This is a simple design for an incredibly cost-sensitive DCO module for eurorack format modular synthesizers.

Firmware was written with Arduino, using @brendan0powers's Xmegaduino fork. To program, use the following avrdude command from the firmware directory, using an avrismpmkII:

avrdude -patxmega32a4 -cavrispmkII -Pusb -Uflash:w:firmware.hex

This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.