4bitsynth
Copyright 2008 David M. Farler
http://code.google.com/p/4bitsynth/

contact: [email protected]

4bitsynth is a MIDI-controlled digital synthesizer that uses the Atmel AVR ATMega48. The inspiration is from the NES. As such, the sound is 4-bit. The 4-bit digital output is put through an R-2R resistor ladder to get the analog waveform.

Building instructions and schematic are available at the wiki:
http://code.google.com/p/4bitsynth/w/list






====================================== COMPILING =========================================

Each synth has its own makefile: Makefile.square, Makefile.triangle, Makefile.noise

However, you can just build all of them at once by executing the buildall.sh script:

./buildall.sh



To make each one separately, enter the following at the commandline (example square shown)

make -f Makefile.square hex

or

make -f Makefile.noise hex

or

make -f Makefile.triangle hex







====================================== PROGRAMMING =========================================

The makefile references AVRDUDE as the programming application. 
Alter the makefiles to change to which type of programmer you are using (stk500, usbtinyisp, or perhaps avrispmkii).

The make command for uploading is:

make -f Makefile.square writeflash

or

make -f Makefile.noise writeflash

or

make -f Makefile.triangle writeflash