dco4 is a quad digitally controlled oscillator. The waveforms are output by simple 8-bit r2r ladders. The board is controlled via an SPI interface. The analog outputs are single rail 0v to 5v. An atmel attiny26 runs the show.
The dco4 code is written for my avr forth assembler. It supports individual control of each oscillator. The following commands are supported:
| description | command | data | ||
|---|---|---|---|---|
| 0 | 1 | 2 | ||
| set phase increment | 0x | phase increment | ||
| set waveform | 1x | waveform number | ||