AY-3-819x in VHDL

Copyright 2018 Jiri Svoboda

This is an attempt to create a design compatible with the AY-3-819x programmable sound generator in synthesizable VHDL.

Compiling

You need Linux or similar OS with GHDL and GNU Make. Simply type:

$ make

This builds all the units and the test binaries.

Running tests

Simply run the individual test_xxx binaries. Typically, the output must be verified manually for correctness.

Synthesizing

I haven't attempted to synthesize the design yet. There is more than 100 bits worth of registers so if you are targeting a CPLD, it would have to be a pretty big one.

The top level unit is psg (in psg.vhd). It should allow synthesizing a signal-compatible circuit to the original AY-3-819x, except that it does not provide analog outputs. Instead it provides digital volume level and polarity for each channel. I am looking into whether it is possible to provide PWM output as well.

TODO

Register file test bench PSG test bench IOR playback