34
INST
ALLA
TION
CONFIGURA
TION
OPERA
TION
Fur
T
her
INF
orm
A
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INDEX
Keyboard Control
This option displays a keyboard control dialog and is useful for sending keyboard
combinations (to the host) that are needed regularly or that are trapped by the ALIF
2112T.
When entering codes:
+ means press down the key that follows
– means release the key that follows
+– means press down and release the key that follows
* means wait 250ms (note: if a number immediately follows the asterisk, then
the delay will equal the number, in milliseconds)
It is automatically assumed that all keys specified will be released at the end, so there is
need to specify -Ctrl or -Alt if these keys are to be released together.
Examples:
‘Ctrl + Alt 12’ would be expressed as: +Ctrl+ Alt+1–1+2
+N means press the ‘N’ key
+Scroll means press the Scroll lock key
+Space means press the space key
Click to send
the code
Enter the
code here
Click to send the
contents of the
clipboard to the host
Click to send
the code
Click to send the
contents of the
clipboard to the host
Ignore Dithering
Dithering is a technique used by some
graphics cards to improve perceived image
quality by continuously slightly varying the
color of each pixel. This gives the illusion
of more shades of color than the display
can really reproduce, and smooths the
appearance of gradually shaded areas in
images. Unfortunately, dithering is an issue
for KVM extenders because it makes the
image appear to be changing all the time
even when it is static. This means that a
great deal of unnecessary network data is
sent to the VNC viewer, reducing the video
frame rate and making mouse response
appear slow.
The ‘Ignore Dithering’ option works by
ignoring small variations in the video from
frame to frame. This increases performance
and reduces network traffic when the
host computer is an Apple Mac or another
computer that has dithered video output.
It also improves performance if the video
source is noisy (e.g. from a camera or a
VGA-to-DVI converter). ‘Ignore Dithering’
is disabled by default to give full color
accuracy and the best possible frame rate
from non-dithered video sources.
Video settings
This option provides a range of options related to the video configuration.
Note: If using the Paste Clipboard feature, within the VNC viewer properties, ensure that in the
Inputs section, the Share clipboard with server option is enabled. See
Appendix G
for details.
Video source
Selects which video input to
use. It is possible to display
both single head screens (if
connected) or select one
over the other. If you are
viewing Dual-Link video
resolutions, only one head
will be available.
use remote ddc
Uses the DDC of the
monitors connected to the
ALIF Reciever. If this option
is un-ticked you can select a
DDC to use that is reported
by the ALIF 2112T.
hot Plug detect
When ticked, allows you to
choose one of four hot plug
detect periods when, after
a display is connected, the
DDC information is sought.
Threshold
Adjusts the level of dithering
noise that is ignored. The ‘Auto’
button attempts to choose a
suitable value automatically, but
the level can also be adjusted
manually using the slider or
arrow buttons. The best value
is of course a compromise
between capturing all the ‘real’
screen changes whilst ignoring
the (almost invisible) dithering
noise. A good way to choose
the value is to watch the
Display Activity indicator for a
static screen. If the Threshold
is too low, the Display Activity
will be a high percentage while
nothing is really changing. If
the Threshold is too high, the
Display Activity will be very
low (or zero) but some real
changes in the screen may be
missed.