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4-to-1 Keyboard & Mouse Switch
Control 4 PC’s Using one Keyboard and Mouse
UMA1017 Rev. C

IInnttrroodduuccttiioonn
“4-to-1”
eliminating the need for a separate mouse and keyboard for each PC.
allows one keyboard and mouse to control 4 different PC’s
Upon power up the
keyboard connected to it, and also emulate and present a fully functioning
keyboard and mouse to each connected PC
The unit draws power from the connected PC’s and no power supply is needed
(though there is a connector for external power). The external power supply is
only needed if a special keyboard or mouse with high power requirement is
used.
There are 2 ways the
through the buttons located on the front panel, and second via hot-key sequence
from the keyboard.
The unit supports 2-button, 3-button, and scroll mice.
When the
selected by default.
There are two different types of LEDs on the front panel. When the LED labeled
ON is illuminated then, the PC attached to that port is powered on. When the
LED labeled SEL is illuminated, then the PC attached to that port is currently
being controlled by the keyboard and mouse.
“4-to-1”
“4-to-1”
“4-to-1”
is powered up or reset, the PC that was last selected will be
will locate and identify the type of mouse and
can switch from one PC to another. First
Supported Systems and Peripherals
• All PC compatible systems and notebooks
• Standard PS/2 and AT Keyboards (Legacy AT keyboards may require
connector adapters)
• Standard (2-button) and wheel (3-button) (e.g. Microsoft Intellimouse)
mice. 4-button mice are not supported.
Features
• No Power Supply needed
• Reliable, Rugged, and easy to use
• Quick and seamless switching between PC’s
• LED indicators of PC power status and PC selected
• Comprehensive PS/2 protocol emulation for keyboard and mouse for
all PC’s at all times
• Hot-swapping capabilities of the PC’s and the devices
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• Returns to last selected PC after power off or reset
• Designed and manufactured in the USA
SSeettuupp
1. Use special “Y” input cables (ordered separately) to connect the PCs to the
Switch. The black end connects to the Switch. The purple connector, of the
“Y” cable, plugs into the keyboard port on PC #1 and the green connector
plugs into the mouse port of PC (it is best to turn off all PC’s when you are
hooking them to the 4-to-1).
2. Connect a mouse and a keyboard to the ports of the Switch.
3. Turn the PC’s on
4. The keyboard and mouse may now be treated as a keyboard and mouse
connected directly to the PC that is selected through the unit.
FIGURE 1
OOppeerraattiioonn
The keyboard and mouse will function no differently than if the keyboard and
mouse were connected directly to the PC.
“4-to-1”
connector functions and the Y-input cable
Switching
The first way to switch between the PC’s is to simply press the button for the
desired PC on the front panel of the Switch.
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The second way to switch is through a hot-key combination from the keyboard.
The hot-key combination is as follows.
Press and release: “Scroll Lock”
Press and release: “Scroll Lock”
Press and release: “1” or “2” or “3” or “4”
“4-to-1”
The
corresponding to the number pressed.
There is a 2 second timeout between each hot key. This means that if the
second Scroll Lock is not pressed within 2 seconds of the release of the first
Scroll Lock, the sequence will be aborted and will not switch. The same
situation applies to the number pressed after the release of the second Scroll
Lock.
will now switch to the PC connected to the port
Hot Swapping Mice and Keyboards
Hot swapping is not recommended but may be successfully performed. You may
unplug the mouse and/or the keyboard while the switch is powered up and PC’s
are connected and powered on. You may then plug in the same keyboard/mouse
or a different keyboard/mouse and the switch will recognize the new
keyboard/mouse and initialize it. The PC’s will not know the difference. The
only restriction to this is the following. The mouse you plug back in must be the
same type of mouse as was plugged in when the switch was first powered up. If
the original mouse was a 3-button mouse then you must plug in a 3-button
mouse. You may not plug in a 2-button mouse. If the original mouse was a 2button mouse then you may plug in a 2-button mouse or a 3-button mouse.
Hot Swapping PC’s
You may hot swap a PC while the
has been turned off. After the PC has been turned off, unplug the keyboard and
mouse connectors of the “Y” cable then plug them into the PC you wish to insert
into the
detect it and set it up accordingly.
“4-to-1”
setup. Then power on the new PC and the
“4-to-1”
is powered up only after that PC
“4-to-1”
will
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TTrroouubblleesshhoooottiinngg
Symptom Possible Cause(s)
Keyboard locks up
Mouse locks up
Power LED(s) not on
Selected LED(s) not on
1. Check PS2 cable and connection
2. Keyboard is unplugged
3. Keyboard needs to be unplugged and re-plugged in
4. Press Reset button on the rear of 4-to-1
1. Check PS2 cable and connection
2. Mouse is unplugged
3. Mouse needs to be unplugged and re-plugged in
4. Press Reset button on the rear of 4-to-1
1. PC may not be powered up
2. Check PS2 cable and connection
1.
“4-to-1”
has no power (all cpu’s are off)
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Product Designed and Made in the USA
© Copyright 2011. Hall Research, Inc.
All rights reserved.
CUSTOMER
SUPPORT
INFORMATION
Order toll-free in the U.S. 800-959-6439
FREE technical support, Call 714-641-6607 or fax 714-641-6698
Mail order: Hall Research, 1163 Warner Ave, Tustin, CA 92780
Web site: www.hallresearch.com • E-mail: info@ hallresearch.com