Black Box ACS235A - Manual (Page 31)

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SERVSWITCH™ BRAND FIBER KVM EXTENDERS
5.1.1 CPU
The ACS235A Extender supports IBM PC compatible desktop CPUs; it does not
support laptops. A CPU must have these kinds of interfaces to work fully with the
ACS235A Extender:
• Video: VGA, SVGA, XGA, or XGA-2. (Also supports most CPUs that output RGB.)
• Keyboard: IBM PS/2 style (6-pin mini-DIN). (With the included keyboard-port
adapter, will also support CPUs with PC/AT [5-pin DIN] keyboard ports.)
• Mouse: IBM PS/2 style (6-pin mini-DIN). (With the included mouse-port
adapter, will also support CPUs with RS-232 serial [DB9] mouse ports.)
• Parallel (optional): IBM PC style (Centronics compatible). This interface has
strict limitations; see Section 5.1.5.
The ACS236A Extender supports most Sun compatible CPUs that output VGA
video on an HD15 connector or legacy Sun Video on a 13W3 connector.
5.1.2 VGA M
ONITOR
The VGA red, green, and blue color signals are analog values in the range of 0 to
0.8 Vpp. The signals have no DC offset; this means that the black level meets
ground (that is, that the zero-signal [black] voltage level of the color leads is
equivalent to the voltage level of the color-ground leads). The horizontal and
vertical synchronization signals are TTL signals with various polarities, depending
on the selected monitor resolution (for example, text-only, 640 x 480, 800 x 600,
etc.). For transmission across the fiber cable, the SYNC signals are added to the
color-signals and separated again at the receiver.
CAUTION!
If you use a “Plug and Play” monitor, you will have to configure the
video settings manually.
5.1.3 RGB M
ONITOR OR
L
EGACY
S
UN
M
ONITOR
The RGB red, green, and blue color signals are analog values in the range of 0 to
0.8 Vpp. The composite (horizontal + vertical) synchronization signal is usually
added to the green signal, although some devices also add synchronization or
other information to the red and/or blue signals. Normally the color signals have a
DC offset, or at least the green/SYNC signal does; this means that DC voltage is
added to the lead so that even when there’s no color signal present (when the
screen is black), the color lead with the DC offset has higher voltage than the
ground lead. These signals must be clamped at the remote end, for linear
amplification in stages that follow.