10
EDID NOTES
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 cater 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 8x1 DVI Switcher
The 8x1 DVISwitcher 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 8x1 DVISwitcher
to insure that EDID is recorded and retransmitted properly, otherwise display of
input sources might not happen correctly (or at all).
Managing EDID with the 8x1 DVI Switcher
The 8x1 DVISwitcher has the ability to use 2 modes for routing EDID.
1. The default mode is the LOCAL mode which will store the EDID of a source
device (one for each input) into the 8x1 DVI Switcher. The EDID stored in
each LOCAL location can be from a local display device or from a remote
source over the RS-232 serial communications port. The 8x1 DVI Switcher
includes a built-in EDID memory bank which can store up to 7 separate
EDID data structures which can then be loaded to each of the LOCAL EDID
locations.
2. The second mode is the DS (Down Stream) mode which functions as a
simple EDID pass-through. In this mode, the display device connected to the
8x1 DVI Switcher will pass its EDID directly to whichever DVI input source is
currently selected.
How do I change EDID modes in the 8x1 DVI Switcher?
There is an bank of 4 DIP switches located on the main circuit board on the
underside of the 8x1 DVI Switcher. DIP switch 3 can be used to set either the DS
or LOCAL EDID modes.
TIP:
Advanced EDID functions can also be managed via the RS-232 serial
communications port. See page 13 for more information on the RS-232 serial
communication features.