Black Box Switch KV6104SA User Manual

JULY 1998  
KV6104SA  
KV6108SA  
KV6112FA  
KV6116FA  
Customer Support Information:  
For FREE Technical Support 24 hours a day, 7 days a week, call 724-746-5500.  
Address: 1000 Park Dr., Lawrence, PA 15055-1018 • Phone: 724-746-5500 • Fax: 724-746-0746  
© Copyright 1998. Black Box Corporation. All rights reserved.  
 
THE SERVSWITCH™ FAMILY  
TM  
Welcome to the ServSwitch Family!  
®
Thank you for purchasing a BLACK BOX ServSwitch Brand KVM switch! We  
appreciate your business, and we think you’ll appreciate the many ways that your  
new ServSwitch keyboard/video/mouse switch will save you money, time, and  
effort.  
That’s because our ServSwitch family is all about breaking away from the  
traditional, expensive model of computer management. You know, the one-size-  
fits-all-even-if-it-doesn’t model that says, “One computer gets one user station, no  
more, no less.” Why not a single user station (monitor, keyboard, and mouse) for  
multiple computers—even computers of different platforms? Why not a pair of  
user stations, each of which can control multiple computers? Why not multiple  
user stations for the same computer?  
With our ServSwitch products, there’s no reason why not. We carry a broad line  
of robust solutions for all these applications. Do you have just two PCs, and need  
an economical alternative to keeping two monitors, keyboards, and mice on your  
®
desk? Or do you need to share dozens of computers, including a mix of IBM PC,  
®
®
®
®
®
RS/6000 , Apple Macintosh , Sun Microsystems , and SGI compatibles among  
multiple users with different access levels? Does your switch have to sit solidly on a  
worktable and use regular everyday cables? Or does it have to be mounted in an  
equipment rack and use convenient many-to-one cables? No matter how large or  
small your setup is, no matter how simple or how complex, we’re confident we  
have a ServSwitch system that’s just right for you.  
The ServSwitch family from Black Box—the one-stop answer for all your  
KVM-switching needs!  
*
This manual will tell you all about your new ServSwitch Duo unit, including  
how to install, operate, and troubleshoot it. For an introduction to the ServSwitch  
Duo, see Chapter 2. The ServSwitch Duo product codes covered in this manual  
are:  
KV6104SA  
KV6108SA  
KV6112FA  
KV6116FA  
This manual also includes information about the Remote-Control Module  
accessory, whose product code is:  
KV6REM  
1
 
SERVSWITCH DUO™  
TRADEMARKS USED IN THIS MANUAL  
BLACK BOX and the  
logo are registered trademarks, ServSwitch  
and ServSwitch Duo are trademarks of Black Box Corporation.  
Apple and Macintosh are registered trademarks of Apple Computer, Inc.  
Compaq is a registered trademark of Compaq Computer Corporation.  
Gateway 2000 is a registered trademark of Gateway 2000 Corporation.  
Hewlett-Packard is a registered trademark of Hewlett-Packard.  
IBM, PC/AT, PS/2, RS/6000, and ThinkPad are registered trademarks, and  
PC/XT is a trademark, of IBM Corporation.  
Logitech, MouseMan+, and Pilot Mouse+ are trademarks of Logitech, Inc.  
Microsoft and Windows are registered trademarks, and IntelliMouse is a  
trademark, of Microsoft Corporation.  
SGI is a registered trademark of Silicon Graphics, Inc.  
Sun Microsystems is a registered trademark of Sun Microsystems, Inc.  
Any other trademarks mentioned in this manual are acknowledged to be the property of the  
trademark owners.  
2
 
FCC/IC STATEMENTS  
FEDERAL COMMUNICATIONS COMMISSION  
AND  
INDUSTRY CANADA  
RADIO FREQUENCY INTERFERENCE STATEMENTS  
This equipment generates, uses, and can radiate radio frequency energy and if not  
installed and used properly, that is, in strict accordance with the manufacturer’s  
instructions, may cause interference to radio communication. It has been tested  
and found to comply with the limits for a Class A computing device in accordance  
with the specifications in Subpart J of Part 15 of FCC rules, which are designed to  
provide reasonable protection against such interference when the equipment is  
operated in a commercial environment. Operation of this equipment in a  
residential area is likely to cause interference, in which case the user at his own  
expense will be required to take whatever measures may be necessary to correct  
the interference.  
Changes or modifications not expressly approved by the party responsible for  
compliance could void the user’s authority to operate the equipment.  
Shielded cables must be used with this equipment to maintain compliance with  
radio frequency energy emission regulations and ensure a suitably high level of  
immunity to electromagnetic disturbances.  
This digital apparatus does not exceed the Class A limits for radio noise emission from  
digital apparatus set out in the Radio Interference Regulation of Industry Canada.  
Le présent appareil numérique n’émet pas de bruits radioélectriques dépassant les limites  
applicables aux appareils numériques de la classe A prescrites dans le Règlement sur le  
brouillage radioélectrique publié par Industrie Canada.  
3
 
SERVSWITCH DUO™  
EUROPEAN UNION DECLARATION OF CONFORMITY  
This equipment has been tested and found to comply with the limits for a class B  
computing device in accordance with the specifications in the European standard  
EN55022. These limits are designed to provide reasonable protection against  
harmful interference. This equipment generates, uses and can radiate radio  
frequency energy and if not installed and used in accordance with the instructions  
may cause harmful interference to radio or television reception. However, there is  
no guarantee that harmful interference will not occur in a particular installation. If  
this equipment does cause interference to radio or television reception, which can  
be determined by turning the equipment on and off, the user is encouraged to  
correct the interference with one or more of the following measures:  
(a) Reorient or relocate the receiving antenna.  
(b) Increase the separation between the equipment and the receiver.  
(c) Connect the equipment to an outlet on a circuit different from that to which  
the receiver is connected.  
(d)Consult the supplier or an experienced radio/TV technician for help.  
Shielded cables must be used with this equipment to maintain compliance with  
radio frequency energy emission regulations and ensure a suitably high level of  
immunity to electromagnetic disturbances.  
4
 
NOM STATEMENT  
NORMAS OFICIALES MEXICANAS (NOM)  
ELECTRICAL SAFETY STATEMENT  
INSTRUCCIONES DE SEGURIDAD  
1. Todas las instrucciones de seguridad y operación deberán ser leídas antes  
de que el aparato eléctrico sea operado.  
2. Las instrucciones de seguridad y operación deberán ser guardadas para  
referencia futura.  
3. Todas las advertencias en el aparato eléctrico y en sus instrucciones  
de operación deben ser respetadas.  
4. Todas las instrucciones de operación y uso deben ser seguidas.  
5. El aparato eléctrico no deberá ser usado cerca del agua—por ejemplo,  
cerca de la tina de baño, lavabo, sótano mojado o cerca de una alberca, etc..  
6. El aparato eléctrico debe ser usado únicamente con carritos o pedestales  
que sean recomendados por el fabricante.  
7. El aparato eléctrico debe ser montado a la pared o al techo sólo como sea  
recomendado por el fabricante.  
8. Servicio—El usuario no debe intentar dar servicio al equipo eléctrico más allá  
a lo descrito en las instrucciones de operación. Todo otro servicio deberá ser  
referido a personal de servicio calificado.  
9. El aparato eléctrico debe ser situado de tal manera que su posición no  
interfiera su uso. La colocación del aparato eléctrico sobre una cama, sofá,  
alfombra o superficie similar puede bloquea la ventilación, no se debe colocar  
en libreros o gabinetes que impidan el flujo de aire por los orificios de  
ventilación.  
10. El equipo eléctrico deber ser situado fuera del alcance de fuentes de calor  
como radiadores, registros de calor, estufas u otros aparatos (incluyendo  
amplificadores) que producen calor.  
11. El aparato eléctrico deberá ser connectado a una fuente de poder sólo del  
tipo descrito en el instructivo de operación, o como se indique en el aparato.  
5
 
SERVSWITCH DUO™  
12. Precaución debe ser tomada de tal manera que la tierra fisica y la polarización  
del equipo no sea eliminada.  
13. Los cables de la fuente de poder deben ser guiados de tal manera que no  
sean pisados ni pellizcados por objetos colocados sobre o contra ellos,  
poniendo particular atención a los contactos y receptáculos donde salen  
del aparato.  
14. El equipo eléctrico debe ser limpiado únicamente de acuerdo a las  
recomendaciones del fabricante.  
15. En caso de existir, una antena externa deberá ser localizada lejos de las lineas  
de energia.  
16. El cable de corriente deberá ser desconectado del cuando el equipo no sea  
usado por un largo periodo de tiempo.  
17. Cuidado debe ser tomado de tal manera que objectos liquidos no sean  
derramados sobre la cubierta u orificios de ventilación.  
18. Servicio por personal calificado deberá ser provisto cuando:  
A: El cable de poder o el contacto ha sido dañado; u  
B: Objectos han caído o líquido ha sido derramado dentro del aparato; o  
C: El aparato ha sido expuesto a la lluvia; o  
D: El aparato parece no operar normalmente o muestra un cambio en su  
desempeño; o  
E: El aparato ha sido tirado o su cubierta ha sido dañada.  
6
 
TABLE OF CONTENTS  
Contents  
Chapter  
Page  
1. Specifications ............................................................................................... 9  
2. Introduction ............................................................................................... 11  
2.1 Features and Benefits of the ServSwitch Duo ................................... 11  
2.2 The Complete ServSwitch Duo Package ............................................ 12  
2.3 The ServSwitch Duo Illustrated ......................................................... 13  
2.4 Safety Concerns ................................................................................... 15  
3. Installation .................................................................................................. 16  
3.1 What You Will Need ............................................................................ 16  
3.2 Rackmounting the ServSwitch Duo (Optional) ................................ 17  
3.3 Connecting Your Devices ................................................................... 17  
3.4 Connecting Power ............................................................................... 19  
4. Configuration ............................................................................................. 20  
4.1 Configuring Your PCs ......................................................................... 20  
4.2 Configuring the ServSwitch Duo ....................................................... 20  
4.2.1 Entering Configuration Mode ............................................... 20  
4.2.2 Setting the Screen-Saver Timeout ......................................... 21  
4.2.3 Autoscanning: Setting the Scan Mode and Pause Time ....... 22  
4.2.4 Setting the Switchover Timeout ............................................. 23  
4.2.5 Setting Mouse-Mode Reporting and Mouse Switching ........ 23  
4.2.6 Setting the Hotkey Sequence ................................................. 25  
4.2.7 Viewing the Firmware Revision, Restoring Mouse  
Function, or Resetting to Factory Defaults ......................... 26  
4.2.8 Setting the Appearance of the On-Screen Display ............... 26  
4.2.9 Setting the Password ............................................................... 27  
4.2.10 Exiting Configuration Mode .................................................. 27  
7
 
SERVSWITCH DUO™  
Contents (continued)  
Chapter  
Page  
5. Operation ................................................................................................... 28  
5.1 Power Status ...................................................................................... 28  
5.2 The Status LEDs ............................................................................... 28  
5.3 The Front-Panel Pushbuttons and the Remote-Control Module .. 28  
5.4 The Status Display ............................................................................ 30  
5.5 Using the Dual Control Ports (A and B) ........................................ 31  
5.6 Things to Keep in Mind About the Keyboards and Mice .............. 31  
5.7 Keyboard Control: Hotkey Commands ........................................... 32  
5.8 On-Screen Menu Control ................................................................ 35  
5.8.1 Adding a Computer to the Menu List ................................... 36  
5.8.2 Deleting a Computer from the Menu List ............................ 36  
5.8.3 Editing a Computer on the Menu List .................................. 36  
5.8.4 Selecting a Computer on the Menu List ............................... 37  
5.8.5 Exiting the Menu .................................................................... 37  
5.8.6 Configuring the Menu ............................................................ 37  
5.8.7 Summary of Keys Used by the Menu and Their Functions .. 37  
5.9 Mouse Control .................................................................................. 38  
5.10 Re-Enabling a Disconnected PS/2 Mouse ...................................... 38  
5.11 Hot-Plugging Devices Into the ServSwitch Duo and  
Re-Enabling Disconnected CPU PS/2 Mouse Ports .................... 38  
5.12 RS-232 Control .................................................................................. 40  
5.13 Cascading ServSwitch Duos ............................................................. 40  
6. Troubleshooting ........................................................................................ 43  
6.1 Things to Try ....................................................................................... 43  
6.2 Calling Black Box ................................................................................ 46  
6.3 Shipping and Packaging ..................................................................... 46  
Appendix: Cable and Connector Guidelines .................................................. 47  
A.1 Cabling: Keyboard, Monitor, and Mouse to ServSwitch Duo ........... 47  
A.2 Cabling: ServSwitch Duo to PCs ......................................................... 47  
A.3 The Expansion Port ............................................................................ 49  
8
 
CHAPTER 1: Specifications  
1. Specifications  
CE (EN55022 Class B); FCC Part 15 Subpart J Class A,  
IC Class/ classe A  
Compliance —  
Standards —  
Interfaces —  
VGA, SVGA, XGA, or XGA-2 video  
Video: VGA;  
Keyboard and mouse: IBM PS/2 compatible;  
Expansion port: Proprietary variant of TIA RS-232  
Resolution —  
Protocol —  
Up to 1600 x 1200 noninterlaced at up to 100 Hz  
RS-232: Asynchronous  
Data Format —  
Data Rate —  
Flow Control —  
RS-232: 8 data bits, no parity, 1 stop bit  
RS-232: 1200 bps  
RS-232: None  
Maximum  
Distance —  
10 m (32.8 ft.) to any attached keyboard, monitor, and  
mouse;  
30 m (98.4 ft.) to any attached CPU or cascaded  
ServSwitch Duo unit;  
40 m (131.2 ft.) to an attached ServSwitch Duo Extender  
across Premium Extender Cable  
User Controls —  
Indicators —  
Keyboard commands;  
Mouse-click functions;  
(2) Front-mounted pushbuttons;  
On-screen menu  
All front-mounted:  
KV6104SA, KV6108SA: Single 7-segment status display  
with activity LED;  
KV6112FA, KV6116FA: Dual 7-segment status display  
with activity LED;  
KV6104SA: (4) Port LEDs;  
KV6108SA: (8) Port LEDs;  
KV6112FA: (12) Port LEDs;  
KV6116FA: (16) Port LEDs  
9
 
SERVSWITCH DUO™  
Connectors —  
All rear-mounted:  
(2) HD15 female for monitor attachment;  
(4) 6-pin mini-DIN female for keyboard and mouse  
attachment;  
(1) DB15 female for RS-232;  
(1) Barrel jack for power;  
For each computer port, a set of (1) HD15 female (for  
video attachment) and (2) 6-pin mini-DIN female  
(for keyboard-port and mouse-port attachment):  
KV6104SA: (4);  
KV6108SA: (8);  
KV6112FA: (12);  
KV6116FA: (16)  
Power —  
MTBF —  
Input: 100 to 240 VAC at 50 to 60 Hz from utility-power  
outlet, through detachable power cord and IEC 320  
male inlet, to external transformer;  
Output: 5 VDC at up to 1 A from transformer to Switch;  
Consumption: 5 watts maximum  
500,000 hours (based on the historical reliability of  
similarly designed and manufactured products)  
Maximum  
Altitude —  
10,000 ft. (3048 m)  
Temperature  
Tolerance —  
32 to 104˚ F (0 to 40˚ C)  
Humidity  
Tolerance —  
5 to 60% noncondensing  
Steel and aluminum  
Enclosure —  
Size —  
KV6104SA, KV6108SA:  
1.8" (1U) H x 17.3"W x 8.7"D (4.4 x 43.9 x 22.1 cm);  
KV6112FA, KV6116FA:  
3.5" (2U) H x 17.3"W x 8.7"D (8.9 x 43.9 x 22.1 cm)  
Weight —  
KV6104SA: 4.8 lb. (2.2 kg);  
KV6108SA: 5.1 lb. (2.3 kg);  
KV6112FA: 6.8 lb. (3.1 kg);  
KV6116FA: 7 lb. (3.2 kg)  
10  
 
CHAPTER 2: Introductiom  
2. Introduction  
The ServSwitch Duo is a high-performance keyboard-, monitor-, and mouse-  
®
sharing device that supports a wide range of IBM PC compatible hardware and  
software platforms.  
2.1 Features and Benefits of the ServSwitch Duo  
Here are some of the useful features of the ServSwitch Duo and some of the ways  
those features benefit you:  
• Control multiple PCs from a local and remote keyboard, monitor, and mouse.  
• Use the on-screen menu to assign names to computers and select channels on  
that basis.  
®
®
• Mixed PC/AT and PS/2 keyboards and PS/2 and RS-232 mice supported  
as standard.  
• Can be cascaded to control hundreds of CPUs.  
• High-resolution circuitry ensures the best possible video, even over extended  
distances.  
• Password security prevents unauthorised use.  
• Optional Remote-Control Module for convenient operation.  
• Channel switching through on-screen display, front-panel pushbutton,  
keyboard hotkey sequence, or 3-button mouse.  
• Automatically restores keyboard and mouse states when channel is changed.  
• Can be switched remotely through its RS-232 serial port.  
• Supports high-bandwidth monitors at resolutions up to 1600 x 1200 pixels.  
• Supports keyboard modes 1, 2, and 3, as well as both “prompt” and “stream”  
mouse modes, for maximum compatibility.  
• Includes screen-blank, autoscan, and variable-hotkey options.  
• Confirmation of selected ports on local and cascaded Switches.  
®
• Support for Microsoft IntelliMouse™.  
• Mouse-restoration functions to enable hot-plugging of certain systems.  
11  
 
SERVSWITCH DUO™  
2.2 The Complete ServSwitch Duo Package  
You should have received these components with your ServSwitch Duo:  
• The ServSwitch Duo itself.  
• A power-supply transformer and output cord.  
• A power-supply input cord suitable for your country or region.  
• (1) PS/2 to serial mouse adapter and (1) PS/2 to AT keyboard adapter for  
every (4) CPU ports on a given Switch; in other words, the 4-port Switch comes  
with one mouse adapter and one keyboard adapter, the 8-port Switch comes  
with two mouse adapters and two keyboard adapters, and so on.  
• (6) Stick-on self-adhesive rubber feet (for desktop applications).  
• (2) Mounting brackets and, depending on the Switch’s size, (4) or (6) screws  
(for mounting the Switch in a 19" rack).  
• This manual.  
If you didn’t receive everything, or if anything arrived damaged, contact Black Box  
right away.  
12  
 
CHAPTER 2: Introduction  
2.3 The ServSwitch Duo Illustrated  
Attachment  
Red LEDs  
show currently  
active control  
port (A or B)  
Key for  
points for  
Display shows  
changing  
rackmount  
bracket  
status and  
BLACK BOX  
channels and  
entering  
configuration  
mouse/keyboard  
data activity  
mode  
ACTIVE USER  
A
B
1
2
3
4
5
6
7
8
SELECT  
O
SCAN  
AUT  
Key for  
selecting  
autoscan  
Green LEDs show  
the ON/OFF status  
of connected CPUs  
(LEDs 5 through 8  
are present on  
Both keys together  
used to lock the  
Switch or reset  
8-port model only)  
keyboards and mice  
Fig. 2-1. The front and side panels of the 4- and 8-port ServSwitch Duo  
models (KV6104SA and KV6108SA).  
CPU-port video connectors  
Control ports Control-port monitor CPU ports 1 through 8 (ports 5 through 8  
Expansion port for Remote-Control Module and RS-232 control  
A and B connectors are present on 8-port model only)  
5V  
1A  
B
A
8
7
6
5
4
3
2
1
Power  
connector  
Control-port keyboard  
connectors  
CPU-port mouse  
connectors  
CPU-port keyboard  
connectors  
Control-port  
mouse connectors  
Fig. 2-2. The rear panel of the 4- and 8-port ServSwitch Duo models.  
Fig. 2-3. The Remote-Control Module (KV6REM), an optional accessory  
for the 4- and 8-port Switch models.  
13  
 
SERVSWITCH DUO™  
LED shows the  
power status  
of the Switch  
Attachment  
points for  
Red LEDs  
show currently  
active control  
port (A or B)  
rackmount  
Key for  
bracket  
Display shows  
status and  
mouse/keyboard  
data activity  
BLACK BOX  
changing  
channels and  
entering  
configuration  
mode  
PWR  
ACTIVE USER  
A
B
12 13 14 15 16  
1
10 1  
1
2
3
4
5
6
7
8
9
SELECT  
O
SCAN  
AUT  
Green LEDs show  
the ON/OFF status  
of connected CPUs  
(LEDs 13 through 16  
are present on  
Key for  
selecting  
autoscan  
Both keys together  
used to lock the  
Switch or reset  
16-port model only)  
keyboards and mice  
Fig. 2-4. The front and side panels of the 12- and 16-port ServSwitch Duo  
models (KV6112FA and KV6116FA).  
CPU-port video connectors  
Expansion port for Remote-Control Module and RS-232 control  
CPU ports 1 through 16 (ports 13 through 16  
are present on 16-port model only)  
Control-port monitor  
connectors  
16  
15  
7
14  
6
13  
5
12  
4
11  
3
10  
2
9
1
5V  
1A  
B
A
8
Power  
connector  
Control-port keyboard  
connectors  
CPU-port mouse  
connectors  
CPU-port keyboard  
connectors  
Control ports  
A and B  
Control-port  
mouse connectors  
Fig. 2-5. The rear panel of the 12- and 16-port ServSwitch Duo models.  
14  
 
CHAPTER 2: Introduction  
2.4 Safety Concerns  
As you prepare to install the ServSwitch Duo, please keep these things in mind:  
• The Switch is for use in dry, oil-free indoor environments only.  
• Warning: The Switch’s power adapter contains no user-serviceable parts, but it  
does contain parts capable of delivering hazardous electric shocks—do not  
attempt to dismantle it!  
• Plug the power adapter into a socket outlet close to the Switch.  
• Do not use the Switch’s power adapter if its case becomes damaged, cracked,  
or broken, or if you suspect that it is not operating properly.  
• If the Switch’s power adapter stops working, replace it with a manufacturer-  
approved adapter of the same type only.  
15  
 
SERVSWITCH DUO™  
3. Installation  
3.1 What You Will Need  
You’ll need these things to be in place before you can install your ServSwitch Duo:  
• Cables to connect the ServSwitch Duo to the keyboard, video, and mouse ports  
of each of your PCs. Cable specifications are given in Appendix A. (You do not  
need to connect a mouse cable if you are not using the mouse).  
• A monitor with a standard VGA/SVGA (HD15) connector that will work when  
connected directly to each of your PCs. The ServSwitch Duo supports low- and  
high-resolution monitors.  
• A standard PC/AT or PS/2 style keyboard. If you are using an AT keyboard  
with a 5-pin DIN connector, you may connect it to the ServSwitch Duo using  
a standard AT to PS/2 keyboard adapter (one of these is included for every  
fourCPU ports your Switch has).  
®
• A PS/2 style two- or three-button Microsoft or Logitech compatible mouse or  
a Microsoft IntelliMouse compatible mouse. If you want to use the mouse to  
switch channels on the ServSwitch Duo, you will need a three-button mouse or  
an IntelliMouse. (The Switch supports other “Internet mice” compatible with  
the IntelliMouse—fitted with a wheel or other scrolling control, and  
sometimes additional buttons—including the Logitech Pilot Mouse+ ,  
Logitech MouseMan+ , Genius NetMouse and Genius NetMouse Pro )  
All of the mouse connections from ServSwitch Duo to the attached PCs  
support either a PS/2 or an RS-232 mouse. The Switch automatically converts  
PS/2 mouse commands to RS-232 serial-mouse commands. You can use a  
serial mouse if you attach it to the Switch through an appropriate adapter,  
as described in the Appendix (one of these adapters is included for every  
fourCPU ports your Switch has). The Switch will operate without a mouse  
connected if you do not wish to use one.  
• A suitable mouse driver for your PCs. Supported types are:  
- PS/2 or RS-232 two-button mouse driver by any manufacturer.  
- Microsoft mouse drivers, including those for the IntelliMouse.  
- Logitech mouse drivers, including those for two-button, three-button, and  
wheel mice.  
16  
 
CHAPTER 3: Installation  
3.2 Rackmounting the ServSwitch Duo (Optional)  
The ServSwitch Duo has been designed to be used either on a desktop or mounted  
in a 19" rack. If the ServSwitch Duo is to be used on a desktop, you will need to  
stick the included self-adhesive rubber feet to the underside of the Switch. If the  
ServSwitch Duo is to be mounted in a 19" rack, you will need to fit the included  
rackmount brackets to the sides of the Switch using the included screws.  
3.3 Connecting Your Devices  
Make sure that your single or master ServSwitch Duo and (if possible) all the  
devices you want to attach to it are turned off and unplugged. (If you have to “hot-  
plug” any powered computers into the Switch, see Section 5.11.) Connect one or  
two sets of shared user equipment (keyboard, PS/2 mouse, and monitor) to the  
appropriate connectors on the Switch’s rear panel (either or both of control  
ports A and B; see Figure 2-2 or 2-5 in Section 2.3). If you are connecting two sets  
of keyboards, monitors, and mice, you don’t need to use the same brands or types  
of devices on each control port: For example, you can use a two-button PS/2  
mouse on one port and a Microsoft IntelliMouse on the other. If you have had to  
place the Switch farther from the user equipment than the equipment’s native  
cables will reach, you can plug the native cables into ServSwitch Duo User-  
Extension Cable (our product code EHN409), which comes in 10-foot (3-m) and  
30-foot (9.1-m) lengths. If you need to run even farther, you can use a ServSwitch  
Duo Extender (our product code KV6EXT) with 130-ft. (39.6-m) Premium  
Extender Cable (our product code KV6100) to connect the Switch to the  
keyboard, mouse, and monitor. (For more information about the Extender,  
see its manual.)  
Both the User-Extension Cable and Premium Extender Cable, as well as the  
CPU-Extension Cable discussed in the next paragraph, are built to the special  
three-in-one design shown in Figure 3-1 on the next page. The central coaxial  
video strand of each cable is molded to the keyboard and mouse strands on either  
side, and the ends of its video strand are one inch (2.5 cm) longer than the ends of  
the other strands, so that the weight of the composite cable can be borne by the  
video connector’s screwlocks. To help you tell the otherwise identical keyboard  
and mouse strands apart, the keyboard strand is labeled “K” and colored orange,  
while the mouse strand is labeled “M” and colored green.  
17  
 
SERVSWITCH DUO™  
6-Pin  
mini-DIN  
6-Pin  
mini-DIN  
HD15  
10"  
(25.4  
cm)  
9"  
(22.9  
cm)  
Cross-section:  
Central  
video  
strand  
Keyboard and mouse  
strands molded to sides  
Figure 3-1. The ServSwitch Duo cables.  
Next, connect each computer or (in cascaded systems) subsidiary ServSwitch  
Duo to your single/master Switch. One way to do this is to run separate male-to-  
male keyboard-, mouse-, and video-extension cables from the appropriate CPU-  
port connectors on the single/master Switch to (a) the keyboard, mouse, and  
video ports respectively of the computer or (b) the keyboard, mouse, and monitor  
connectors respectively of control port A or B of the subsidiary Switch. (Any  
unused CPU-port or control-port connectors on the single/master Switch can be  
left vacant.) Alternatively, instead of three separate cables, you can use our three-  
in-one ServSwitch Duo CPU-Extension Cable (our product code EHN408), whose  
design is shown in Figure 3-1 above. This cable is available in 5-foot (1.5-m),  
10-foot (3-m), 30-foot (10-m), 50-ft. (15-m), and 100-ft. (30-m) lengths.  
18  
 
CHAPTER 3: Installation  
To connect computers with serial mouse ports and PC/AT style keyboard ports,  
you’ll need adapters, as shown in Figure 3-2 below . Refer to the Appendix for  
cable guidelines.  
PS/2 to Serial Mouse  
PS/2 style kbd/mouse cable  
Adapter; to computer’s  
serial mouse port (DB9)  
(one included for each  
four CPU ports)  
To Switch’s CPU-port  
mouse connector  
(6-pin mini-DIN)  
PS/2 to PC/AT Keyboard  
Adapter; to computer’s  
AT compatible keyboard  
port (5-pin DIN)  
(one included for each  
four CPU ports)  
PS/2 style kbd/mouse cable  
To Switch’s CPU-port  
keyboard connector  
(6-pin mini-DIN)  
Figure 3-2. Using adapters to connect computers with serial mouse ports or  
PC/AT keyboard ports.  
3.4 Connecting Power  
Once you’ve installed your ServSwitch Duo and attached your equipment to it, you  
can plug its power supply into the jack on the back of the Switch, then attach the  
input cord to the power-supply transformer’s IEC 320 inlet, then plug the input  
cord into utility (mains) power. (Always apply power to the ServSwitch Duo first,  
then power on the monitor and each of the computers; if you power up the  
computers before the Switch, the computers might not recognize the presence  
of the mouse or keyboard.) The Switch should start operating immediately; it has  
no ON/OFF switch.  
19  
 
SERVSWITCH DUO™  
4. Configuration  
To configure your ServSwitch Duo system, you’ll need to configure first the  
attached PCs, as directed in Section 4.1, then the Switch itself, as directed in the  
rest of this chapter.  
IMPORTANT NOTE  
Throughout the rest of this manual, the [Enter] designation refers to the  
main “enter” or “carriage-return” key (often labeled “”) on the main  
section of the keyboard. Do not use the “Enter” key on the numeric  
keypad or the extra “Enter” key found on the main section of some  
specialized keyboards.  
4.1 Configuring your PCs  
Configure your PCs in the same way that you would if your keyboard, mouse and  
monitor were all connected directly to your PCs, but keep these things in mind:  
• The ServSwitch Duo emulates Microsoft compatible serial, IntelliMouse, and  
PS/2 mice, so make sure that your PC software is configured for a Microsoft  
mouse of the correct type. Refer to the list of supported drivers in Section 3.1.  
• The ServSwitch Duo supports VGA, SVGA, XGA, and XGA-2 type monitors,  
but does not support the automatic detection features available with some  
Plug-and-Play monitors and video cards. If you have this type of video card or  
monitor, you should select the video mode manually instead of relying on the  
automatic detection feature.  
4.2 Configuring the ServSwitch Duo  
The ServSwitch Duo comes from the factory preset to default configuration  
settings which are suitable for most applications. If you need to set the Switch  
differently, you can access its “configuration mode” to do so; once you do, the  
new settings are stored in the ServSwitch Duo’s EEPROM memory and are  
retained when the Switch is powered OFF.  
4.2.1 ENTERING CONFIGURATION MODE  
You can access the ServSwitch Duo’s configuration mode in either of two different  
ways: Use one method when you plug in and power up the Switch; use the other  
while the Switch is operating.  
• To enter configuration mode at power-up, make sure that the ServSwitch Duo  
and all attached PCs are turned OFF and unplugged. Hold down the SELECT  
20  
 
CHAPTER 4: Configuration  
key while you plug in the ServSwitch Duo; do not release SELECT until the  
ServSwitch Duo displays “C” to show that it is in configuration mode.  
• To enter configure mode while the ServSwitch Duo is running, hold down the  
SELECT key for 5 seconds until the front-panel display shows “C”.  
In configuration mode, you can change settings by typing a single-letter command  
(for a given feature), followed by a single-digit numeric argument (for how you  
want that feature to behave), followed by the [Enter] key. Press the [Esc] (escape)  
key to abort a setting change before you fully enter it. The ServSwitch Duo will  
remain in configuration mode until you type the letter “E” followed by [Enter] key.  
For example: To set the hotkey sequence to option #2 ([Ctrl] + [Shift] +  
command key), type [H][2][Enter] while the ServSwitch Duo is displaying “C”,  
then type [E][Enter] to exit configuration mode.  
The remaining sections of this chapter describe the Switch’s user-configurable  
settings.  
4.2.2 SETTING THE SCREEN-SAVER TIMEOUT  
The ServSwitch Duo has a programmable screen-saver function which will blank  
the display on both shared monitors after a certain time elapses with no activity on  
the shared keyboard or mouse of the active control port (or of either control port  
if the switchover timeout has expired—see Section 4.2.4). If a password has been  
set (see Section 4.2.9), the Switch will also lock itself when it activates the screen  
saver.  
The Switch’s front-panel display will flash while the Switch is in screen-saver  
mode. If the switch is locked, you will have to type in the password to unlock it and  
deactivate the screen saver; otherwise, simply typing at the keyboard or moving the  
mouse of the active control port—or at either control port if the switchover  
timeout has expired—will restore the blanked monitor display. Use the “B”  
command (type [B] [digit] [Enter]) to set how long the ServSwitch Duo waits for  
keyboard or mouse activity before activating the screen saver:  
• B1 = Screen saver disabled (default)  
• B2 = Screen saver is activated after 1 minute of inactivity  
• B3 = 2 minutes  
• B4 = 4 minutes  
• B5 = 8 minutes  
• B6 = 12 minutes  
• B7 = 16 minutes  
• B8 = 20 minutes  
21  
 
SERVSWITCH DUO™  
4.2.3 AUTOSCANNING: SETTING THE SCAN MODE AND PAUSE TIME  
The ServSwitch Duo begins autoscanning its CPU channels (that is, briefly  
displaying each channel’s video in turn) when you type in the hotkey sequence  
followed by the letter “A” (see Section 5.7). By default, the Switch only scans those  
channels that have a powered-up computer connected to them. But if you need the  
Switch to scan all of its channels, you can send it the [L][2] or [L][4] command.  
(In these settings, when the Switch scans a channel that has no computer attached,  
or a channel whose computer is off or just not outputting video, the shared  
monitor will display a blank screen.) Also, if you want the Switch to start  
autoscanning as soon as it powers up, instead of waiting for the “A” command, you  
can send it the [L][3] or [L][4] command.  
L1 ServSwitch Duo only scans active ports during autoscanning (default)  
L2 ServSwitch Duo scans every one of its ports during autoscanning  
CAUTION!  
Many modern monitors are fitted with automatic power-saver relays  
and will automatically blank their displays after a short time if the  
PC they’re communicating with becomes idle. If you are using such  
a monitor, you should not use the Switch’s L2 or L4 setting unless  
you can set the monitor’s power-saver timeout to an interval longer  
than the Switch’s autoscan pause time (see below), because if the  
monitor keeps going in and out of power-saver mode during  
autoscanning, the constant switching ON and OFF of your  
monitor’s relay will eventually damage your monitor.  
L3 ServSwitch Duo powers on in autoscan mode and scans active ports only  
L4 ServSwitch Duo powers on in autoscan mode and scans all ports  
While autoscanning, the Switch will pause at each channel to display that channel’s  
video signal for the duration of the currently selected autoscan-pause time:  
T1 During autoscan, the Switch pauses at each channel for 2 seconds (default)  
T2 5 seconds  
T3 7 seconds  
T4 10 seconds  
T5 15 seconds  
T6 20 seconds  
T7 30 seconds  
T8 60 seconds  
To get out of autoscan mode, simply select a fixed channel using the on-screen  
menu, the Switch’s SELECT button, the keyboard hotkeys, or the mouse.  
22  
 
CHAPTER 4: Configuration  
4.2.4 SETTING THE SWITCHOVER TIMEOUT  
To be able to control the ServSwitch Duo from either of two separate locations at  
any given time, you have to connect keyboards, monitors, and mice to both of the  
Switch’s control ports, A and B. The Switch sends the video from the currently  
selected computer to both monitors at the same time, but it will accept only one  
source of keyboard and mouse data at a time, so only one of the control ports at a  
time can be in active control. The other port is automatically disabled, although  
the video continues to be displayed. This port can be given keyboard and mouse  
control (that is, control can be “switched over”) when there has been no keyboard  
or mouse activity on the currently active control port for a certain period of time,  
called the “switchover timeout.” You can set the switchover timeout to any of seven  
intervals, from 2 seconds to 10 minutes, using the “S” command (type  
[S][digit][Enter]):  
S1 Keyboard and mouse control can be switched over from control port A to  
control port B, or vice versa, when the currently active port has been idle  
for 2 seconds (default)  
S2 5 seconds  
S3 10 seconds  
S4 30 seconds  
S5 1 minute  
S6 5 minutes  
S7 10 minutes  
4.2.5 SETTING MOUSE-MODE REPORTING AND MOUSE SWITCHING  
In the ServSwitch Duo’s factory-default state, you can use a three-button PS/2  
mouse or an IntelliMouse to cycle through the Switch’s CPU channels. To switch to  
the next channel, simply hold down the center or “wheel” button on the mouse,  
then press its left button. If you don’t want to use this feature—particularly if it’s  
going to conflict with mouse-controlled application functions—you can disable it  
by sending the [U][2], [U][3], or [U][5] command. If the third button on a  
three-button mouse is being used to switch the ServSwitch Duo, it won’t be  
available for use with PC software, although the wheel on an IntelliMouse can be  
used for both switching and software with no problems. For this reason, we’ve  
included the [U][1], [U][2], and [U][4] command options, which cause the  
ServSwitch Duo to report to the attached PCs that they are attached to a 2-button  
mouse. If you want to use all the functions of a 3-button mouse or IntelliMouse for  
your PC software, you should send the Switch the [U][3] or [U][5] command.  
23  
 
SERVSWITCH DUO™  
The ServSwitch Duo supports “Internet mice” that are compatible with the  
Microsoft IntelliMouse. These are fitted with a wheel or other type of scrolling  
control and sometimes have additional buttons. Examples are:  
• Microsoft IntelliMouse  
• Logitech Pilot Mouse+  
• Logitech MouseMan+  
• Genius NetMouse  
• Genius NetMouse Pro  
You can connect standard PS/2 mice and IntelliMouse compatible mice to  
control ports A and B in any combination. You can configure your CPUs using  
Microsoft PS/2 or IntelliMouse drivers in any combination as required.  
IntelliMouse features are supported on both PS/2 and RS-232 CPU connections.  
When you use PS/2 CPU connections, the ServSwitch Duo will automatically  
configure itself to the type of mouse requested by the driver. If you are using  
RS-232 CPU connections, you will need to send the [U][4] or [U][5] command to  
enable the IntelliMouse features.  
U1 Channels are mouse-switchable; the Switch reports “2-button mouse” to the  
attached PCs (default)  
U2 Channels are not mouse-switchable; the Switch reports “2-button mouse” to  
the attached PCs  
U3 Channels are not mouse-switchable; the Switch reports “3-button mouse” to  
the attached PCs  
U4 Channels are mouse-switchable; the Switch reports “IntelliMouse” to the  
attached PCs  
U5 Channels are not mouse-switchable; the Switch reports “IntelliMouse” to  
the attached PCs  
24  
 
CHAPTER 4: Configuration  
4.2.6 SETTING THE HOTKEY SEQUENCE  
You can access many of the ServSwitch Duo’s main functions (such as CPU-channel  
selection, autoscanning, and locking) by sending commands from the shared  
keyboard. Each command must start with a “hotkey sequence” (series of  
keystrokes) that alerts the Switch to interpret the keyboard data that follows it as a  
command. The default hotkey sequence is [Ctrl] and [Alt] pressed simultaneously.  
If any of the applications on computers attached to the Switch require this  
sequence to trigger important application-specific functions, you will have to  
change the Switch’s hotkey sequence with the “H” command (type  
[H][digit][Enter]).  
Alternative hotkey sequence #5 is particularly suitable for extended keyboards  
where additional keys can be programmed to act as combinations of other keys.  
®
Such keyboards are supplied with many Gateway 2000 computers. If you program  
one of these “spare” keys to produce both hotkey keystrokes, or if you program a  
set of these keys to produce the hotkey and channel-number keystrokes, you’ll be  
able to select channels, lock the Switch, etc., with as few as one or two keypresses.  
H1 Either of the left and right [Ctrl] keys and either of the left and right [Alt]  
keys together (default)  
H2 Either of the left and right [Ctrl] keys and either of the left and right  
[Shift] keys together  
H3 Either of the left and right [Alt] keys and either of the left and right [Shift]  
keys together  
H4 Right [Alt] key only  
H5 Both the left and right [Alt] keys together  
H6 The left [Ctrl] key and the left [Alt] key together  
H7 The right [Ctrl] and the right [Alt] key together  
H8 No hotkey enabled; the hotkey-dependent functions can’t be accessed from  
the keyboard  
25  
 
SERVSWITCH DUO™  
4.2.7 VIEWING THE FIRMWARE REVISION, RESTORING MOUSE FUNCTION, OR RESETTING TO  
FACTORY DEFAULTS  
For technical-support purposes, it might be necessary to find out the firmware-  
release version of the control software in your ServSwitch Duo. Before calling Black  
Box Tech Support about a problem, you can use the [F][1], [F][2], and [F][3]  
commands to retrieve this; each of these commands causes the Switch to briefly  
show one of the digits of the firmware’s version number on its front-panel display.  
For example, if the Switch responds to [F][1][Enter] with the digit “1”, to  
[F][2][Enter] with the digit “0”, and to [F][3][Enter] with the digit “2”, your  
Switch is using firmware version 1.02.  
You can also restore the function of previously disconnected PS/2 type CPU  
mouse ports with the [F][5] and [F][6] commands (see Section 5.11) and you can  
reset all of the Switch’s configuration options to their factory-default states with  
[F][8].  
F1 Display first digit of firmware-version number  
F2 Display second digit of firmware-version number  
F3 Display third digit of firmware-version number  
F4 (Reserved for future use)  
F5 Restore PS/2 mouse function to the currently selected CPU’s mouse port  
F6 Restore IntelliMouse function to the currently selected CPU’s mouse port  
F7 (Reserved for future use)  
F8 Reset all configuration options to their factory-default settings (the Switch  
will briefly show the letter “r” on its front-panel display to indicate that this  
has been completed)  
4.2.8 SETTING THE APPEARANCE OF THE  
ON-SCREEN DISPLAY  
If you want to, you can change the color scheme of the ServSwitch Duo’s on-screen  
display (see Section 5.8) and the time that the confirmation message remains on  
the screen after a channel has been selected. Use the “D” command (type  
[D][digit][Enter]):  
D1 Menu appears with magenta/blue background, green highlight (default)  
D2 Menu appears with red/blue background and green highlight  
D3 Menu appears with blue/black background and light blue highlight  
D4 Confirmation message remains on screen for four seconds (default)  
D5 Confirmation message remains on screen for only two seconds  
D6 Confirmation message remains on screen for six seconds  
26  
 
CHAPTER 4: Configuration  
4.2.9 SETTING THE PASSWORD  
There are many situations where unrestricted access to corporate file servers or  
sensitive information needs to be controlled. In such circumstances, the ServSwitch  
Duo can be locked away in a room or secure cabinet and controlled remotely. In  
this mode, you can type the hotkey sequence followed by the number “0” (zero) at  
the shared keyboard of the active control port in order to “lock” the Switch. When  
you do so—or when the Switch locks itself automatically upon activating screen-  
saver mode; see Section 4.2.2—the Switch blanks the screen, disconnects the  
keyboard and mouse from all of the computers, and displays the letter “P” on its  
front-panel display. Control can only be regained by typing the correct password  
on the keyboard.  
To set this password, get into configuration mode, then type the letter “P” and  
press the [Enter] key. The ServSwitch Duo will light the middle and bottom  
segments of its front-panel display, so that it resembles a wide equals sign, and you  
can then type your password. The password is not case-sensitive and can be any  
combination of keystrokes, including function keys but excluding [Ctrl], [Alt],  
[Shift], and [Enter]. (For example, the password [F4] [F] [R] [E] [D] [Home]  
would be valid.) When you’ve finished typing in your password, press [Enter] to  
save it to the Switch’s EEPROM. (This type of memory does not depend on active  
power or even a battery backup, so it can persist indefinitely.) Don’t worry if you  
type the password incorrectly; you can always re-enter it, even if you’ve exited and  
re-entered configuration mode. (Of course, if somebody locks the Switch or the  
Switch goes into screen-saver mode, and you discover only then that you messed up  
entering the password or can’t remember what the password is, you will have to  
power down the Switch and hold down its SELECT key while powering it back on  
to get back into configure mode—as described in Section 4.2.1—in order to  
change the password.)  
If you want to remove the password after setting one, get into configuration  
mode, type the letter “P”, and press the [Enter] key as before, but then press  
[Enter] without typing in any other characters. (If you try to lock the Switch before  
you’ve set a password, or after you’ve removed the password, the Switch will still  
blank the video, but it won’t prevent someone from selecting another channel;  
see the paragraph about the lock function in Section 5.3.)  
4.2.10 EXITING CONFIGURATION MODE  
When you’ve finished configuring the ServSwitch Duo, simply type the letter “E”  
and press [Enter] to exit the configuration mode and return to normal operation.  
The attached computers can now be switched on.  
27  
 
SERVSWITCH DUO™  
5. Operation  
This chapter explains the general operation of the ServSwitch Duo. We  
recommend that you read this chapter carefully before starting to use the Switch;  
also make sure you have read the important note on page 20.  
5.1 Power Status  
At power-up, the ServSwitch Duo selects CPU channel #1 and displays “1” unless  
a password has been set. If a password has been set, the Switch will display “P” and  
remain locked until a valid password is entered. The 12- and 16-port models will  
also light their Power LED.  
5.2 The Status LEDs  
The green CPU-status LEDs numbered 1 through n (where n is the total number  
of CPU ports—4, 8, 12, or 16—on the Switch) show the ON/OFF status of the  
computers connected to the corresponding CPU ports. This status is derived from  
the computer’s keyboard connection and operates even when the ServSwitch Duo  
is powered off. See also the “PC bootup sequence” paragraph in Section 5.6.  
The red status LEDs (A and B) show the activity status of the local and remote  
keyboard/monitor/mouse control ports. When port A is active, port B is disabled,  
and vice versa. When the Switch is idle, it activates one of these ports and lights the  
associated LED when it detects keyboard or mouse activity on that port. When no  
keyboard or mouse data has been detected on the active port for the duration of  
the switchover-timeout period (see Section 4.2.4), the port becomes inactive, its  
LED goes out, and the other control port can then be used.  
5.3 The Front-Panel Pushbuttons and the Remote-Control Module  
SELECT key and Remote-Control Module  
You can use the SELECT key to select which CPU channel (CPU port) is currently  
controlled by the active control port. Press the key once during normal operation  
to select the next CPU channel in sequence (for example, to select channel 6 if  
channel 5 is currently selected); press the key repeatedly to manually cycle through  
the channels.  
You can also use the SELECT key to access the ServSwitch Duo’s configuration  
mode (see Section 4.2.1). To access configuration mode while the Switch is  
operating, press the SELECT key and hold it down for 5 seconds until “C” appears  
on the Switchs front-panel display.  
28  
 
CHAPTER 5: Operation  
An optional Remote-Control Module (“RCM” for short, our product code  
KV6REM) is also available for the ServSwitch Duo. It’s a small hand-held  
component—with its own copies of the Switch’s SELECT key and front-panel  
display—whose 10-foot (3-m) cord you can plug into the Switch’s RS-232 port.  
This is particularly useful in applications where the ServSwitch Duo is located  
some distance from the shared keyboard, mouse, and monitor. The RCM can  
be conveniently attached to your keyboard with the included Velcro strips so you  
can have channel information and channel-selection control at your fingertips.  
AUTO key  
The AUTO key puts the ServSwitch Duo into autoscan mode. You can choose  
which ports the Switch scans, and how long it pauses at each port during a scan,  
with the “L” and “T” commands in configure mode (see Section 4.2.3). Note that,  
in cascaded systems, you can’t scan all of the CPU ports on all Switches in the same  
scan; you have to press the AUTO key individually on each Switch. For more  
information on autoscanning, see the “Use {Hotkeys} + [A]...” paragraph in  
Section 5.7.  
AUTO and SELECT keys pressed together: The “Lock” function  
Pressing both the AUTO and SELECT keys at the same time will “lock” the  
ServSwitch Duo, causing it to disable all video output and select CPU channel 0  
(zero, the “nothing” channel, something like your local public-television station  
after it goes off the air). If a password has been set for the Switch, the Switch will  
display “P” and wait for the password to be entered before unlocking itself; until  
this is done, the Switch will ignore all other keyboard and mouse data and all  
further presses of the front-panel or RCM buttons. If there is no password currently  
set for the Switch, it will still blank the video and select channel zero (and show “0”  
on its front-panel display), but it will still respond as normal to all input, so it can  
easily be switched to any active CPU channel.  
AUTO and SELECT keys pressed together for 5 seconds: The “Keyboard and  
mouse reset” function  
Pressing both the AUTO and SELECT keys at the same time and holding them in  
for five seconds will blank the ServSwitch Duo’s display and cause the Switch to cut  
off power to the shared keyboards and mice of both control ports in order to  
completely reset them. After several more seconds, the Switch resumes supplying  
power to the keyboards and mice and returns to normal operation. This reset  
function has no effect on the computers connected to the Switch.  
29  
 
SERVSWITCH DUO™  
5.4 The Status Display  
The ServSwitch Duo’s front-panel 7-segment status display usually shows the  
number of the currently selected computer channel, while the dot LED alongside  
it flashes in response to data from the shared keyboard or mouse, as shown in the  
top illustration in Figure 5-1 below. If you select autoscan mode, however, the  
display will alernately (a) display the current channel number and (b) light each of  
its outer six LED segments, one after the other, in a clockwise sequence, as shown  
in the second illustration. If the Switch is in configuration mode, it will display “C”.  
If the Switch has been locked, it will display “P”, as shown in the third illustration,  
until a valid password has been typed to unlock the unit. Lastly, if the screen-saver  
mode has been activated, the channel number will flash.  
DISPLAY SHOWS:  
MEANING:  
Channel number 1 through 16,  
steadily lit  
That channel is selected  
As above, with flashing dot in  
lower right-hand corner  
Switch is receiving keyboard or  
mouse data to be transmitted to  
the selected computer  
Zero  
Display is disabled, but not controls  
Alternately, channel number and  
clockwise progression of lit  
segments  
Switch is in autoscan mode,  
scanning from channel to  
channel at user-selected rate  
The letter “P”  
The letter “C”  
Switch is locked and is waiting  
for the password to be entered  
Switch is in configuration mode  
Channel number, flashing  
Switch is in screen-saver mode  
and is waiting for keyboard or  
mouse activity to restore video  
Figure 5-1. The front-panel status display.  
30  
 
CHAPTER 5: Operation  
5.5 Using the Dual Control Ports (A and B)  
The ServSwitch Duo has two control ports, “A” and “B.” Each control port has a  
keyboard, mouse, and monitor connection, and either can be used to access the  
Switch. Typically port A is used for local access, and port B for remote access from  
up to 65 feet (20 m) away. The Switch sends the video image from the selected  
CPU to the monitors on both ports, but it will accept keyboard and mouse data  
from only one control port at a time. While the other port is active, the Num Lock,  
Caps Lock, and Scroll Lock LEDs on the inactive control port’s keyboard will flash,  
indicating that the port is currently disabled. Once there has been no keyboard or  
mouse data on the active control port for the duration of the “switchover timeout”  
period (see Section 4.2.4), the other keyboard and mouse can be used. Once  
activity is detected on the second control port, that port becomes the active port  
and the first port is disabled. The red status LEDs on the Switch’s front panel (see  
Section 5.2) show which port is currently active; if neither the A or B LED is lit,  
neither control port is active, so either may be used.  
5.6 Things To Keep in Mind About the Keyboards and Mice  
PC bootup sequence: When your PCs are powered on, they communicate with any  
attached keyboards and mice and load the setup parameters required by their  
particular operating systems. It is necessary for the ServSwitch Duo to be attached  
and powered on during this sequence so that it can give the PCs the required  
responses and keep track of all the modes and settings requested by each of the  
connected PCs.  
Mouse characteristics: Do not unplug a PS/2 mouse connection from a PC while  
the PC is on. Because of the way PS/2 mice communicate, the PC will lose mouse  
function and you will have to reboot the PC to regain normal operation.  
Unplugging a shared PS/2 mouse from the ServSwitch Duo will have no  
immediate effect, but the PC will lose mouse function as soon as you plug the  
mouzse back in. (RS-232 mice can usually be freely unplugged and replugged,  
provided that one was connected when the operating system initially booted.) The  
ServSwitch Duo has a PS/2 mouse-recovery system which allows you to disconnect  
and reconnect the shared mouse without powering down the system, but we  
recommend using this only when absolutely necessary. See Section 5.10 for details.  
Keyboard- and mouse-mode handling during channel switching: The ServSwitch  
Duo keeps a log of the keyboard and mouse modes and resolution settings  
requested by each of the connected PCs, including the keyboard Num Lock, Caps  
Lock, and Scroll Lock states. These settings are automatically restored to the  
shared keyboard and mouse when the ServSwitch Duo channel is switched,  
ensuring maximum software compatibility.  
31  
 
SERVSWITCH DUO™  
5.7 Keyboard Control: Hotkey Commands  
You can control many functions on the ServSwitch Duo—such as CPU-channel  
selection, autoscanning, or locking—from the keyboard, using commands  
triggered with the Switch’s currently selected hotkey combination. All of the  
hotkey-control commands are invoked by holding down the one or two hotkeys  
and then pressing a command key. By default, the two hotkeys are [Ctrl] and [Alt],  
although other keystroke combinations can be selected (see Section 4.2.6).  
Normally, when you send a hotkey command, you have to release the hotkeys  
and the command key before you can send another one. The one exception to this  
rule is {Hotkeys} + [Tab], the “switch to next CPU channel” command; you can  
“tab through” the channels by holding down the hotkeys and repeatedly pressing  
[Tab].  
The hotkey commands are summarized below. Note that to generate the  
numeric digits in the commands that contain them, you need to press the number  
keys on the top row of the main section of the keyboard, not the number keys on  
the keypad; the Switch will not recognize keypad numbers.  
• Use {Hotkeys} + [x], where x is a number from one to nine, to switch to the  
corresponding CPU channel. If you try to select a channel with a higher  
number than the Switch has ports, the Switch will ignore the command and  
pass it through to the currently selected computer.  
• Use {Hotkeys} + [1] then [x], where x is a number from one to six, to switch to  
the corresponding CPU channel ([1][1] = channel 11, [1][2] = chanel 12, and  
so on). If you try to select a channel with a higher number than the Switch has  
ports, the Switch will ignore the command and pass it through to the currently  
selected computer. To make sure that the Switch doesn’t switch prematurely to  
channel 1, hold down the hotkeys until you enter the second digit, then release  
them.  
• Use {Hotkeys} + [Tab] to switch to the next channel in numeric sequence.  
• Use {Hotkeys} + [M] to get the Switch to display its on-screen menu for  
selecting computers by name.  
• Use {Hotkeys} + [A] to have the Switch start autoscanning (briefly displaying  
the video from each CPU channel in turn). You can control whether or not it  
scans empty channels, and for how long it pauses at each channel, with the “L”  
and “T” configuration commands respectively (see Section 4.2.3). To stop  
autoscanning, simply select a fixed channel using the on-screen menu, the  
Switch’s SELECT button, the keyboard hotkeys, or the mouse.  
32  
 
CHAPTER 5: Operation  
Please note that, in cascaded systems, it is not possible to scan through all of  
the channels on every Switch in the same scan. Each Switch must be scanned  
separately.  
• Use {Hotkeys} + [0] to select nonexistent “channel zero” in order to shut off  
the video output from the Switch to the shared monitors. The Switch’s front-  
panel display will show “0”. You can re-enable video by selecting another  
channel through the keyboard, SELECT button, on-screen menu, or mouse.  
• Use {Hotkeys} + [L] to lock the Switch (disable its shared keyboard and mouse  
and select nonexistent “channel zero” in order to and shut off the video  
output from the Switch to the shared monitors). If a password has not been set  
(see Section 4.2.9), the Switch behaves exactly as if you had entered  
{Hotkeys} + [0] (see above). If a password has been set, the Switch displays “P”  
to indicate that a valid password must be entered to unlock the switch; simply  
type in the password followed by the [Enter] key to do so. Note that if anyone  
has tried to type something at the shared keyboard while the Switch is locked,  
you will have to press [Enter] to clear those characters so that they won’t  
invalidate the password when you proceed to type it in.  
• Use {Hotkeys} + {Channel Address} to select a CPU channel in a cascaded  
system (see Section 5.12). The {Channel Address} is a series of one- or two-digit  
channel numbers that specify the “path” to follow to get from the master  
Switch to the desired CPU channel on the subsidiary Switch. The numbers in  
the {Channel Address} can be single digits if all of the Switches in the cascade  
are 4- or 8-port units; if any are 12- or 16-port units, you’ll have to add a leading  
zero before the single-digit numbers. For example, if you want to access  
CPU channel 16 on a “second-layer” subsidiary Switch connected to  
CPU port 2 (“02”) on a “first-layer” subsidiary Switch connected to  
CPU port 1 (“01”) on the master Switch, you would enter:  
{Hotkeys} + [0][1][0][2][1][6].  
To make sure that the Switch doesn’t switch prematurely to the wrong  
channel, hold down the hotkeys until you enter the last digit, then release  
them.  
33  
 
SERVSWITCH DUO™  
Examples of common hotkey commands (assuming the hotkeys are [Ctrl] and  
[Alt]):  
To select channel 2:  
Press and hold [Ctrl] and [Alt], press and release [2], release [Ctrl] and [Alt].  
To “tab through” channels:  
Press and hold [Ctrl] and [Alt], press and release [Tab] (repeat as many times  
as necessary), release [Ctrl] and [Alt].  
To select channel 12 on a 12-port or 16-port Switch:  
Press and hold [Ctrl] and [Alt], press and release [1], press and release [2],  
release [Ctrl] and [Alt].  
To select channel 5 on a subsidiary Switch connected to port 13 on a master Switch:  
Press and hold [Ctrl] and [Alt], press and release [1], press and release [3],  
press and release [0], press and release [5], release [Ctrl] and [Alt].  
To select channel 7 on an 8-port subsidiary Switch connected to port 4 on a 4-port master  
Switch:  
Press and hold [Ctrl] and [Alt], press and release [4], press and release [7],  
release [Ctrl] and [Alt].  
34  
 
CHAPTER 5: Operation  
5.8 On-Screen Menu Control  
Another convenient way to select CPU channels on the ServSwitch Duo is through  
the Switch’s on-screen menu. This menu consists of channel numbers (and, in  
cascaded systems, channel addresses) paired with computer names that you assign.  
The menu is called up by pressing the hotkey sequence followed by the letter “M”  
at the shared keyboard. When the menu is first called up, there will be no names  
listed for any of your computers; you have to enter the names and channel  
numbers that will make up the menu. (When you’re finished, press [Esc] to exit.)  
In the menu for 4-port and 8-port models, channel numbers and addresses are  
shown as single digits:  
Computer  
Port  
NT Server A  
355  
356  
1
NT Server B  
Local IBM PC  
Local Compaq PC  
Web Browser  
Comms Server A  
Comms Server B  
Fred’s PC  
2
4
5
6
7
In the menu for 12-port and 16-port models, channel numbers and addresses  
are shown as double digits:  
Computer  
Port  
NT Server A  
030505  
030506  
01  
NT Server B  
Local IBM PC  
Local Compaq PC  
Web Browser  
Comms Server A  
Comms Server B  
Jim’s PC  
02  
04  
05  
06  
12  
In each case, the dot (“  
) shows the currently selected computer.  
35  
 
SERVSWITCH DUO™  
5.8.1 ADDING A COMPUTER TO THE MENU LIST  
With the menu visible on the screen, press the [Insert] key. This will cause a new  
“Computer” entry field to be inserted on the menu. This is highlighted in red with  
a flashing cursor to indicate the text entry position. Type in a name up to  
16 characters long (you can use uppercase, lowercase, special, and space  
characters). When you’re finished, press [Enter].  
The red highlighted area now moves into the “Port” entry field, and you can  
enter the port number for the named computer. Specify port numbers with single  
digits on the 4- and 8-port models and double digits on the 12- and 16-port models  
(adding a leading zero if necessary). If you are using cascaded ServSwitch Duo  
units, you’ll have to specify the whole channel address (see Section 5.13 and the  
“{Hotkeys} + {Channel Address}” paragraph in Section 5.7). To specify CPU port 5  
on a subsidiary Switch that is cascaded off CPU port 3 of the master Switch, you  
would enter the channel address as “35” on 4- and 8-port models or as “0305” on  
12- or 16-port models. (Remember that units should not be cascaded more than  
three layers deep.) Press [Enter] again to complete the entry and store it in the  
Switch’s menu memory. The menu can hold over 300 entries.  
Note that you can add another computer to the menu list at any time, and you  
can continue adding computers without exiting the menu. Just press [Insert] again  
to add an entry after the current line, or press [Shift] and [Insert] to add an entry  
before the current line, then input the new name as already described.  
5.8.2 DELETING A COMPUTER FROM THE MENU LIST  
With the menu visible on the screen, highlight the computer to be deleted and  
press the [Delete] key. Press [Enter] to confirm the deletion or [Esc] to abort it.  
5.8.3 EDITING A COMPUTER ON THE MENU LIST  
With the menu visible on the screen, highlight the computer to be edited and  
press the [Shift] and [Delete] keys together. Type in the new computer name and  
port, then press [Enter] to save your changes or [Esc] to abort them.  
36  
 
CHAPTER 5: Operation  
5.8.4 SELECTING A COMPUTER ON THE MENU LIST  
With the menu visible on the screen, highlight the computer to be selected using  
the up- and down-arrow keys and page-up and page-down keys as required. Now  
press the [Enter] key to switch to the highlighted computer. The ServSwitch Duo  
has an advanced “connection confirmation” facility which is particularly useful in  
systems where many computers are displaying the same or very similar video: The  
selected computer name and port number will briefly flash up on the screen to  
confirm the selection has been made; if it is not possible to make the connection,  
perhaps because a cascaded unit is not switched on or is in use locally, the menu  
will flash “computer unavailable” until you press [Esc] to abort your selection.  
(You can configure how long this “confirmation message” stays on screen; see  
Section 4.2.5.)  
5.8.5 EXITING THE MENU  
When you are finished making your desired changes to the menu, press the [Esc]  
(escape) key to exit back to normal operation.  
5.8.6 CONFIGURING THE MENU  
See Section 4.2.8 for details if you want to change the menu’s color scheme or  
how long the on-screen confirmation message for channel selection is displayed.  
5.8.7 SUMMARY OF KEYS USED BY THE MENU AND THEIR FUNCTIONS  
• {Hotkeys} + [M] calls the menu up on screen, even if no PC video is present,  
unless the Switch is locked.  
• [Insert] adds a computer entry after the currently selected line.  
• [Shift] + [Insert] adds a computer entry before the currently selected line.  
• [Delete] deletes the currently selected computer entry.  
• [Shift] + [Delete] edits the currently selected computer entry.  
• [Enter] confirms an addition, change, or deletion, or selects a computer.  
• [Esc] aborts an addition, change, or deletion, or quits the menu entirely.  
• [] (the up-arrow key) scrolls one line up the menu.  
• [] (the down-arrow key) scrolls one line down the menu.  
• [PgUp] (the page-up key) moves to the top of the menu page, or up 8 lines  
if the currently selected line is more than 8 lines from the top.  
• [PgDn] (the page-down key) moves to the bottom of the menu page, or down  
8 lines if the currently selected line is more than 8 lines from the bottom.  
37  
 
SERVSWITCH DUO™  
5.9 Mouse Control  
Yet another convenient way to select CPU channels on the ServSwitch Duo is  
through a three-button mouse, if this feature is enabled (see Section 4.2.5). To  
switch to the next channel, simply hold down the central mouse button or “wheel”  
button, then click on the left-hand mouse button.  
5.10 Re-Enabling a Disconnected PS/2 Mouse  
If you disconnect the shared PS/2 mouse from the ServSwitch Duo by accident  
during operation, the mouse will not work right when you plug it back in. To avoid  
having to reboot the entire system in this situation, the Switch has an automatic  
mouse-recovery system.  
With the PS/2 mouse disconnected, change the channel using the SELECT  
button or keyboard hotkeys. The ServSwitch Duo detects that the mouse has been  
disconnected and triggers the automatic recovery system. Plug in the PS/2 mouse  
and the ServSwitch Duo will re-initialize it.  
Alternatively, you can reset the keyboards and mice by holding the SELECT and  
AUTO keys down together for five seconds. When you do, the Switch will perform  
a complete power-off reset of the connected keyboards and mice. This function  
only resets the shared keyboard and mice that are plugged into contol ports A and  
B; it does not affect the status of any of the other ports on the Switch or of the CPU  
connections.  
5.11 Hot-Plugging Devices into the ServSwitch Duo and Re-Enabling  
Disconneccted CPU PS/2 Mouse Ports  
It is advisable to switch off the computer systems that are going to be connected to  
the ServSwitch Duo before installation. However, even if this is not possible, most  
systems can be “hot-plugged” (connected to the Switch while they are powered and  
operating); the PS/2 mouse-port malfunctions this usually causes can often be  
overcome by using the ServSwitch Duo’s mouse-restoration functions. (The  
keyboard connection will normally restore itself automatically.)  
Let’s take this from the top: On many PCs, mouse movement will be lost if the  
PS/2 mouse is unplugged and plugged back in while the PC is running. Mouse  
movement can then only be restored by rebooting the PC. This is because the  
mouse drivers only set up and enable the mouse when the PC is initially booted.  
38  
 
CHAPTER 5: Operation  
If you have powered down your ServSwitch Duo, or if you are attempting to hot-  
plug a system into it, you may be able to restore lost mouse movement using the  
ServSwitch Duo's mouse-restoration functions.  
Mouse-restoration functions should be used with caution, because unpredictable  
results may occur if the wrong mouse type is selected. If in doubt, restore the  
mouse by rebooting the PC normally.  
Standard PS/2 mouse data uses a different data format than IntelliMouse data,  
so two reset functions are provided on the ServSwitch Duo. The type of data format  
expected by the PC depends upon the driver and the type of mouse that was  
connected when the driver was booted. The following table may be used as a guide;  
note that the mouse-reset functions predict the likely mouse resolution settings but  
may not restore the speed or sensitivity of the mouse exactly as they were when the  
PC originally booted:  
Type of mouse/  
system connected  
at bootup:  
Driver type:  
Probable  
expected  
data format:  
Suggested  
restoration  
command:  
PS/2  
PS/2 only  
PS/2  
F5  
F5  
F5  
F6  
PS/2  
IntelliMouse  
PS/2 only  
PS/2  
IntelliMouse  
IntelliMouse  
PS/2  
IntelliMouse  
IntelliMouse  
To restore lost mouse movement on a CPU connected to the ServSwitch Duo:  
1. Select the CPU that has lost its mouse movement.  
2. Press and hold the SELECT button on the front of the ServSwitch Duo for  
five seconds until “C” appears in the front-panel display. The Switch is now in  
configuration mode.  
3. To restore a PS/2 mouse connection, type the letter “F” followed by the  
number “5” followed by [Enter]. Or, to restore an IntelliMouse connection,  
type the letter “F” followed by the number “6” followed by [Enter].  
4. Exit from configure mode by typing the letter “E” followed by [Enter].  
5. Test the mouse movement by moving the mouse a short distance.  
39  
 
SERVSWITCH DUO™  
5.12 RS-232 Control  
There is yet one more way to select channels on the ServSwitch Duo: through its  
RS-232 serial port. (This is a proprietarily pinned DB15 connector; see Section A.3  
of the Appendix for more information.) The normal use of this connector is as the  
attachment point for the Switch’s optional Remote-Control Module, but by using  
an adapter you can connect a different RS-232 device to it. To select a channel  
through this port, the data rate and format of the sending device must be set to  
1200 bps, 8 data bits, no parity, and 1 stop bit. No handshaking (flow control) is  
used by the ServSwitch Duo.  
Simply send the ASCII character for the channel which needs to be selected:  
ASCII “1” (31 hex, 49 decimal) will select channel 1, ASCII “2” (32 hex,  
50 decimal) will select channel 2, and so on. You can select ports 10, 11, 12, 13, 14,  
15, and 16 by sending the ASCII characters “A,” “B,” “C,” “D,” “E,” “F,” and “G”  
respectively.  
5.13 Cascading ServSwitch Duos  
Multiple ServSwitch Duos can be cascaded (connected together in a one-to-many  
scheme) in order to increase the maximum number of available CPU ports in your  
KVM-switching system. This can be particularly useful where clusters of computers  
are located some distance from each other, because each Switch unit acts as a kind  
of signal booster or repeater and can be as much as 100 feet (30 m) away from the  
other Switches in the system. To select channels in cascaded systems, you will need  
to either send hotkey commands from the master Switch’s keyboard (see the  
“{Hotkeys} + {Channel Address}” paragraph in Section 5.7) or select your desired  
channel from the Switch’s on-screen menu (see Section 5.8). Most people find  
using the menu more convenient, because scrolling through and selecting  
computer names from the menu is usually much easier than trying to remember  
and type in channel addresses.  
Though it’s theoreticallly possible to cascade ServSwitch Duos to four, five, or  
more “layers,” we recommend that you limit your setup to three, because the  
channel addresses for CPU ports on Switches beyond the third layer are too long to  
be entered in the menu.  
40  
 
CHAPTER 5: Operation  
For an example of hotkey switching, consider a situation in which two ServSwitch  
Duo units, unit “A” and unit “B,” are connected together as shown in Figure 5-1 on  
page 42. To select the computer attached to port 3 on ServSwitch Duo “B,” you  
would press and hold down the hotkeys, then press and release “2,” press and  
release “3,” and finally release the hotkeys. This causes the master Switch, unit “A,”  
to switch to its port 2, to which the subsidiary Switch is attached, and send the  
subsidiary Switch the command to switch to port 3, to which your desired  
computer is attached. (If there were any 12- or 16-port Switches in the system, you  
would have to use two digits to designate each port, inserting a leading zero when  
necessary.)  
Two more examples, assuming that the hotkeys are the default combination of  
[Ctrl] + [Alt]:  
To switch to channel 5 of an 8-port Switch attached to channel 1 of your 4-port master  
Switch:  
Press and hold [Ctrl] + [Alt], press and release [1], press and release [5],  
release [Ctrl] + [Alt].  
To switch to channel 7 of a 12-port Switch attached to channel 14 of your 16-port master  
Switch:  
Press and hold [Ctrl] + [Alt], press and release [1], press and release [4], press  
and release [0], press and release [7], release [Ctrl] + [Alt].  
Please note that it is not possible to autoscan every channel in a cascaded system  
with a single scan. Cascaded Switches must be scanned individually using their  
front-panel pushbuttons or {Their Hotkeys} + [A].  
41  
 
SERVSWITCH DUO™  
2
3
4
1
CPUs  
ServSwitch Duo B  
(second layer)  
3
2
4
1
CPUs  
ServSwitch Duo A  
(first layer)  
Shared  
Keyboard,  
Mouse, and  
Monitor  
Figure 5-1. A typical cascade of two ServSwitch Duos.  
42  
 
CHAPTER 6: Troubleshooting  
6. Troubleshooting  
6.1 Things To Try  
This section suggests possible answers for a number of problems that people  
sometimes encounter when trying to operate the ServSwitch Duo. If the suggested  
actions don’t solve your problem, or if you don’t see a listing for the type of trouble  
you’re having, contact Black Box Technical Support as described in Section 6.2.  
Problem:  
Poor video quality with smearing, fuzziness, or rippling.  
Possible Solution:  
Use shielded or screened coaxial video cables to connect your devices to the  
ServSwitch Duo.  
Problem:  
Your mouse does not move the cursor/pointer.  
Possible Solutions:  
If you move the mouse and the activity indicator (the dot on the 7-segment  
display) does not flash, then the ServSwitch Duo is not receiving data from the  
mouse. Check the mouse connection to the Switch; if it’s OK, try resetting the  
mouse using the reset function (see Section 3.3) or powering the Switch OFF and  
then ON again. If you are attempting to connect the Switch to a CPU with a PS/2  
mouse connection that has not been powered down, you will need to use the  
mouse-restoration function F5 or F6 (see Section 5.11).  
Make sure that your software is configured to accept a Microsoft compatible  
mouse of the type that you have connected (PS/2 or RS-232).  
Make sure that (a) the mouse and computer were both connected to the  
ServSwitch Duo before any part of the system was powered up, and (b) the Switch  
was powered ON before the attached computer. If you’re not sure whether this was  
the case, then (if it’s possible to do so) power everything down, make sure all cable  
connections are correct and secure, power up the Switch, then power up all  
attached computers.  
43  
 
SERVSWITCH DUO™  
Problem:  
Your keyboard does not function or functions only intermittently. The Num Lock  
LED does not always light when the Num Lock key is pressed.  
Possible Solution:  
Some older keyboards were designed for use with specific computers and are not  
truly PC/AT or PS/2 compatible. These are not common, but if you’re having  
problems like this and you’re using an old keyboard, try a newer keyboard.  
Problem:  
Just using your mouse normally causes the CPU channel to change unexpectedly.  
Possible Solutions:  
Some cheaper mice are not fully compatible with the ServSwitch Duo and can lose  
data, which—if mouse switching is enabled (see Section 4.2.5)—sometimes causes  
the Switch to interpret a data stream as a channel-change request. Try using a  
®
®
Microsoft, Logitech, IBM, Compaq , or Hewlett-Packard mouse instead.  
Make sure that you are using a Microsoft compatible mouse driver on your PC.  
Some drivers by other manufacturers can cause the mouse to use proprietary  
mouse-data formats that the Switch doesn’t support. If you have unplugged and  
reconnected a mouse to the ServSwitch Duo, make sure that you reset it (see  
Section 5.10) or—especially if the mouse is an IntelliMouse—use the mouse-  
restoration function (see Section 5.11).  
Problem:  
The cursor/pointer jumps around the screen after you disconnect the mouse cable  
or power down the ServSwitch Duo.  
Possible Solution:  
If you have disconnected and reconnected a CPU mouse cable or you have  
powered down the ServSwitch Duo, and you’re using a PS/2 mouse or  
IntelliMouse, the mouse might have gotten out of sync with the PC. Try the mouse-  
reset function (see Section 5.10), the mouse-restoration function (see  
Section 5.11) or reboot the CPU.  
44  
 
CHAPTER 6: Troubleshooting  
Problem:  
The ServSwitch Duo does not power on correctly (display is blank or stuck after  
power-up).  
Possible Solution:  
Power down all CPUs attached to the ServSwitch Duo. Then power down the  
Switch itself—preferably, if it’s plugged into a switchable power outlet, by switching  
off the power to the outlet—and leave it OFF for 10 seconds. Then power the  
Switch back up. If this doesn’t solve the problem, the ServSwitch Duo is probably  
defective; call Black Box Technical Support as directed in Section 6.2.  
Problem:  
Video appears to be lost after a PC has gone into auto-power-down mode. Moving  
the mouse and typing at the keyboard does not wake it up.  
Possible Solutions:  
This is an example of a simple problem that becomes magnified into bigger  
problems: Some computers output an incomplete video signal in auto-power-down  
mode. The ServSwitch Duo can’t “lock on” to such signals and, as a result, can’t  
display its on-screen menu. But the Switch’s menu circuitry captures the keyboard  
and mouse data anyway, so the computer never gets it and never “wakes up.” Thus  
the system appears to “hang.”  
To restore the video under these conditions, press [Escape] or [Enter] or  
change the CPU channel by typing in your hotkey sequence followed by the  
channel number. If you have any PCs in your ServSwitch Duo system that tend to  
do this, you should be careful not to leave your user station idle with the menu on  
screen.  
Problem:  
Compaq MX11800 model integrated keyboard and mouse only: The mouse consistently  
fails to boot when the Switch is connected to PCs running Windows NT 4.0  
through their PS/2 style mouse ports.  
Possible Solutions:  
There are three possible solutions to this problem:  
1. Use a different type of mouse.  
2. Connect the Switch to your NT 4.0 PCs through adapters and their serial ports  
rather than through their PS/2 ports.  
3. Select channel 0, or another channel that is not connected to an NT 4.0 PC,  
while NT is booting. You should be able to use the system normally once the logon  
screen appears.  
45  
 
SERVSWITCH DUO™  
6.2 Calling Black Box  
If you determine that your ServSwitch Duo is malfunctioning, do not attempt to alter  
or repair the unit. It contains no user-serviceable parts. Contact Black Box Technical  
Support at 724-746-5500.  
Before you do, make a record of the history of the problem. We will be able to  
provide more efficient and accurate assistance if you have a complete description,  
including:  
• the nature and duration of the problem.  
• when the problem occurs.  
• the components involved in the problem—that is, what types of computers,  
what type of keyboard, brand of mouse, make and model of monitor, etc.  
• any particular application that, when used, appears to create the problem  
or make it worse.  
• the results of any testing you’ve already done.  
6.3 Shipping and Packaging  
If you need to transport or ship your ServSwitch Duo:  
• Package it carefully. We recommend that you use the original container.  
• Before you ship the unit back to Black Box for repair or return, contact us  
to get a Return Authorization (RA) number.  
46  
 
APPENDIX: Cable and Connector Guidelines  
Appendix:  
Cable and Connector Guidelines  
IMPORTANT NOTE  
The maximum cable lengths supported vary widely between devices and  
cables. It might be possible to use cables that are longer than those  
specified below with certain PCs and peripherals, but this cannot be  
guaranteed. If you experience problems, try using shorter cables.  
A.1 Cabling: Keyboard, Monitor, and Mouse to ServSwitch Duo  
All of the shared devices plug directly into the relevant ports at the rear of the  
ServSwitch Duo. If you use a PC/AT style keyboard you will need a PC/AT (5-pin  
DIN female) to PS/2 (6-pin mini-DIN male) adapter. (These are readily available  
from Black Box.) User Extension Cables can be used to increase the distance from  
ServSwitch Duo up to 30 ft. (9.1 m; see Section 3.3); many keyboards and mice will  
operate at distances up to 65 ft. (20 m), but do not count on this.  
A.2 Cabling: ServSwitch Duo to PCs  
Video: HD15 male to HD15 male, wired as a standard VGA PC-to-monitor cable.  
There are two types commonly available. The better type, which will carry video  
very well, are constructed with coaxial cable cores. The not-so-good type—cheaper  
cable more suited for data communication—is often used, but can degrade video  
quality, especially over longer distances. Avoid using “data cables” longer than  
6 ft./2 meters unless video quality is not important in your application. Good  
coaxial video cables may be run at distances up to 165 ft. (50 m) with little loss of  
video quality, but the longest we recommend going—unless you use the ServSwitch  
Duo Extender (KV6EXT; see its manual for details)—is 100 ft. (30.5 m) over the  
video strand of our CPU Extension Cables (see Section 3.3).  
Keyboard and PS/2 mice: 6 pin mini-DIN male to 6 pin mini-DIN male with all  
lines connected straight through (1 to 1, 2 to 2, etc.). If the PC has a 5-pin DIN  
PC/AT style keyboard connector, you will need a PS/2 to PC/AT keyboard  
adapter, 6-pin mini-DIN female to 5-pin DIN male. (One of these is included for  
each four CPU ports on your Switch; if you need more, they are readily available  
from Black Box.) Keyboard and mouse cables, such as the keyboard and mouse  
strands of our CPU Extension Cables (see Section 3.3), should be no longer than  
100 ft. (30.5 m).  
47  
 
SERVSWITCH DUO™  
RS-232 serial mice: These require a special adapter, with the pinning shown in the  
illustration below, to connect the ServSwitch Duo’s PS/2 mouse port to the RS-232  
port on a PC. One of these adapters is included with your Switch for each four  
CPU ports it has. PS/2 type mouse cables, such as the mouse strand of our CPU  
Extension Cables (see Section 3.3), should be no longer than 100 ft. (30.5 m). If  
you are using a converter at the Switch end instead of the PC end and are running  
regular RS-232 cable, this should not be longer than 50 ft. (15.2 m).  
6-pin mini-DIN attaches to  
Switch or cable from Switch  
DB9 attaches to PC’s serial port or  
cable to PC’s serial port  
KDAT  
RLSD (DCD)  
N/C  
1
1
TD  
RD  
2
2
TD (-12V)  
SGND  
3
3
DTR  
+5V  
4
4
KCLK  
SGND  
5
5
DSR  
-12V  
6
6
RTS  
7
CTS  
N/C  
N/C  
8
RI  
9
Male  
1
5
Male  
5
6
4
3
3
1
2
6
9
9
Female  
5
1
Female  
6
5
4
2
1
6
48  
 
APPENDIX: Cable and Connector Guidelines  
A.3 The Expansion Port  
The DB15 connector on the back of the ServSwitch Duo is a proprietarily pinned  
port using RS-232-type signaling. Its main purpose is to be the attachment point for  
the Switch’s optional Remote Control Module (RCM), but you can also connect an  
RS-232 device to it to perform channel switching. See Section 5.12 for more details.  
The pinout of this connector is pretty simple: Pin 9 (Signal Ground, SGND)  
and Pin 11 (Receive Data, RD) are the only pins used for serial communication  
to other RS-232 devices. All other pins are intended for RCM communication only  
and should be left unconnected; attaching them to any other RS-232 equipment  
could have unpredictable and possibly damaging effects.  
49  
 
SERVSWITCH DUO™  
DISCLAIMERS  
While every precaution has been taken in the preparation of this manual, the  
manufacturer assumes no responsibility for errors or omissions. Neither does the  
manufacturer assume any liability for damages resulting from the use of the  
information contained herein. The manufacturer reserves the right to change the  
specifications, functions, or circuitry of the product without notice.  
The manufacturer cannot accept liability for damage due to misuse of the  
product or due to other circumstances outside the manufacturer’s control. And  
the manufacturer will not be responsible for any loss, damage, or injury arising  
directly or indirectly from the use of this product.  
50  
 
NOTES  
 

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