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

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Bank number is taken into account in the ST & TT color register writes.

	- Eero

On 02/19/2016 08:05 PM, Roger Burrows wrote:
When running in ST Low, ST medium, or TT medium, the TT video hardware supports
bankswitching for the palette: the part of the TT palette that maps to the
STe-compaitble palette can be changed, by changing the "bank number" in the TT

After power-on reset, the bank number is the set to zero, which causes the
first 16 TT palette registers to map to the STe palette registers.  If you set
the bank number to N, then TT palette registers 16*N to 16*N+15 are mapped
instead.  There is even a special TOS3 XBIOS call, EsetBank(), to do this.

Hatari does not support this.

In video.c, function Video_TTShiftMode_WriteWord(), I think that there needs to
be a check for bank number, which would then be used (I don't want to guess
where) to do the mapping.

Tested on a real TT, and documented in "Atari TT030 Hardware Reference Manual".


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