Re: [hatari-devel] TT palette bankswitching should be supported

[Eero Tamminen <oak@xxxxxxxxxxxxxx>]

Hi,

Looking at Roger's test program (which doesn't change
any palette entries, just queries them after changing
bank), it's not enough to map ST palette writes, also
reads need to be mapped.

And as byte sized writes to ST palette entries need
to be blocked, I think I need to re-write the palette
handling so that both ST palette writes AND reads are
directed to suitable TT palette entries.

CPU core can manipulate ST palette registers directly,
but they're used just on writes, not on reads.


	- Eero

On 02/23/2016 07:55 PM, Thomas Huth wrote:
> Am Sun, 21 Feb 2016 22:56:14 +0200
> schrieb Eero Tamminen <oak@xxxxxxxxxxxxxx>:
>
> > Hi Roger,
> >
> > On 02/21/2016 07:26 AM, Roger Burrows wrote:
> > > On 21 Feb 2016 at 1:00, Eero Tamminen wrote:
> > > > Ah, so this isn't about ST<->TT color palette mapping,
> > > > but about e.g. 16/4/2 color modes.   Both TT and ST modes?
> > > It applies when bank-switching is active, so should apply to ST
> > > low, ST medium, and TT medium.  I originally tested just TT medium,
> > > but I've now tested ST medium & ST low and (as per the Atari
> > > documents), it applies to all 3.
> > >
> > > Note that this does not apply to any other TT mode (ST
> > > high/duochrome, TT high, TT low).
> >
> > Thanks for the testing!
> >
> > Could you send the test program you mentioned?
> >
> > Attached patch hopefully fixes that.
>
> You might also need to set bTTColorsSync = false in case the
> application writes to the TT shifter mode register?