[Coco] COCO PSG - It's alive!

[Zippster]

It's alive!

Here's a video of the most recent board I've been working on getting some initial testing. 
This sound chip board, the COCO PSG, adds 1MB of combined FLASH and SRAM as well 
as a Yamaha YM2149 sound generator.

Test video
<https://drive.google.com/open?id=0B1sgl615FlGneHhvVmw2WTg3QWc>

The board supports switching the sound generator frequency to either 1 or 2MHz.  The first tune, 
Space Debris, is a CPC chiptune being played back with the 1MHz clock.  The second, Seagulls,
 is (I think) from the ST scene and uses 2MHz.

These are both 50Hz register dumps.

There's quite a bit of chiptune music that can be easily converted for playback on this for our CoCos, 
and the possibility of making new tunes. I love this sound chip stuff, lots of fun... :D

Merry Christmas everyone!!! :)

- Ed