APANTAC LLC
www.apantac.com
14
OG-US-4000 User Manual
Trouble-Shooting:
Introduction:
HDMI video involves three requirements that may cause issues; Hot-Plug, EDID, and HDCP.
Hot-Plug (5-Volt and Hot-Plug lines):
Also known as Hot-Plug-Detect, HDMI cables utilize two separate wires to perform this ‘hand-shake’ between the
source and the sink (OG-US-4000). The source provides 5-volts on pin 18, the 5-volt pin. In response the sink
provides 5-volts on pin 19, the Hot Plug Detect pin.
EDID (External Display IDentification):
The HDMI input port of the OG-US-4000 provides EDID to your source equipment. This EDID can be the factory
default or the user may copy an EDID from a monitor or downstream equipment.
The source reads EDID from the OG-US-4000 through the DDC (Display Data Channel) wire of the HDMI cable.
This DDC channel utilizes a version of the I
2
C communications protocol. Typically the EDID is read after the HDMI
cable is plugged into the monitor or when the source boots up.
Most HDMI sources adjust themselves according to the EDID they see from the equipment they are connected to.
For instance; if you connect the source to a monitor it may display fine because it is producing a signal appropriate
for that monitor. When you move the source cable from that monitor to the OG-US-4000 it may very well change
the signal it is outputting because it is now seeing a different EDID. Changing the OG-US-4000 EDID is one
method of changing, or controlling, your source’s video signal.
See the “Display Tab” section for instruction on changing the EDID.
If you do not have an appropriate monitor to copy EDID from, Apantac Technical Support can assist with procuring
or customizing an EDID.
HDCP (High Definition Content Protection):
If you suspect HDCP may be the cause of your issues please contact Apantac Technical Support. Our telephone
number can be found on our website.
Audio issues:
Audio issues can generally be resolved by changing settings within your source equipment or by changing the OG-
US-4000’s EDID. Most Blu-ray players for example have configuration settings pertaining to their audio output,
changing these from Dolby to PCM can often alleviate problems.
EDID can include audio requirements. Changing the EDID may change the audio signal or audio protocol the
source provides.
