[Coco] Including an SSC

[jmlaw at iprimus.com.au]

Simon Jonassen wrote:

>Just my 2c

>He who says the AY chip is simple... FAIL !

>Far from it !.....

>This is the same chip as in the SSC (AY) making incredible sounds on a ZX
>spectrum:

>http://roust-it.dk/coco/AYCHIP/01-Yerzmyey-Why.mp3

Not sure i this is directed at me or at Richard's comments as there was no 
quote but I'll try to clarify what I meant by simple.

I know you have read the manual and have shown me the links before too, but 
this is more to clarify for those reading along.

Simple to Program:

It's simply a programmable tone generator at the most basic level (555 timer 
IC tone generator example for some kind of simple reference others may have 
used before)

Programmable amplitude control:

Extra hardware envelope functions if you choose to use them, but not the 
best way IMHO. They only control the amplitude in predefined ways. I can 
almost get a decent tri-wave using it but it's not good for much. I tried :)

Like anything, it's performance potential will depend on how complex the 
code is that controls it.

But for NES style background music, this was the closest thing we have for 
the CoCo and why I chose to pursue this route.

It does a very good job with so little overhead that my game port can still 
run at 60fps with the 1 & 2 pixel increment horizontal scrolling, level 
updating, 3 (maybe 4) channel background music & simple sound effects and 
hopefully the entire main loop of the game complete every frame. I'm 
focusing on getting it all together as a "canvas" to then add the main loop.

So yeah while it can do some incredible things with full CPU dedicated time 
(more than I have interest to pursue in that direction personally, but great 
for your demo-scene stuff), the fact that it is simple to setup, simple to 
control with so little overhead makes it perfect for games. In that sense, 
simple is a great thing :)

Not to say Nick's idea for the sampled sounds wouldn't be great too, it most 
surely would. The simplicity to control it without CPU dedicated time is 
what makes it great for games also.

Again just to clarify for others.

Jason