Gefen EXT-DVI-441DL - Manual (Page 13)

10
EDID MODES
What is EDID and what is it used for?
Under normal circumstances, an audio/video source device (digital or analog) will
require information about a connected device/display to assess what resolutions
and features (capabilities) are possible. The source device can then tailor its
output to create resolutions and/or features that are compatible with the attached
device/display. This capability information is called EDID (Extended Display
Identifi cation Data). A source device can only accept and read one EDID data
structure/record from a connected source device/display. Likewise, the source
device can output only one video resolution to a connected device/display.
The importance of EDID with regards to the 4x1 DVI DL Switcher
The 4x1 DVI DL/SL Switcher handles multiple sources/inputs. Each connected
source device must correctly read one EDID data structure in order to address its
display device correctly. EDID management is carefully handled by the 4x1 DVI
DL Switcher to insure that EDID is recorded and retransmitted properly, otherwise
display of the input sources might not occur correctly (or at all).
Managing EDID with the 4x1 DVI DL Switcher
The 4x1 DVI DL Switcher uses 2 modes for routing EDID. They are:
1. When the local EDID Mode is ON, (factory default setting) the Switcher
copies the EDID of the connected display to the local memory location as
they are selected. Each device must fully “boot up” before you can select the
next input. The connected device derives EDID information from the local
memory location.
2. When the local EDID Mode is OFF, each time a new source device is
selected, the Switcher connects EDID from the attached display to the
currently selected input source.
Both modes are described in greater detail on the opposite page.
NOTE: The 4x1 DVI DL Switcher also features an EDID Lock Mode, allowing
the EDID to be stored. See the following page for details.
How do I change EDID modes in the 4x1 DVI DL Switcher?
There is a bank of 4 DIP (Dual Inline Package) switches located on the main
circuit board of the Switcher underneath a small piece of silver grey tape on the
underside of the Switcher. When the sticker is removed, there will be two DIP
switch banks visible, one with 4 switches and one with 8 switches. The 8-switch
DIP switch bank is not used here (it is used for the DL (dual link) feature covered
later on page 12.)