Specifications

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CHAPTER 3: Installation
3.3.2 S YNCHRONIZED
S WITCH S YSTEMS FOR CPU S WITH UP TO E IGHT V IDEO O UTPUTS
Some CPUs and video cards can support a very large number of simultaneous
video outputs. CPUs with more than four video heads can’t be supported by a
single Multi-Head ServSwitch. But two Switches can be “synchronized” to handle
CPUs with as many as eight video heads.
Here’s how it works: When you switch to a different CPU channel, the Multi-
Head ServSwitch transmits the same switching command out of its RS-232 port.
Any other Multi-Head ServSwitch receiving this command will make the same
channel change. So you can connect a CPU’s additional video outputs to an
additional Switch, then interconnect the Switches’ RS-232 ports to create a
synchronized switching system that switches all video feeds coming from each CPU
at the same time.
(Note that each Switch in a synchronized system must be powered through a
power supply and not by the CPUs’ keyboard interfaces.)
Make sure that your “master” Multi-Head ServSwitch—the chassis that your
keyboard and mouse will be attached to—is unplugged and powered down. If
possible, turn off and unplug all of the devices that you want to attach to this
Switch. (If you have to “hot-plug” any powered computers into your Switch system,
see Section 5.8.)
Connect your primary user equipment (your keyboard, your PS/2 mouse, and
the first four of your monitors) to the appropriate “control port” connectors on
the master Switch’s rear panel. If you have had to place the Switch farther from the
user equipment than the equipment’s native cables will reach—up to an additional
distance of 30 ft. (9 m)—you can plug the native cables into Premium KVM User
Cable. If you need to place your user equipment farther away than that, please call
Black Box Tech Support for help determining your best extension options.
Attach all other monitors you’ll be using to the control-port video connector on
the rear panel of another Switch. As with your primary user equipment, use video-
extension cable or Premium KVM User Cable to cross gaps up to 30 ft. (9 m).
Connect this secondary Switch to your master Switch with DB15 cable. If your
CPUs don’t output more than eight video feeds, so that you only need to
synchronize these two Switches, you can use a special male-to-male DB15
synchronization cable (available on a quote basis; see Section A.3 of the Appendix
for a pinout). But if your CPUs output nine or more video feeds, you’ll need to use
pass-through, multi-drop, or preferably one-to-many DB15 cabling to interconnect
three or more Switches; call Black Box Tech Support to discuss your application.