last post, and you might wonder about the status of the library I announced a few months ago… well the bad news is that it’s taking waaaaay longer than I expected, but the good news is that I’m still working on it and most of the hard work has already been done.

So what’s the current status?

• The graphic library and the display abstraction layer have been completed and tested on Maschine MK1, Maschine Mikro MK2 and Maschine MK2 (I still have to test it on Maschine Mikro MK1 though…)
• The Windows/Mac/Linux usb communication layer is 100% working
• The SAM3X communication layer is currently being implemented
• I already started to write some demo applications (as you can see in the video below)

Synapse is a simple, diy-friendly Arduino shield that will allow you to expand your modular synthesizer in new and creative ways. Here's the hardware features:

• 2 x control voltage inputs, 0 to 5V with diode protection
• 2 x control voltage outputs, individually configurable as 0 to 10V or -5 to 5V via software, with 12bit of resolution
• 2 x gate inputs
• 2 x gate outputs
• 1 x eurorack power connector (10 pin)

Please refer to the github repository for the latest version of the schematic, the BOM and the library. Please note that for the time being I'm not selling kits or pcbs, you'll have to order the pcbs yourself and source all the parts (see the links and infos below).