video mirror on iBook

[Larry Grover]

I'm posting this in case it helps anyone else who needs (or wants) 
video mirroring on their iBook.

I've been wanting to use the video mirror on my iBook (G3 800 MHz) 
ever since I got it, so I can use my iBook to drive an extrnal 
projector for presentations.  But I've never been able to get it to 
work properly until this week.

I couldn't get any video output on the external VGA adapter under 
Warty, despite many hours of research and testing.

I upgraded to Hoary several weeks ago, hoping to get this to work, and 
it did -- sort of.  Unfortunately, although the external display 
worked, there was quite a bit of distortion on the built-in LCD panel, 
which made it pretty much impossible to use.

One of the updates I installed this week -- I think it was the new 
xorg (6.8.2-2) -- did the trick.  I now have video mirroring working 
properly, with nice clean displays on both the external 
monitor/projector and the built-in LCD panel.

Thank you, Ubuntu developers!

In order to make this work, I had to make a couple of changes to my 
xorg.conf file.

First, I removed the "UseFBDev" option.  According to the "radeon" man 
page, UseFBDev is incompatible with MergedFB (which is necessary to 
make video mirroring work).  The other two options I added are 
"UseFWPLL" and "CRT2Position".

According to the man page, "CRT2Position" defaults to clone (which is 
what I wanted), so I probably don't need this option.

The radeon man page lists many more options, but these were all I 
needed to get mirroring working on my laptop.

Here's the relevant section from my xorg.conf file:

Section "Device"
         Identifier      "Card0-normal"
         Driver          "radeon"
         VendorName      "ATI Technologies Inc"
         BoardName       "Radeon Mobility M7 LW [Radeon Mobility 7500]"
         BusID           "PCI:0:16:0"
         Option          "UseFWPLL"              "true"
         Option          "MergedFB"              "true"
         Option          "CRT2Position"          "Clone"
EndSection

The video card in my iBook is a Radeon Mobility 7500, but I think this 
is supposed to work with any Radeon card.

I anyone wants more details, let me know.


I hope this is helpful for someone else,

Larry