Sunday, October 16, 2011

Atmel Attiny45 / Attiny85 based USB MIDI controller

Today I made a MIDI controller out of an Attiny45 and a potentiometer.

This project implements the V-USB firmware from Objective Development to emulate a class compliant audio / MIDI stream device using an Atmel AVR microcontroller. It is based on the V-USB-MIDI project by Martin Homuth-Rosemann and partly on the 4-key-keyboard project.

The nice thing about this project is that it takes advantage of the internal RC oscillator of the Attiny and therefore not even needs an external crystal.

Hardware needed:
  • 1x Atmel ATTiny45-20PU or ATTiny85-20PU microcontroller
  • 2x Diodes (1N4148)
  • 2x 68 ohm resistors
  • 1x 1.5K resistor
  • 1x 0.1 uF capacitor
  • 1x 10K potentiometer
  • 1x USB cable with USB-A plug
  • Programmer for Attiny45 / 85


The Fuses have to be set to 0xC1 (low), 0xDD (high) and 0xFF (ext.). 

The PID and VID used in this project are sponsored by Objective Development.
AVR is a registered trademark of Atmel Corporation.

Download the project and the .hex file here. It should work equally well on both the Attiny45 and the Attiny85.