[Coco] SSC and emulation

[jmlaw at iprimus.com.au]

Tim Linder wrote:

>On Fri, Oct 10, 2014 at 6:32 PM,  <jmlaw at iprimus.com.au> wrote:
>> I too am working on a game and mine uses the SSC in direct mode. While 
>> I've
>> considered alternatives for those who don't own an SSC or prefer to use
>> emulators, for those who don't own a SSC or can't find one to buy,

>I have an incomplete driver for MESS that supports the SSC in direct
>mode. I wrote the TMS70x0 core in MESS and it is good enough to work
>with the PSG.

>It also worked with direct mode with the speech chip. If I recall 
>correctly.

>But it failed with text to speech conversion, so I've been holding it back.

I’d been meaning to ask you about it. Back when I saw your page about SSC 
emulation, I hadn’t seen you around and figured you may have moved on.

While working with the SSC, I came across a sang; I had to include a delay 
loop after resetting the SSC as it wasn’t ready to receive commands/data, 
although ready register said it was. You mentioned their was a bug somewhere 
you couldn’t find so I just thought I’d mention that the real hardware seems 
to have a bug too that may have been causing you grief. I didn’t realize the 
Speech chip had direct access, but then I have no interest in the speech 
side personally. In my experience and humble opinion, It’s fun for the first 
10 mins but then gets old fast :)

But I also understand that f you're going to emulate the SSC you'd much 
prefer to do it completely than just add the AY support. Just wondering if 
you too had trouble with the SSC not being ready after sending the SSC reset 
command? It *may* be affecting the speech emulation???

Another issue is the later builds of MESS won't sync at 60 FPS properly 
(unless I'm missing something), so unless that is fixed (beyond my skill), 
the added SSC support, while perfect for many older games, and absolutely 
still worthwhile to add, my particular game still won't be playable without 
the sync issue. But perhaps when I release some code, if there's any CoCo 
contributors to the MESS project about they could take a look at it. But I'm 
not quite there yet so I'll save getting deeper into that for another 
time...

Jason