Re: [hatari-devel] New SCC 85C30 support for MegaSTE/TT/Falcon

[Eero Tamminen <oak@xxxxxxxxxxxxxx>]

Hi,

On 4.9.2023 23.45, Nicolas Pomarède wrote:
> over the latest months I spent some time (slowly) rewriting SCC 85C30 
> emulation in Hatari.
> This chip is used in MegaSTE / TT / Falcon as a high speed serial 
> interface but also as a LAN interface.
>
> It's a rather complex chip with 2 channels (each one can drive a 
> physical interface), with *lots* of registers to program it and a huge 
> doc (nearly 400 pages), so it was quite some work to understand its 
> inner working and emulate as much as possible for Hatari.

Looking at SCC related regs in this:
https://ftp.lip6.fr/pub/atari/Docs/hardware.txt

They seem to differ between all the related machines (MSTE, TT and 
Falcon).  Does code take that already into account?

....
> It's quite possible I broke some things when rewriting SCC code, but 
> just booting Freemint is already using channels A and B interrupt as 
> well as many registers so hopefully there should not be too many things 
> to fix :)
>
> Does someone know some programs that will use the SCC for serial 
> transfer ? If so, does it still work ?
>
> When serial transfer is confirmed to work, we can add support for more 
> physical interfaces, as they were used on MegaSTE / TT /Falcon

Once you have that, I could help in adding the CLI options and updating 
the docs accordingly.

I'm not sure where to fit SCC options in SDL GUI though, "Devices" 
dialog is pretty full...


	- Eero