[Coco] Sound/Speech Cart

[Alex Evans]

I have been playing around with some code to drive some of the various AY
sound options for the CoCo from assembly language. I have had success with
the SuperSprite FM+ (easiest) and the Philharmonic-12 (Symphony-12 clone),
but I haven't had any luck with the Sound/Speech Cart. In the course of
trying to figure out what the problem is I have gone through the BASIC
examples in the manual and even tried to replicate them in assembly
language. I can drive speech from assembly, but not any of the AY
functionality.

Additionally this has led me to find that the longer demo program in the
manual has a number of bugs. The biggest of which is that when it uses
direct register access to the AY, it waits for the sound to end (which it
won't) rather than just having some delay.

If there is anyone who has called the AY in the SSC from assembly language,
any pointers would be appreciated. I do check that busy* is high before
sending data to the SSC. I do send the reset signal to the SSC before I do
anything.

Thanks