Well, the code I’m referring to is here – it hasn’t been updated in over 6 years but it’s still archived and downloadable, and it functions quite well (at least the version compiled to run in OpemEmu under OS X does).
http://www.zophar.net/a7800/prosystem.html
I downloaded a copy myself so I know the link is still alive/working. I haven’t seen that thread at AtariAge but I’ll check it out, thanks!