Multiple screens.

Ville Syrjälä syrjala at
Fri Apr 8 10:32:55 PDT 2005

On Fri, Apr 08, 2005 at 10:38:42AM -0500, Leif Delgass wrote:
> Note that the TV-out feature as implemented currently and display 
> switching through the bios in general is potentially dangerous, since
> it is overriding the normal driver code to set modes (through the card
> registers) with calls to the card bios.  The driver's view of card state 
> can become inconsistent with the mode programmed by the bios.
> Although I haven't heard any examples of this causing problems, the
> normal checks of the capabilities of the displays are bypassed.
> Both for TV-out and clone/dual-head, it would be better to program the
> crtcs directly through the registers as Alex said.  For TV-out, I'm not 
> sure if all the relevant information is available to do this on mach64.

Some time ago I emailed ATI about getting the ImpactTV specs but so far 
they haven't responded. The names of the TV-out registers are known but 
not the contents. Comparing the register names with those of Rage Theatre 
(from the gatos code) it looks like the chips are related. Since they gave 
the Rage Theatre specs to someone I'm hoping they might give out the 
ImpactTV specs as well.

Ville Syrjälä
syrjala at

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