VGA out/External Monitor on ibook 2

Michael Schmitz schmitz at
Tue Feb 11 03:24:21 EST 2003

> > Someone lately posted a message detailing the problem (either here or on
> > debian-powerpc): the hsync and vsync pulses appear to be OK (correct
> > frequency) but have a phase jitter.
> Unless somebody else posted it too, that would be me. And I now realise
> that it was based on your suggestion (on debian-powerpc) a year back!

Possible - I've suggested someone take a scope and debug this more than
once :-)

> Owen asked: How was it using OFFB? The phase is steady with the OFFB.
> > Does that ring a bell with anyone
> > here? Does anyone know which PLL setting the hsync position is derived
> > from?
> >
> > 	Michael
> Is it possible that the lcd and crt *have to be* on different
> controllers? From what I understand,  OF and OSX set it up that way but we

Yep, that's entirely possible. Maybe we can't get the proper specs for
both on one controller.

> don't. As I have no documentation, this is just  a conjecture.
> Still I would like to do just that. But I am constrained by the lack of
> documentation. Pointers anybody? Maybe people who desire a dual-head would
> like to help :)

I'd talk to Michel Dänzer about this. The XFree people might have figured
something out on other (i386) architectures. XFree developers have access
to at least some ATI docs.


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