Hardware Reference
In-Depth Information
Create a new file in your home directory called
xorg.conf.mimo
and open it in your
favorite text editor. (If you don't care about the inner workings here, you can just
Your Xorg cofiguration file needs five sections: Device, Monitor, Screen, ServerLayout,
and InputDevice:
Section "Device"
Identifier "DisplayLinkDevice"
driver "fbdev"
Option "fbdev" "/dev/fb1"
Option "ShadowFB" "off"
EndSection
This defines a video device named
DisplayLinkDevice
that uses the
fbdev
driver across
the Mimo's framebuffer device (
/dev/fb1
). If your framebuffer device is different, ad-
just it accordingly.
We also disable the
ShadowFB
feature. ShadowFB causes the
fbdev
driver to force the
CPU to do each drawing operation first into a shadow frame buffer in system virtual
memory and then copy the result into video memory. While this behavior is good for
most cases, for our DisplayLink device, you need the CPU to draw directly into video
memory:
Section "Monitor"
Identifier "monitor"
Option "DPMS"
EndSection
This section defines a Monitor device, which we have uncreatively named
monitor
. The
only other setting here is to enable Display Power Management Signaling (DPMS),
which allows power saving behaviour of the touchscreen when you are not using your
Raspberry Pi:
Section "Screen"
Identifier "screen"
Device "DisplayLinkDevice"
Monitor "monitor"
EndSection
The third section defines a
Screen
device that ties our
DisplayLinkDevice
video device
to our
monitor
device. This is how Xorg works; it draws to a screen device. Xorg sup-
ports multiple devices, including multiple screen devices, but for this hack, we're
keeping it simple:
Section "ServerLayout"
Identifier "default"
Screen 0 "screen" 0 0
