MIDI-Controlled Digital Synthesizer

4bitsynth is 4 bit MIDI-controlled digital synthesizer inspired by the NES. The project is built around Atmel AVR ATMega48 The digital output is put through an R-2R resistor ladder to get the analog waveform. It has three type output : Square wave, Triangle wave and noise.

Project Features Detail :
Triangle

* One volume (uses up/down counter)
* Pitch sweep (up/down, optional looping)
* Standard pitch bend
* Fine pitch bend


Square

* Three duty cycles: 12.5%, 25%, 50%
* Volume decay (optional looping)
* Pitch sweep (up/down, optional looping)
* Standard Pitch bend
* Fine pitch bend

Noise

* Two modes: 93-bit and 32k (think NES)
* Volume decay (optional looping)
* Pitch sweep (up/down, optional looping)
* Standard pitch bend
* Fine pitch bend
more