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4.3.6. Output parameter settings
By right clicking on an output label a dialog window appears showing the
parameters for the corresponding output. Some settings are only accessible with
Lightware PRO series routers.
Scope of changes
There are two options to apply changes. To set the scope of the changed settings,
select the desired option in the top left box.
Apply changes to current output:
this option means the modified parameters
are applied only to the currently selected port.
Apply changes to all outputs:
this option means that the modified parameters are
applied to all output ports.
Info:
When opening this window again, the scope selection will be set to
“Current
Output
” regardless of the active selection at the time of closing. It is to avoid
making changes to all outputs by mistake.
Reload factory defaults
Current output:
Reloads the default values to the currently selected output.
All outputs:
Loads the factory default values to all outputs.
Drive current
It specifies the drive current of the internal crosspoint circuit for each output. It is
recommended to leave this value at the default 20 mA setting, this produces
differentially 1 V peak to peak voltage conforming DVI specification. Alter only if
experiencing signal transmission errors. Higher output drive currents can help to
avoid problems when using longer cables. Modifications are done promptly when
selecting a value from the drop down list.
To obtain a standard 1000 mV p-p differential output (single-ended = 500 mV p-p),
the output current should be programmed to 20 mA. With an effective termination
resistance of 25 , this will generate the proper differential voltage.
Figure 4-5. Output port drive current
Warning
Drive currents over 24 mA should be used with extreme caution since this could
damage TMDS receivers in DVI sink devices!
matrix router
output port
destination
device
I
drive
+3.3V
+3.3V
OUTx_P
OUTx_N
50 Ω
50 Ω
!
