USB2VGA adapters on XO-1.5 (and XO-1 with F11 images)
Reuben K. Caron
reuben at laptop.org
Fri Jul 16 12:58:44 EDT 2010
On Jul 16, 2010, at 12:46 PM, Martin Langhoff wrote:
> On XO-1? Or XO-1.5?
> Maybe I typo'ed the rpm name...
> On Fri, Jul 16, 2010 at 12:07 PM, Reuben K. Caron
> <reuben at laptop.org> wrote:
>> Esteban found that xorg-x11-drv-sisvga is not available
>> but xorg-x11-drv-sisusb is available. Using xorg-x11-drv-sisusb
>> worked fine.
>> Begin forwarded message:
>> Message: 2
>> Date: Fri, 9 Jul 2010 17:18:47 -0400
>> From: Martin Langhoff <martin.langhoff at gmail.com>
>> Subject: Re: USB2VGA adapters on XO-1.5 (and XO-1 with F11 images)
>> To: OLPC Devel <devel at lists.laptop.org>
>> Cc: Sridhar Dhanapalan <sridhar at laptop.org.au>, sandra at laptop.org,
>> Keith Wilbern <kwilbern at gmail.com>, rsmith at laptop.org
>> <AANLkTik-oFL5gC9Roq2J97wQLysmjlJG94rTjOYN8ow7 at mail.gmail.com>
>> Content-Type: text/plain; charset="iso-8859-1"
>> On Thu, Jul 8, 2010 at 1:14 PM, Martin Langhoff
>> <martin.langhoff at gmail.com> wrote:
>> For monitors/projectors that can handle something close to 1200x900
>> 1152x864, you can use Xinerama instead. Here is an xorg.conf that
>> exactly that:
>> The Xinerama approach turned out to be a winner in terms of
>> performance and !bugginess.
>> Turns out that with a bit of elbow grease we can make it work on
>> 1024x768 which is what most projectors support.
>> - yum install xorg-x11-drv-sisvga xorg-x11-server-Xephyr
>> - Grab the files from http://dev.laptop.org/~martin/usbvga/xinerama/
>> olpc-configure goes to /etc/init.d/ , make it executable
>> olpc-session goes to /usr/bin/ , make it executable
>> xorg-xo1.5-dcon-extmon.conf goes to /etc/X11/
>> - Plug the USB2VGA device
>> - Reboot & Enjoy
>> Limitations and notes:
>> ?- Needs to be "switched on" at X startup time. olpc-configure checks
>> at boot time if sisusbvga is loaded and changes the xorg.conf symlink
>> if needed. My patch also fixes a longstanding old bug where the
>> xorg.conf was 'set' in the first boot.
>> ?- The desktop is a little bit smaller. On the XO, the desktop
>> appears in the top-left corner -- on the external monitor / projector
>> it fills up the screen perfectly.
>> - Icons can appear slightly pixellated. I think this technique may
>> expose a bug in Sugar and in some activities (ie: TurtleArt) that
>> a copy of rendered SVGs as bitmaps.
>> ?- Performance is acceptable. (We are saturating the USB 2 bandwidth
>> with the amount of pixels and the bitdepth).
>> - The Sugar cursor is back!
>> - Video works! No Xv however, so it's not particularly fast.
>> Patch to olpc-utils is attached -- I haven't tested the spec changes.
>> ?martin.langhoff at gmail.com
>> ?martin at laptop.org -- School Server Architect
>> ?- ask interesting questions
>> ?- don't get distracted with shiny stuff? - working code first
>> ?- http://wiki.laptop.org/go/User:Martinlanghoff
> martin at laptop.org -- School Server Architect
> - ask interesting questions
> - don't get distracted with shiny stuff - working code first
> - http://wiki.laptop.org/go/User:Martinlanghoff
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