Re: [hatari-devel] ST bus error results

[Thomas Huth <th.huth@xxxxxxxxx>]

Am Sat, 28 Apr 2018 12:06:23 +0200
schrieb Christian Zietz <czietz@xxxxxxx>:

> Thomas Huth schrieb:
> 
> > Would be interesting to
> > know whether Ricoh chips have still been used for Mega-STs, or if
> > all Megas were already shipped with an IMP chip...  
> 
> I think that Megas were also shipped with Ricoh chipset. Browsing the
> Mega ST mainboard photo gallery at
> <https://www.exxoshost.co.uk/forum/viewforum.php?f=55>, one finds two
> mainboards with Ricoh chips.

Wow, ok, thanks for digging that out!

> However, I wonder how to integrate this into Hatari. A chipset
> selection option would be too technical for most users, I think.

Yes, I agree. Well, since the IMP chipset was AFAIK mainly used on
later revisions, and the Mega-STs came later than the original STs, I
think we could simply continue with the current approach and just
update the comments in the source (and maybe the documentation) a
little bit, i.e. plain ST = Ricoh chipset, Mega-ST = IMP chipset.

> PS: Note that the IMP chipset not only differs in terms of bus error
> generation but e.g. also in terms of handling of memory banks by the
> MMU.

Right, Nicolas already implemented some stuff in stMemory.c for this. I
think we should then just switch the Mega-ST over to IMP behavior. Does
that sound ok for you, Nicolas?

 Thomas