Demo and tutorials

dual trigger/gate to CV

This product is available as a DIY project, PCB’s and front panels are available in the webshop.

STM32DUINO dual trigger/gate to CV is a module based on a low-cost Arduino-compatible STM32F103 development board and the popular MCP4822 12-bits DAC. This powerful 32bits ARM processor is in a easy to use through hole format and pack a lot of power for just about 2 dollars. The open source firmware allows you to learn programming for synthesizers as well as creating your custom firmware for your own application. It could be any function that generates CV based on a trigger/gate input, think about an ADSR, a dual LFO, a random CV generator, a algorithmic melody generator, a digital drum synthesizer, … It has also educational purposes and I made a couple of tutorial videos about the hardware and software.

This project is using the popular MCP4822 12 bits DAC. Both outputs can be either unipolar (0-10V) or bipolar (-5V to 5V).

2 default firmwares are available for the module : ADSR and LFO.

LFO features:

  • dual LFO
  • clock dividing/multiplying available on board
  • 8 waveforms
  • LFO #2 can be synced to LFO#1 or not
  • can be pinged to tap input
  • or can be free-running with 3 frequency ranges (S / M / L – 50hz-100hz / 1hz-50hz – 1hz-1min)

ADSR features:

  • single envelope
  • gate and retrig input
  • inverted output available
  • end of output customisable (end of attack, end of decay or end of release)
  • logarithmic or linear curves
  • cycle mode
  • 3 time ranges (S / M / L )

A simplistic build with a BOM of around 35 euros and a PCB set price of 35 euros.

Documentation (PCB v1.5 – WHITE):

Old Documentation (Original PCB – GREEN):