Black Box Switch SW925A User Manual

APRIL 2000  
SW925A  
SW925AE  
SW926C  
SW927C  
SW928C  
SW929C  
Modular Smart Switch  
Modular Smart Switch  
ER  
POW  
BUFFER  
3/4  
F
1/2  
1/4  
12  
11  
10  
9
8
7
6
5
4
3
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© Copyright 2000. Black Box Corporation. All rights reserved.  
CUSTOMER  
SUPPORT  
INFORMATION  
Order toll-free in the U.S.: Call 877-877-BBOX (outside U.S. call 724-746-5500)  
FREE technical support 24 hours a day, 7 days a week: Call 724-746-5500 or fax 724-746-0746  
Mailing address: Black Box Corporation, 1000 Park Drive, Lawrence, PA 15055-1018  
1000 Park Drive  
Lawrence, PA 15055-1018  
724-746-5500  
Fax 724-746-0746  
 
MODULAR SMART SWITCH  
NORMAS OFICIALES MEXICANAS (NOM)  
MODULAR SMART SWITCH  
12. Precaución debe ser tomada de tal manera que la tierra fisica y la polarización  
del equipo no sea eliminada.  
ELECTRICAL SAFETY STATEMENT  
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.  
INSTRUCCIONES DE SEGURIDAD  
14. El equipo eléctrico debe ser limpiado únicamente de acuerdo a las  
recomendaciones del fabricante.  
1. Todas las instrucciones de seguridad y operación deberán ser leídas antes de  
que el aparato eléctrico sea operado.  
15. En caso de existir, una antena externa deberá ser localizada lejos de las lineas  
de energia.  
2. Las instrucciones de seguridad y operación deberán ser guardadas para  
referencia futura.  
16. El cable de corriente deberá ser desconectado del cuando el equipo no sea  
usado por un largo periodo de tiempo.  
3. Todas las advertencias en el aparato eléctrico y en sus instrucciones de  
operación deben ser respetadas.  
17. Cuidado debe ser tomado de tal manera que objectos liquidos no sean  
derramados sobre la cubierta u orificios de ventilación.  
4. Todas las instrucciones de operación y uso deben ser seguidas.  
18. Servicio por personal calificado deberá ser provisto cuando:  
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..  
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  
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.  
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.  
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.  
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MODULAR SMART SWITCH  
MODULAR SMART SWITCH  
TRADEMARKS USED IN THIS MANUAL  
Contents  
Any trademarks mentioned in this manual are acknowledged to be the property of the  
trademark owners.  
Chapter  
Page  
1. Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8  
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9  
2.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9  
2.2 Product Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9  
3. Installing Port Modules and Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11  
3.1 Fitting Expansion-Buffer Memory . . . . . . . . . . . . . . . . . . . . . . . . . . .11  
3.2 Fitting Port Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12  
4. Configuring the Modular Smart Switch . . . . . . . . . . . . . . . . . . . . . . . . . . .14  
4.1 Setting the Global Timeout Period . . . . . . . . . . . . . . . . . . . . . . . . . . .15  
4.2 Setting Parallel Ports as Inputs or Outputs . . . . . . . . . . . . . . . . . . . .17  
4.3 Setting Serial Port Protocols and Options . . . . . . . . . . . . . . . . . . . . .18  
5. Installing the Modular Smart Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21  
5.1 Selecting Ports for Your Equipment . . . . . . . . . . . . . . . . . . . . . . . . . .21  
5.2 Positioning the Modular Smart Switch . . . . . . . . . . . . . . . . . . . . . . . .21  
5.3 Cable Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21  
5.4 Connecting Devices to the Modular Smart Switch . . . . . . . . . . . . . .21  
5.5 Switching On . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22  
5.6 Enabling Computers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22  
5.7 Using the Modular Smart Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . .24  
5.8 Port Indicators (1 to 12) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24  
5.9 Buffer Status Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25  
6. Using the Control Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26  
6.1 Installing the Resident Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26  
6.2 Running the Software from the DOS Prompt . . . . . . . . . . . . . . . . . .26  
6.3 Command-Line Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27  
®
6.4 Running the Software from within Microsoft Windows . . . . . . . . . .28  
6.5 Using the Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29  
6.6 Main Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30  
6.7 Selecting a Destination Printer, Plotter, or Modem . . . . . . . . . . . . .31  
6.8 Direct Output of Typed Keyboard Characters . . . . . . . . . . . . . . . . . .33  
6.9 Using the Functions Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34  
6.9.1 Sending a Form Feed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34  
6.9.2 Clearing Unwanted Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34  
6.9.3 Ending Long or Infinite Timeouts . . . . . . . . . . . . . . . . . . . . . .34  
6.10 Setting the Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35  
6.10.1 Multiple Copies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35  
6.10.2 Changing the Timeout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36  
6.10.3 Selecting a PC Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36  
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MODULAR SMART SWITCH  
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Chapter  
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Chapter  
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7. Serial Port Control Utility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37  
Appendix A: Serial Ports ..................................................................................53  
A.1 RS-232 and RS-422 Pin Assignments....................................................53  
A.2 Connecting to Computers—RS-232 Connections ..............................54  
A.2.1 RS-232 Connections to IBM PCs and Compatibles ..................54  
A.2.2 RS-232 Connectors to IBM AT and compatibles ......................55  
A.3 Connecting to Printers .........................................................................56  
A.4 Connecting to Modems........................................................................57  
A.5 Connecting to Plotters..........................................................................58  
A.6 Connecting to NEC Spinwriter............................................................59  
A.7 Connecting to DEC LN03 Laser Printer .............................................60  
A.8 RS-422 Cables........................................................................................61  
8. Using the Modular Smart Switch to Transfer Files . . . . . . . . . . . . . . . . . .40  
8.1 Transferring Files between IBM compatible PCs . . . . . . . . . . . . . . . .40  
8.2 Using the Software with File-Transfer Software . . . . . . . . . . . . . . . . .42  
8.3 Transferring Files Between PCs Not Compatible  
with IBM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42  
8.4 General Hints and Tips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43  
9. Software Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44  
9.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44  
9.2 Connect Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45  
9.2.1 Selecting a Destination Port . . . . . . . . . . . . . . . . . . . . . . . . . . .45  
9.2.2 Printing Several Copies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45  
9.2.3 Broadcasting Data to Several Devices . . . . . . . . . . . . . . . . . . . .45  
9.2.4 Varying the Timeout Period . . . . . . . . . . . . . . . . . . . . . . . . . . .46  
9.2.5 Disabling Software Commands . . . . . . . . . . . . . . . . . . . . . . . . .46  
9.2.6 Removing Line Feeds at End of Software  
Appendix B: Parallel Ports ...............................................................................62  
B.1 Parallel Pin Assignments ......................................................................62  
B.2 Cable for IBM PC/XT, AT, or compatible..........................................64  
B.3 Cable to a 36-pin Amphenol ................................................................64  
Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47  
9.3 Clear Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47  
9.4 End of File Command . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47  
9.5 Creating Batch Files to Send Commands (IBM  
compatible PCs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .47  
9.6 Setting Default Start of Day Destination Ports . . . . . . . . . . . . . . . . . .49  
10. Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50  
10.1 Self-Test at Power-On . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50  
10.2 Parallel Interfaces—No Data Transmitted through the  
Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50  
10.3 Parallel Interfaces—Corrupted, Extra, or Lost Data . . . . . . . . . . . .51  
10.4 Problems Interfacing Serial Devices . . . . . . . . . . . . . . . . . . . . . . . . .51  
10.5 Serial Interfaces—No Data Transmitted through the  
Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51  
10.6 Serial Interfaces—Corrupted Data . . . . . . . . . . . . . . . . . . . . . . . . . .51  
10.7 Merged Printouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52  
10.8 Print Data Transmitted but File Transfer Fails . . . . . . . . . . . . . . . .52  
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MODULAR SMART SWITCH  
MODULAR SMART SWITCH  
1. Specifications  
2. Introduction  
Base Chassis (SW925A/SW925AE)—6 dual-port module slots, 2 memory  
The Modular Smart Switch is suitable for a wide variety of applications,  
including printer and plotter sharing, file transfer, modem sharing, network  
switching, electronic point-of-sale systems, access control networks, machine  
tool control, data collection, and mainframe connections.  
module slots, integral power supply  
PortsParallel: Dual parallel-port module slots with DB25 female connectors.  
Automatic in/out detection or selectable by option switches. 30,000 cps.  
Serial: Dual serial-port modules contain 2 bidirectional RS-232/422  
interfaces with DB25 male connectors.  
2.1 Features  
• Modular and user-upgradeable construction.  
Switches—Control protocol and RS-232/422 selection and baud rates.  
Baud Rates—300, 1200, 2400, 4800, 9600, 19200, 38400, and 57600 bps  
Handshake—CTS/DTR hardware XON/XOFF, ETX/ATK.  
• Mixed serial (RS-232/422) and parallel ports in any combination.  
• Up to 12 ports and 4 MB of buffer memory.  
• Automatic printer and plotter sharing.  
Functional Features—Code-string control; data broadcast to multiple ports;  
print to first available printer; file transfer compatible with Laplink,  
Fastlynx, Kermit, Xmodem, etc.  
• Any port can be routed to any other port.  
• File transfer between computers using standard file-transfer software.  
• Memory-resident control software for selecting destination ports.  
• Multiple copies of printouts.  
Timeout—Selectable from 1 to 255 seconds  
Indicators—LEDs: Buffer status, individual channel activity, power  
Power—115 or 230 VAC, 60/50 Hz  
• Unwanted print data can be cleared from the switch’s buffer.  
• Software for high-speed serial data output from PCs.  
• Full-duplex serial data communications.  
Size—3.5"H x 13.1"W x 9.4"D (9 x 33.5 x 24 cm)  
Weight—7.7 lb. (3.5 kg)  
2.2 Product Information  
The following items are available:  
• Modular Smart Switch Chassis w/ 1 Meg Memory (SW925A, SW925AE)  
includes:  
Main chassis with 6 dual-port module slots and 2 memory slots  
Software disk in 3.5" format  
Power lead with 115 VAC or 230 VAC plug  
5 module blanking plates with fixing screws  
This user manual  
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MODULAR SMART SWITCH  
MODULAR SMART SWITCH  
• Dual Serial RS232/422 Port Module (SW926C)  
• Dual Parallel Port Module In/Out (SW927C)  
• 1 Meg Memory Expansion (SW928C)  
3. Installing Memory and Port Modules  
To fit memory and port modules, you will need to remove the lid of your  
Modular Smart Switch. To do this, remove the four retaining screws holding  
the lid in place (see Figure 3-2) and lift the lid away.  
• 2 Meg Memory Expansion (SW929C)  
3.1 Fitting Expansion-Buffer Memory  
The Modular Smart Switch contains two memory module slots (A and B),  
each of which can be fitted with a 1 MB or 2MB buffer memory module (see  
Figure 3-1). The Modular Smart Switch is supplied as standard with a 1 Meg  
buffer memory module fitted in slot A.  
Memory slot B  
Memory slot A  
(fill this first)  
Figure 3-1. Fitting Expansion Buffer Memory Modules.  
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MODULAR SMART SWITCH  
MODULAR SMART SWITCH  
To install additional buffer memory:  
• Make sure that the Modular Smart Switch is powered off.  
• Insert the expansion buffer memory module into slot A or B (slot A  
should be filled first). A polarizing pin ensures that the board is seated  
correctly.  
The installed buffer memory is automatically tested whenever the Modular  
Smart Switch is powered on. The buffer memory indicators will flash while  
the test is in progress and go off when the test is complete. If all the channel  
and buffer indicators come on permanently, then the buffer has been  
installed incorrectly or there is a memory fault.  
CAUTION  
Always observe static handling precautions when installing memory  
modules.  
Position of lid  
retaining screws  
1. Keep the modules in their anti-static bags until you are ready to install  
them.  
2. Never place memory modules in plastic bags or on plastic surfaces.  
Figure 3-2. Fitting Port Modules.  
3. Discharge static from your clothes before handling the modules (you  
can do this by touching an earth-grounded metal device).  
To fit port modules:  
1. Make sure that the Modular Smart Switch is powered off.  
2. Remove the rear- panel blanking plates as appropriate.  
3. Insert the modules as shown in Figure 3-2.  
3.2 Fitting Port Modules  
• Any type of port module can be fitted into any of the six module slots in  
any order.  
4. Push the modules onto the mating connectors on the base board.  
Do not place too much pressure on the board.  
• All slots have equal priority.  
• All print data is routed by default to port 1 unless a destination port has  
been selected. For automatic printer and plotter sharing, the printer or  
plotter should be connected to port 1.  
5. Fix the modules to the rear panel using the screws provided.  
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MODULAR SMART SWITCH  
MODULAR SMART SWITCH  
4.1 Setting the Global Timeout Period  
4. Configuring the Modular Smart Switch  
The ports on the Modular Smart Switch are configured using a number  
of option switches situated on the modules. In addition to the port  
configuration, the global timeout values can be set using option switches  
on the main board. Figures 4-1, 4-2, and 4-3 show the meaning of each  
of the sets of option switches. Set the option switches as required.  
NOTE  
The option switches are only read when the Modular Smart Switch is first  
powered on. Changing the settings while the Modular Smart Switch is  
powered on will have no immediate effect.  
0 0 Timeout = 16 seconds  
0 1  
1 0  
1 1  
Timeout = 30 seconds  
Timeout = 1 minute  
Timeout = 4 minutes  
OFF  
(0)  
ON  
(1)  
1
2
3
4
5
6
Reserved - set to 0  
TEST switch - set to 0 (OFF)  
for normal operation  
Figure 4-1. Setting the Global Timeout Period.  
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Timeout Period  
4.2 Setting Parallel Ports as Inputs or Outputs  
When a user has sent no data for the timeout period, the Modular Smart  
Switch is able to switch to another user. The default timeout setting of 16  
seconds is suitable for most applications. If printouts are ever merged,  
increase the timeout period. Switches 1 and 2 on the base board control the  
global default timeout period used by all the ports. Individual port timeouts  
can be set using the software (see Chapter 6) or by sending software  
commands (see Chapter 9).  
LOW port  
HIGH port  
HIGH port  
switches  
LOW port  
switches  
Dual parallel  
port module  
OFF  
(0)  
ON  
(1)  
1 2 3 4  
ON  
HIGH port switches  
LOW port switches  
Set port as INPUT 1 0  
Set port as OUTPUT 0 1  
1
0
Set port as INPUT  
Set port as OUTPUT  
0
1
Automatic input/output  
detection (* not guaranteed)  
Automatic input/output  
detection (* not guaranteed)  
1 1  
1 1  
Figure 4-2. Selecting the Direction of Parallel Ports (Input or Output).  
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NOTE  
NOTE  
Automatic detection of the direction of parallel ports is achieved by  
detecting the state of the SELECT IN signal on the hardware interface.  
This will operate with most PCs and printers. Automatic detection is not  
guaranteed to work with all equipment, so if you experience any  
problems, set the ports as dedicated inputs or outputs.  
The XON/XOFF setting for printer and plotter con-nections is a  
bidirectional protocol that recognizes the XON and XOFF characters in  
both directions. The XON/XOFF setting for com-puter connections  
recog-nizes the XON and XOFF characters in one direction only. This  
allows graphics, font and other non text data to be sent from computers  
without problems (the XON and XOFF characters often form part of this  
data).  
4.3 Setting Serial-Port Protocols and Options  
Protocols  
Ports on the Modular Smart Switch that are set to XON/XOFF handshake  
will also give the hardware handshake signal to ensure maximum  
compatibility.  
For serial devices, you must set a number of parameters to make sure that the  
Modular Smart Switch is “speaking the same language” as the equipment that  
it will communicate with. These parameters include the handshake mode,  
the baud rate, the parity, the number of bits per character, and the number of  
stop bits. Most computers and printers are able to set these parameters, so it  
is generally advisable to set the fastest available. This is often 9600 baud, 8  
bits per character, one stop bit, no parity, and either hardware handshake or  
XON/XOFF.  
The bidirectional XON/XOFF protocol used for printer and plotter connec-  
tions can also be used for computer connections if the computer will  
never send the XON or XOFF characters as part of the data stream.)  
RS-232/RS-422 Selection  
Each dual serial module supports both RS-232 and RS-422 serial  
communication. The hardware signals for RS-232 and RS-422  
communication appear on different pins of the interface  
(see Appendix A for pin-configuration details).  
Hardware Handshake  
• DTR/CTS (hardware) handshake uses hardware signal lines to control the  
flow of data (pins 5 and 20).  
Software Handshake  
• ETX/ACK—the flow of data is controlled by sending blocks of data and  
waiting for an ACKnowledgement character to be received.  
• XON/XOFF (printer and plotter connections)—the flow of data is  
controlled by the receiving device by transmitting XOFF (stop data flow)  
and XON (start data flow) characters. Set this protocol on ports  
connected to printers and plotters.  
• XON/XOFF (computer connections)—the flow of data is controlled by  
the Modular Smart Switch. This is done by sending XON (start data flow)  
and XOFF (stop data flow) characters to the computer. Set this protocol  
on ports connected to computers.  
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MODULAR SMART SWITCH  
LOW port  
HIGH port  
5. Installing the Modular Smart Switch  
HIGH port  
switches  
LOW port  
switches  
5.1 Selecting Ports for Your Equipment  
Printer and Plotter Sharing Applications  
Dual serial  
port module  
Unless otherwise specified, all print and plot data will automatically be routed  
to port 1. If you are automatically sharing a single printer or plotter, connect  
it to port 1. All ports have equal priority and data output is handled on a  
“first-come-first-served” basis.  
General Datacomm Applications  
For applications involving a central controlling PC, the PC should normally  
be connected to port 1 since data is routed to this port by default.  
OFF  
(0)  
5.2 Positioning the Modular Smart Switch  
Choose a central position for the Modular Smart Switch. This keeps cable  
lengths to a minimum.  
ON  
(1)  
1
2
3
4
5
6
7
8
9 10  
ON  
0
1
RS422  
RS232  
0
1
7 bits  
8 bits  
57k6 baud  
38k4 baud  
19k2 baud  
9k6 baud  
4k8 baud  
2k4 baud  
1k2 baud  
300 baud  
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
5.3 Cable Requirements  
You will need a suitable cable for each device that you wish to connect to the  
switch. Mechanical and electrical specifications for the cables are given in  
Appendix A (serial) and Appendix B (parallel).  
0
0
1
0
1
XON/XOFF-printer/plotter connections  
XON/XOFF-computer connections  
ETX/ACK handshake  
0
1
1
2 stop bits  
1 stop bit  
0
1
DTR/CTS handshake  
0
1
1
Even parity 0  
Odd parity  
No parity  
0
1
NOTE  
A great number of serial cables are available that are not suitable for use  
with your Modular Smart Switch. Do not assume that an existing cable is  
of the correct type because it has the correct connectors on each end or  
because it works between two other pieces of equipment. Always use  
the cabling recommended in this manual.  
Figure 4-3. Setting Serial Port Options and Protocols.  
Centronics parallel cables should be less than 22.9 ft. (7 m) long. If the  
parallel computer or printer is more than 22.9 ft. (7 m) from the switch, the  
cable may be susceptible to spurious pick-up such as that generated from  
switching on fluorescent lights. Reduce the cable runs or use a booster if you  
have problems.  
5.4 Connecting Devices to the Modular Smart Switch  
Switch off all computers and printers before making any connections to the  
Modular Smart Switch. Also, park any hard disks if you need to move any PCs  
to allow access.  
20  
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MODULAR SMART SWITCH  
MODULAR SMART SWITCH  
Plug in your cables, making sure that you are using the correct type of cable  
(see Appendixes A and B) and that you are connecting to the right type of  
port.  
MODE COM1:9600,N,8,1,P <enter>  
This sets the baud to 9600, no parity, 8 bits per character, and 1 stop bit on  
COM1. You may wish to put this in your computer’s AUTOEXEC.BAT file.  
You may wish to use the supplied software to enhance the speed and  
functionality of your serial port (refer to Chapter 7 for full details on the  
benefits of using the software utility).  
CAUTION  
Connecting to the wrong type of port could damage both the Modular  
Smart Switch and your computers and printers.  
ADMODE COM1:57600,N,8,1 <enter>  
5.5 Switching On  
If you have more than one port on your PC, make sure that your printout is  
sent to a port that is connected to the Modular Smart Switch. For IBM  
compatible PCs, DOS will prompt you to specify the printer port the first time  
you issue a print command. If you are using a parallel port (LPT1, LPT2, or  
LPT3), you can print directly without any further setup. If you are normally  
using a serial port to output print data, you may wish to redirect the parallel  
port data to output on the serial port, using the MODE command. The  
following example will set your PC to send all LPT1 data to COM1.  
Plug the power supply lead into the rear of the Modular Smart Switch. Plug  
the power lead into a suitable supply socket. Switch on at the supply. Switch  
on the Modular Smart Switch using the switch at the rear.  
The Power indicator (green) should come on and stay on. The Buffer  
Status indicators (red) should flicker for a few seconds while the unit self-  
tests, and then go out.  
MODE LPT1:=COM1:  
It is generally better to switch on all your devices together or switch on the  
Modular Smart Switch last.  
If you are going to plot/print from DOS, make sure that the computer  
cannot timeout if the buffer on the Modular Smart Switch becomes full. This  
could cause errors on your plots or an error message to be displayed on your  
screen. To avoid this, make sure that you have issued a MODE command with  
the P option set. If you wish to run your serial port at a high baud rate and  
make sure that no computer times out, you can use the MODE and ADMODE  
commands together. The ADMODE protocol will always override the MODE  
protocol. The following example would set COM1 to 57600 baud, no parity,  
8 bits, 1 stop bit, and no application timeout.  
5.6 Enabling Computers  
Computers Connected to Parallel Ports  
Parallel interfaces do not normally need to be configured. For IBM PCs  
running DOS, make sure that PC timeouts do not occur if the Modular Smart  
Switch’s buffer becomes full. This can be done using the MODE command  
as follows. Refer to your DOS manual for details.  
MODE COM1:9600,N,8,1,P <enter>  
ADMODE COM1:57600,N,8,1 <enter>  
MODE LPT1: , , P  
Computers Connected to Serial Ports  
NOTE  
If you are sending plot/print data from IBM compatibles using a serial  
port, make sure that your AUTOEXEC.BAT includes both the MODE (with  
P option) and ADMODE commands relevant to that port.  
Each computer must communicate with the Modular Smart Switch in the  
format expected by the port it is connected to. The baud rate, parity, bits per  
character, stop bits, and handshake format must be the same on the  
computer and the Modular Smart Switch port. Your computer instruction  
manual will tell you how to set up these parameters.  
For IBM PCs and compatibles, the MODE command is used to select the  
correct parameters. With the default option-switch settings and output on  
COM1, the MODE command is:  
22  
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MODULAR SMART SWITCH  
MODULAR SMART SWITCH  
5.7 Using the Modular Smart Switch  
5.9 Buffer Status Indicators  
Printer and Plotter Sharing Applications  
The buffer status indicators show the state of the internal buffer memory in  
the form of a bar graph:  
The Modular Smart Switch is now ready for use as a printer sharer for the  
printer attached to port 1. Data sent in from any computer will automatically  
be sent to this port.  
1
• ⁄4 Indicator—Buffer is over 1/4 full  
1
• ⁄2 Indicator—Buffer is over 1/2 full  
Users can print simultaneously, and the Modular Smart Switch will buffer  
the information until it can be sent to the default printer/plotter. All data  
from one source is treated as a single printable file until there has been a  
break in the transmission for more than the timeout period (see Section 4.1).  
3
• ⁄4 Indicator—Buffer is over 3/4 full  
F (full) Indicator—Buffer is completely full  
3
If the buffer often fills to the 4 level, consider purchasing additional  
memory for increased performance.  
If two or more printers/plotters are connected to the Modular Smart  
Switch, you will need the software (see Chapter 6) or software commands (see  
Chapter 9) to select between them. Other options and facilities are also  
detailed in these two sections.  
NOTE  
The Modular Smart Switch will always operate correctly even if the buffer  
becomes full. If you have any problems when the buffer memory is full,  
check the handshaking settings on your equipment and your cabling.  
General Datacomm Applications  
Once you are communicating correctly with the Modular Smart Switch, you  
can select between ports by sending ASCII command strings. In addition to  
the data destination, these ASCII command strings can be used to select the  
timeout period, “broadcast” data to several ports, and make/break permanent  
(no timeout) connections. The serial ports on the Modular Smart Switch are  
bidirectional. Refer to Chapter 7 for details on how to use the command  
strings and the connection options available.  
5.8 Port Indicators (1 to 12)  
The port indicators can be off, on, or flashing.  
Off—When a port indicator is off, nothing is being transferred into or out  
of that port and no data is available.  
On—The port indicator is on when data is available. If data has been sent  
in on a port, the activity light will remain on until the port has timed out  
(after no data has been sent for the timeout period).  
Flashing—While data is being transferred either into or out of the Modular  
Smart Switch, the activity indicator will flash.  
24  
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MODULAR SMART SWITCH  
MODULAR SMART SWITCH  
6.3 Command-Line Options  
6. Using the Control Software  
The control software supports a number of command line options that allow  
the utility to be installed and run in several different formats. They also allow  
a number of default settings to be changed and different hotkey  
combinations to be selected. Options are specified after a forward slash on  
the command line. Any number of options can be specified. For example,  
the following command line would install the utility for use in text modes  
with COM2 as the default port and the hotkey combination set to  
<CTRL><SHIFT>.  
The control software is located on the disk supplied with your Modular Smart  
Switch. It provides an easy and user-friendly way of operating the switch. It is  
designed for use on IBM compatible PCs using CGA, EGA, VGA, and  
monochrome adapters (it will also run on adapters that emulate the modes  
used by these adapters). Its primary function is to enable destination devices  
to be selected.  
Installing the utility in your PC’s memory as a “resident program” allows  
you to “pop up” the control software program at any time using a “hotkey”  
combination. The utility supports options that allow the software to run as a  
non-resident program from the DOS prompt (see Section 6.2) and while in  
the Microsoft Windows environment (see Section 6.4).  
ADMENU /T /C2 /H2  
The options available are summarized below. The default settings  
(shown in brackets) are assumed for all the options that are not specified.  
/U  
Deletes the utility from memory.  
/T and /G (/G default)  
(No default)  
6.1 Installing the Resident Software  
Copy the program ADMENU.COM from the disk to the current directory  
on your PC.  
At the DOS prompt, type ADMENU <enter>  
The /G option allows the resident software to be used in both text and  
graphics modes. When installed with the /G option, the software will  
occupy 22K of memory. Installing the software with the /T option allows the  
control software to be used in text modes only, and the memory requirement  
is reduced to 10K. The memory size used is confirmed in the installation  
message.  
The program will respond by printing an identification message. This  
command only needs to be issued once. You may therefore find it convenient  
to include it in your AUTOEXEC.BAT file. To invoke the ADMENU software,  
press these three keys together:  
<CTRL><ALT><SHIFT>  
/Lx and /Cx (/L1 default) x=1, 2, or 3  
These options specify the PC port that is displayed when the control software  
is initially invoked (either COM1, COM2, LPT1, LPT2, or LPT3). The  
number of the required port is specified after the letter C or L: C for serial, L  
for parallel. The port to be used can be specified once the software has been  
invoked using the PC PORT function and so these options are primarily for  
convenience only.  
NOTE  
You can change the hotkey combination used to invoke the ADMENU  
software if required (see Section 6.3).  
6.2 Running the Control Software from the DOS Prompt  
Copy the program ADMENU.COM from the disk to the current directory  
on your PC.  
/Hx  
(/H1 default)  
At the DOS prompt, type ADMENU /N <enter>.  
26  
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MODULAR SMART SWITCH  
MODULAR SMART SWITCH  
This option allows the hotkey combination that invokes the resident control  
software to be changed. There are 5 possible options. The desired option is  
selected by specifying the corresponding number after the letter H. The  
available hotkey combinations are as follows.  
To use HOTKEY within Windows, you must first install the control software  
in your computer’s memory. Do this before you run Windows, because once  
you are within Windows, resident programs cannot be loaded. You can then  
activate HOTKEY by clicking on HOTKEY.COM, HOTKEY.PIF, or an icon  
associated with these files.  
/H1 selects <CTRL><ALT>  
<SHIFT>  
/H2 selects <CTRL><SHIFT>  
/H3 selects <CTRL><ALT>  
/H4 selects <CTRL><ALT>  
/H5 selects <LEFT SHIFT>  
<RIGHT SHIFT>  
The control software can also be run as a non-resident utility from the  
Windows desktop. To do this, click on ADWIN.PIF or an icon associated with  
this file.  
NOTE  
For Windows 3 users, the easiest way to create an icon associated with  
HOTKEY.COM is to make a copy of a current file on the desktop and then  
to edit the properties of that file. For example, change the description to  
ADMENU and the group file command line to C:\WINDOWS\HOTKEY.  
COM.  
<SHIFT> can be either the left or the right shift key. The selected  
combination is confirmed in the installation message.  
/N and /R  
(/R default)  
These options allow the control software to be run as a non-resident utility.  
To do this, use the /N option. To install the menu as a resident program, use  
the /R option.  
6.5 Using the Control Software  
Invoking the control software will cause a menu to appear on the screen.  
You can select options from the menu using the <up> and <down> cursor  
keys and the <enter> key.  
/M  
(standard color default)  
• Use the <up> and <down> cursor keys to highlight the options in the  
menus.  
The /M ensures that the menu appears in mono mode. This option is  
provided for compatibility with certain types of monochrome screens found  
on some LAPTOPS and other computers. If the control software’s menu bars  
are faint or non-existent on your screen, then install the software using the  
/M option.  
• Use <enter> to select a highlighted option.  
• Use <escape> to quit from any menu or the application.  
6.4 Running the Control Software from within Microsoft® Windows®  
By using an additional utility (HOTKEY), you can invoke the resident control  
software within Windows. It is equivalent to pressing the hotkey combination  
that would normally be used to launch the control software.  
Hotkey-activated programs cannot be used from the Windows desktop,  
since Windows takes over full control of the keyboard, effectively locking  
other programs out. HOTKEY overcomes this problem by allowing the  
software to be invoked from an icon (or file name) while at the Windows  
desktop. HOTKEY remembers previous settings and retains these between  
applications. On some computers with additional memory, HOTKEY will run  
within a window. Switching to a full-screen application while within Windows,  
or quitting from Windows, will enable the hotkey combination to invoke the  
menu.  
28  
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MODULAR SMART SWITCH  
6.6 Main Menu  
MODULAR SMART SWITCH  
F. Destination Port—Indicates the port on the Modular Smart Switch that  
your PC is currently connected to. All data output from the currently  
selected PC port (G) will be routed to this destination port on the  
Modular Smart Switch.  
ADDER TECHNOLOGY  
A
B
C
D
E
G. PC Port—Indicates the port on your PC that the control software will use  
to send control commands to your Modular Smart Switch. Make sure that  
the port that is physically connected to the Modular Smart Switch is  
displayed in this box.  
ADMENU  
DESTINATION  
FILE TRANSFER  
DIRECT OUTPUT  
FUNCTIONS  
H. Mode—Indicates whether normal mode or file-transfer mode is  
currently selected. In normal mode, a dash (-) will be displayed. In file-  
transfer mode, a flashing arrow will be displayed. The mode in use is set  
automatically when you select a destination port using the  
OPTIONS  
PORT 2 LPT1  
DESTINATION (normal mode) or FILE TRANSFER option.  
<ESC> TO QUIT  
6.7 Selecting a Destination Printer, Plotter, or Modem  
The control software initially assumes that the Modular Smart Switch is  
connected to the PC with a parallel link to LPT1. (Other default ports can  
be specified using the /L or /C command-line option—see Section 6.3.)  
If a different parallel PC port has been connected (LPT2, LPT3) or one of  
the serial PC ports (COM1 or COM2), then you must first select that port—  
see Section 6.10.3. Where several links are made to the same PC, then you  
first need to make sure that you have selected the PC port that you wish to  
use to print data.  
F
G
H
Figure 6-1. Main Menu.  
With the dialog box displaying the correct PC port and DESTINATION  
highlighted, press <enter>. A new box will appear as shown below. Enter  
the desired destination port number, then type <enter>. All subsequent print  
data that is sent out on the currently selected PC port will be routed to the  
device attached to the specified destination port on the Modular Smart  
Switch. For example, selecting port 1 will send data to the device attached  
to port 1 on the Modular Smart Switch. The currently selected routing will  
be displayed on the main menu.  
A. Destination—Used to connect your computer to the required printer,  
plotter, modem, or other device (see Section 6.7).  
B. File Transfer—Used to connect through to other computers and set the  
Modular Smart Switch to file-transfer mode. This option should only be  
used to establish links for file-transfer purposes—use the DESTINATION  
option for all other applications (see Chapter 8). File transfer is only  
available on serial ports.  
C. Direct Output—Used to output characters and control codes directly  
from your keyboard (see Section 6.8).  
D. Functions—Allows you to clear data, form feed the printer or end a long  
timeout (see Section 6.9).  
E. Options—Used to select the number of copies, timeout period, and the  
PC port that the menu is to control (see Section 6.10).  
30  
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MODULAR SMART SWITCH  
MODULAR SMART SWITCH  
6.8 Direct Output of Typed Keyboard Characters  
Normal keyboard characters and control characters can be sent to the printer  
using the “Direct Output” option. In the keyboard characters box, all  
characters typed will be sent directly to the printer except <up>, <down>, and  
<escape>. Control characters such as those to set condensed or bold printing  
can be specified in hexadecimal ASCII format. In the hexadecimal ASCII  
characters box, the specified character is sent when you press <enter>.  
ADDER TECHNOLOGY  
ADMENU  
DESTINATION  
FILE TRANSFER  
DIRECT OUTPUT  
FUNCTIONS  
DESTINATION  
OPTIONS  
ADDER TECHNOLOGY  
ADMENU  
ENTER  
DESTINATION  
PORT NUMBER  
PORT 1 COM1  
<ESC> TO QUIT  
DESTINATION  
FILE TRANSFER  
DIRECT OUTPUT  
(1 TO 12)  
FUNCTIONS  
OPTIONS  
DIRECT OUTPUT  
KEYBOARD  
CHARACTERS  
PORT 1 COM1  
<ESC> TO QUIT  
Figure 6-2. Selecting a Printer.  
HEXADECIMAL  
• Use <esc> to abort and quit to the main menu, <enter> to confirm.  
ASCII CHARACTERS  
• Enter the destination (the port on the Modular Smart Switch that is  
connected to the required printer, plotter, or modem.  
• Valid port identifiers are 1 to 12, depending on how many ports you have  
installed.  
Figure 6-3. Direct Output Menu.  
Use <esc> to quit to the main menu.  
NOTE  
Characters such as line feeds are displayed using an unusual set of non-  
alphanumeric characters.  
32  
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MODULAR SMART SWITCH  
When in the functions menu, use the arrows to select END OF FILE and then  
press <enter>. The dialog box will respond with an END OF FILE message  
for a few seconds. The END OF FILE function can also be used to end long  
timeouts.  
6.9 Using the Functions Menu  
To enter the functions menu, use the <up> and <down> cursor keys on the  
main menu to highlight FUNCTIONS, and press <enter>. The functions  
menu now allows you to send form feeds, clear unwanted data, and end long  
timeouts.  
6.10 Setting the Options  
To enter the options menu, use the <up> and <down> cursor keys on the  
main menu to highlight OPTIONS, and press <enter>. The options menu  
now allows you to select multiple copies, change the timeout, and change  
the PC port.  
ADDER TECHNOLOGY  
ADMENU  
DESTINATION  
FILE TRANSFER  
DIRECT OUTPUT  
ADDER TECHNOLOGY  
ADMENU  
FUNCTIONS  
OPTIONS  
DESTINATION  
FILE TRANSFER  
DIRECT OUTPUT  
FUNCTIONS  
PORT 1 COM1  
FUNCTIONS  
<ESC> TO QUIT  
FORM FEED  
OPTIONS  
CLEAR DATA  
END OF FILE  
PORT 1 COM1  
OPTIONS  
<ESC> TO QUIT  
COPIES  
Figure 6-4. Functions Menu.  
Use <esc> to quit to the main menu.  
6.9.1 SENDING A FORM FEED  
This is a convenient way of causing a printer to take a new page, without  
having to go to the printer and press the form-feed button. In the functions  
menu, use the <up> and <down> cursor keys to select FORM FEED and then  
press <enter>. The dialog box will respond with FORM FEED SENT for a few  
seconds.  
TIME OUT  
PC PORT  
Figure 6-5. Options Menu.  
Use <esc> to quit to the main menu.  
6.10.1 MULTIPLE COPIES  
The Modular Smart Switch can generate multiple copies automatically.  
Simply select the COPIES option, enter the number of copies required (up to  
255) in the entry box and press <enter>. Send the document once, and when  
it has timed out (no more data sent for at least 16 seconds or the timeout  
period), the Modular Smart Switch will commence printing the extra copies.  
The entire document must be less than the buffer memory in the Modular  
Smart Switch; otherwise only one copy can be produced.  
6.9.2 CLEARING UNWANTED DATA  
To delete all the data that has been sent from the current PC port, select the  
CLEAR DATA option and press <enter>. A box will appear requesting  
confirmation. Type Y if you wish to delete all data, or N or <escape> if you  
don’t. This command will not affect any data sent from a different computer.  
6.9.3 ENDING LONG OR INFINITE TIMEOUTS  
When an infinite (OFF) timeout has been set, an end of file instruction needs  
to be sent to the Modular Smart Switch to allow other users to access the  
currently selected device. The END OF FILE function can be used to do this.  
34  
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MODULAR SMART SWITCH  
MODULAR SMART SWITCH  
6.10.2 CHANGING THE TIMEOUT  
7. Serial Port Control Utility  
The timeout period can be varied from the default of 16 seconds to any value  
between 1 and 255 seconds, or it can be permanently off. To do so, select  
the TIMEOUT option and type the required value into the entry box. Press  
<enter> to return to the options menu. To return to the default value of  
16 seconds, press <escape>.  
The control software allows serial ports on IBM compatible PCs to be run at  
the high baud rates supported by the Modular Smart Switch. The utility can  
be used to control COM1 or COM2 and supports a wide range of protocols.  
The time-saving advantages of running serial ports at higher baud rates can  
be quite dramatic, and the control software makes sure that the correct  
protocol is used regardless of the settings on the application program.  
6.10.3 SELECTING A PC PORT  
If the correct PC port is not shown on the main menu (G in Figure  
6-1), then use the PC PORT option to select this. Highlight the PC PORT  
option and type <enter>. Use the <up> and <down> cursor keys to select  
the desired port (highlighted) and then press <enter>. The PC port you  
have selected will now be displayed.  
Although DOS will normally only support baud rates up to 9600, most PCs  
are capable of running at much higher speeds of 19,200, 38,400, or 57,600  
baud. A number of high-baud-rate utilities are available that act like the  
DOS MODE command. But these can be of little practical use, since many  
application programs change the baud rate and protocol when they run.  
The control software overcomes this problem by preventing application  
programs from changing the baud rate or protocol of the serial port being  
controlled. This has two major advantages. First, the user does not need to  
worry about setting the baud rate and protocol in the application program.  
Second, high baud rates can be used for plotting from packages that would  
normally only support lower baud rates.  
NOTE  
The control software defines the routing from the selected port on your  
PC—it does not set the port that your software will use for output.  
To run the control software, copy the program ADMODE.COM from  
the utility disk to a suitable directory on your PC. At the DOS prompt,  
type a command in the following format.  
ADMODE COMn: baud, parity, databits, stopbits  
You only need to include a parameter after baud if it needs to be changed  
from the default values shown in Table 7-1. The minimum command syntax  
is:  
ADMODE COMn: baud  
Example  
To set serial port 1 (COM1) to 38400 baud, 8 data bits, 1 stop bit,  
and no parity, use the following command.  
ADMODE COM1:38400,N,8,1 <enter>  
High-Baud-Rate Limitations  
In practice, almost all modern PCs will support baud rates of 38,400.  
However, a number of PCs that we tested were not able to support baud rates  
of 57,600 because of the design of their serial ports. If you have problems  
with particular PCs, try reducing the baud rate.  
36  
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MODULAR SMART SWITCH  
Increasing the baud rate of serial connections reduces the maximum cable  
lengths. As a rule of thumb, doubling the baud rate halves the maximum  
distance. At 57,600 baud, try to limit the cable lengths to about 50 ft. (15 m).  
OR:  
b) The Fast Printing Direct to Port option is switched off within Windows 3.1.  
This can be found within the CONTROL PANEL  
PRINTERS CONNECT window.  
If you have problems using the control software, reduce the baud rate. In  
practice, 38400 baud is a “safe” setting for most applications.  
Table 7-1. Parameter Settings.  
Parameter  
Options  
Entered as  
Default  
n
1 or 2  
COM1:, COM2:  
300, 1200, 2400,  
baud  
300, 1200, 2400,  
4800, 9600, 19200, 4800, 9600, 19200,  
38400, 57600  
odd, even, none  
7 or 8  
38400, 57600  
O, E, N  
7, 8  
parity  
N
8
data bits  
stop bits  
1 or 2  
1, 2  
1
Using the Control Software with Windows Version 3.1  
Windows version 3.1 supports fast printing directly to a port. If you are using  
Windows 3.1 and printing to a serial (COM) port, interaction problems can  
occur with the control software program if Windows is not set up as detailed  
below.  
If you are using the control software program to control the baud rate and  
protocol of COM1 or COM2 and you are using Windows 3.1, make sure that:  
EITHER:  
a) The COM port is set up within Windows 3.1 to use the same baud rate and  
protocol as that used by the control software. (You can change the COM port  
protocol using the Control Panel utility within Windows 3.1. Baud rates of  
38400 and 57600 can be selected by typing these values into the baud-rate  
selection box.)  
38  
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MODULAR SMART SWITCH  
8. Using the Modular Smart Switch  
to Transfer Files  
ADDER TECHNOLOGY  
ADMENU  
DESTINATION  
The Modular Smart Switch can be used to transfer files between PCs  
FILE TRANSFER  
connected to the serial ports. This can be done using standard file-transfer  
®
DIRECT OUTPUT  
FUNCTIONS  
OPTIONS  
software such as Fastlynx, Laplink, ProComm +, or Kermit.  
FILE TRANSFER  
NOTE  
ENTER TARGET  
PORT FOR DATA  
EXCHANGE  
The file-transfer facility can only be used between computers that are  
connected to the Modular Smart Switch via an RS-232 or RS-422 serial  
link.  
PORT 1 COM1  
<ESC> TO QUIT  
8.1 Transferring Files Between IBM® Compatible PCs  
(1 TO 12)  
To transfer files between two PCs connected to the Modular Smart Switch,  
follow the steps below.  
A
B
C
Figure 8-1. Main Menu.  
NOTE  
A=The port on the Modular Smart Switch that is connected to the computer  
that you wish to exchange files with.  
Before you use your Modular Smart Switch to transfer files, make sure  
that you have installed the control software on both PCs.  
B=The port on your computer that is connected to the Modular Smart  
Switch.  
1. Activate the control software on the first PC.) You can activate the control  
software by using the hotkey combination or by running the program  
HOTKEY.COM from the DOS prompt or from within a batch file.)  
Select the File Transfer option on the main menu. Enter the serial  
port on the Modular Smart Switch that is connected to the second PC.  
The main menu will be displayed as shown in Figure 8-1.  
C=A flashing arrow to indicate that the Modular Smart Switch is in “file-  
transfer mode.”  
2. Boot up the file-transfer software on the first PC.  
3. Activate the control software on the second PC. Select the File Transfer  
option on the main menu. Enter the port on the Modular Smart Switch  
that is connected to the first PC.  
4. Boot up the file-transfer software on the second PC.  
5. Follow the instructions for your file-transfer software.  
6. Quit from the file transfer software on both PCs.  
When using file-transfer software, make sure that you have selected the  
target PC before you boot up your file transfer software. Failing to do this  
could cause unwanted data to be sent to your printer/plotter. To make sure  
that this does not occur it is advisable to activate the control software and your  
file-transfer software from a batch file. This will cause the control software to  
appear automatically before you boot your file-transfer software. A suitable  
batch file for Kermit would be as follows:  
40  
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MODULAR SMART SWITCH  
REM The next line activates ADMENU  
8.4 General Hints and Tips  
1. Always use the control software when using file-transfer software:  
Many packages such as Laplink Pro will not operate without the  
control software installed.  
HOTKEY  
REM The next line activates the file-transfer software  
KERMIT  
2. File transfer requires a protocol of 8 bits per character, 1 stop bit, no  
parity, and hardware handshaking. When using RS-232 with hardware  
handshaking, make sure that pins 4 and 5 are connected on the Modular  
Smart Switch end of your computer cable. XON/XOFF handshaking may  
also be used, but overall performance is reduced.  
8.2 Using the Control Software with File-Transfer Software  
The control software supplied with your Modular Smart Switch should be  
used together with file transfer software. The control software allows you  
to increase the baud rate for all normal printing and plotting operations,  
so you can use the higher baud rates that are supported on many file transfer  
programs without having to reconfigure the ports on your Modular Smart  
Switch. Using higher baud rates will considerably reduce the time taken  
to transfer files. For more details on the use of the control software,  
see Chapter 7.  
3. When using PC-to-PC file transfer, use similar baud rates on both PCs.  
For example, combinations of 57600 baud and 38400 baud will be  
reliable, whereas combinations of 57600 and 9600 are likely to be  
unreliable. If in doubt, use the same baud rate on both PCs. (Similar  
baud rates are required because most file-transfer programs do not  
support handshaking—they do not allow the rate of data flow to be  
controlled.)  
8.3 Transferring Data Between PCs Not Compatible with IBM  
To transfer files between computers not compatible with IBM, you will need  
to send a software command from each computer to make sure that the data  
is routed correctly. For maximum compatibility, you are advised to send a  
software command with the format shown below (“port” is a port number  
from 1 to 12):  
<PM CONNECT port SOFTWARE:SLEEP TIMEOUT:2>  
The SOFTWARE:SLEEP and TIMEOUT:2 parts of this command are  
not strictly necessary for certain types of file transfer. For many file-transfer  
programs such as Kermit, it is adequate to send a single connection command  
from one of the computers to establish a bidirectional link. For example,  
when using Kermit to exchange files between a PC and a Macintosh, sending  
the following command from the PC would establish a suitable bidirectional  
link.  
<PM CONNECT port TIMEOUT:OFF>  
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9.2 Connect Command  
9.2.1 SELECTING A DESTINATION PORT  
9. Software Commands  
By default, the Modular Smart Switch automatically sends all data to port 1.  
To send data to a different port or route back to port 1, use the following  
command:  
9.1 Introduction  
The Modular Smart Switch can be controlled by sending software commands  
to it from any computer (serial or parallel). These commands let you change  
to switch between ports and give access to some more advanced features of  
the Modular Smart Switch. The control software (see Chapter 6) for use with  
IBM PCs automatically generates the required software commands. This  
section gives the format and purpose of each command.  
<PM CONNECT port>  
where “port” represents a port number from 1 to 12.  
The new destination will now be used for all subsequent data sent into the  
port that gave the command until either a new command is sent, or the  
Modular Smart Switch is powered off.  
All software commands have the following format:  
<PM command {parameters}>  
9.2.2 PRINTING SEVERAL COPIES  
If several copies of a document are required, you do not need to send the file  
repeatedly. The connect command allows up to 255 copies to be generated  
from a single file. The format of the multiple copy command is:  
The command must begin with the three characters <PM and end with a  
single character >. In the following text, UPPER CASE is used to represent a  
keyword, for example, CONNECT. Anything that is in {brackets} is optional.  
Text that is in lower case should be replaced by the keyword or option that it  
represents.  
<PM CONNECT port:copies>  
To print three copies of a file on the printer/plotter attached to port 1, the  
command becomes:  
For example, the command to connect to channel 2 (serial) would be as  
follows:  
<PM CONNECT 1:3>  
<PM CONNECT 2>  
A string of characters will only be recognized as a command if all the  
characters are correct, thus making confusion with normal text extremely  
unlikely. Software commands should be sent to the Modular Smart Switch as  
a string of ASCII characters. A suitable way of doing this would be to create a  
file containing the required command, and “print” it when needed, though  
there are many other possibilities such as inserting the required selection  
string at the top of a word processor document (refer to your computer  
manuals). Users of IBM compatible computers can create batch files that  
send software commands (see Section 9.5 for notes on how to create these).  
NOTE  
The extra copies will not begin to be printed until the Modular Smart  
Switch has accepted the whole file into its memory. This is normally  
when no further data has been received for the timeout period, which is  
initially set to 16 seconds. The timeout may be altered or switched off if  
necessary (see Section 9.2.4). Alternatively, an end-of-file command will  
tell the Modular Smart Switch that it now has the whole file (see Section  
9.4). If the file is too large to fit inside the buffer, then you cannot print  
more than one copy.  
9.2.3 BROADCASTING DATA TO SEVERAL DEVICES  
Items in a software command can be separated by spaces, tabs, line feeds, or  
form feeds; however, only one of these may be used between each item. In  
the following sections, references to single spaces apply equally to single tabs,  
single line feeds, and single form feeds.  
To set the Modular Smart Switch to broadcast data to several ports  
simultaneously, use the CONNECT command and specify a list of ports that  
the data is to be sent to (up to 4 in total). Separate the port numbers with a  
space. The multiple copy CONNECT command can also be repeated in this  
way. For example, to print two copies on port 3 and one copy on port 1 of  
every file sent from the computer, issue the following command:  
<PM CONNECT 3:2 1>  
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9.2.4 VARYING THE TIMEOUT PERIOD  
<PM CONNECT port SOFTWARE:DISABLE>  
The timeout sets the length of time that the output port remains dedicated  
to the input port once the incoming data has ceased. It can be set to any  
number of seconds between 1 and 255, or it can be switched off. With the  
timeout off, the output channel remains constantly dedicated to the input  
channel until an end of file command (see Section 9.4), or a new connect  
command is sent. The timeout remains as set until it is changed again,  
or the Modular Smart Switch is powered off.  
9.2.6 REMOVING LINE FEEDS AT END OF SOFTWARE COMMANDS  
When programming applications such as DBASE to automatically send data to  
a specific printer, you might want to remove linefeed and carriage-return  
characters that are automatically inserted by the application at the end of the  
software command. To do this, add an “ignore” instruction to the software  
command as follows:  
To change the timeout, a connect command is sent with the timeout  
option specified after the required destination port, as follows:  
<PM CONNECT port IGNORE>  
When the Modular Smart Switch receives such an instruction, it will delete  
the line feed (CR or LF or both) following the software command.  
<PM CONNECT port TIMEOUT:value>  
The timeout value is either a number 1 to 255 or the word OFF.  
For example, if a computer requires uninterrupted use of the printer  
connected to port 1 until further notice, the command below would be sent:  
9.3 Clear Command  
The clear command allows a computer to delete any data that has been sent  
into the Modular Smart Switch that has not yet been printed. As with all  
software commands, this only affects the data from the computer that sends  
the command. The format is:  
<PM CONNECT 1 TIMEOUT:OFF>  
9.2.5 DISABLING SOFTWARE COMMANDS  
<PM CLEAR>  
When communicating with another computer using a file-transfer protocol  
such as that used by Laplink or Xmodem, you can temporarily turn off the  
command interpretation while files are being transferred. This is because  
some of these protocols expect a checksum character to be sent back as an  
acknowledgement after a block of data has been sent. If this character  
happens to be the start character (<) of a software command, a delay can  
occur that may cause the transfer software to time out. To make sure that  
this does not happen, you can set the Modular Smart Switch to ignore  
software commands during file transfer. To do this, use the “software sleep”  
command. Once a “software sleep” command has been sent, the Modular  
Smart Switch will not interpret new commands until the data transfer has  
timed out. This will occur after no data has been sent for the timeout period.  
To set “software sleep” mode, send the following command:  
9.4 End-of-File Command  
Sending the end-of-file command terminates the present input file. It is used  
when the timeout option has been set “off,” since it will allow other  
computers access to the printer. If multiple copies are required, the end-of-  
file command indicates the end of the document. A new command will also  
automatically terminate the present input file. The format used for the end-  
of-file command is as follows:  
<PM EOF>  
9.5 Creating Batch Files to Send Commands (IBM Compatible PCs)  
<PM CONNECT port SOFTWARE:SLEEP>  
On IBM compatible PCs, batch files are a convenient way to send commonly  
used software commands. To create batch files, proceed as follows:  
To restore normal software command interpretation, send the following  
command when the data has timed out.  
At the DOS prompt, type:  
<PM CONNECT port SOFTWARE:ENABLE>  
COPY CON: {name}.TXT [enter]  
<PM CONNECT {channel number} >[function key 6]  
Software command interpretation can also be permanently disabled using  
the following command. Once this command has been issued, no software  
commands will be interpreted until the Modular Smart Switch has been reset  
(by switching the power off).  
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MODULAR SMART SWITCH  
9.6 Sending Default Start-of-Day Destination Ports  
At the start of each day, each port will be routed through to port 1. However,  
for IBM compatible PCs, individual start-of-day destinations can be set for  
each computer. To do this, create a text file containing the desired selection  
command (see Section 9.5) and modify your AUTOEXEC.BAT file to send  
this command when your computer powers on. For example, by including  
the line “TYPE CONNECT2.TXT>COM1:” in your PC’s AUTOEXEC.BAT file  
(after copying CONNECT2.TXT from the utility software disk to a suitable  
directory on your PC), you can set the start-of-day default port for your  
computer to be number 2.  
Where {name} is the name of the batch file that you are going to create and  
{channel number} is the number of the port that you are going to connect to.  
For example:  
COPY CON: CONNECT2.TXT [enter]  
<PM CONNECT 2>[function key 6][enter]  
No spaces should be typed after the close angle bracket and before the  
function key 6 is pressed. When function key 6 has been pressed, a ^Z will  
appear on the screen at the end of the line. When the enter key is pressed,  
the screen will display:  
1 File(s) copied  
This indicates that a file {name}.TXT has been created that contains the  
software command text. It is not normally possible to use a word processor to  
create this file, since most word processors insert a line feed and carriage  
return at the end of each line. A file created with these extra characters could  
upset your printouts by inserting a blank line at the top of your printout page.  
This could cause laser printers to output a blank page and label printers to be  
offset by one line.  
At the DOS prompt, type:  
COPY CON: {name}.BAT [enter]  
TYPE {name}.TXT > {pc printer port}: [function key 6] [enter]  
Where {name} is the name of the batch file that you are going to create and  
{pc printer port} is the port that you wish to be routed to the required  
printer—COM1, COM2, LPT1, LPT2, or LPT3. For example:  
COPY CON: CONNECT2.BAT [enter]  
TYPE CONNECT2.TXT>COM1: [function key 6][enter]  
As before, the screen will display “1 File(s) copied,” which indicates that a  
batch file {name}.BAT has been created containing the text “TYPE  
{name}.TXT>{pc printer port}:.”  
To send the software command that you have created in {name}.TXT, type  
the batch file name at the DOS prompt. The above procedure can be used to  
create a batch file to send any software command to any of your PC’s ports.  
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MODULAR SMART SWITCH  
10.4 Problems Interfacing Serial Devices  
10. Troubleshooting  
Most problems experienced with connecting serial devices are caused by  
incorrect cabling or incorrect handshake/protocol settings. Do not assume  
that, because a cable has the correct connectors and works between two other  
devices, it will work when connected to the Modular Smart Switch. Always use  
the cabling specified in this manual (see Appendixes A and B). Incorrect  
cabling may cause many different problems, such as:  
The Modular Smart Switch is designed to a high standard and all units are  
fully tested before leaving the factory. There are no user-serviceable parts.  
If a fault persists, please contact technical support.  
10.1 Self-Test at Power-On  
• No data transmission  
The Modular Smart Switch automatically tests its basic operation when it  
powers on. The buffer indicators flash for a few seconds while the test is  
being conducted and go out when the test has passed. If the buffer indicators  
do not flash or do not go out, then there may be a problem—consult  
technical support.  
• Loss of data, corrupted prints and plots  
• Unreliable file transfer  
10.5 Serial Interfaces—No Data Transmitted through the Switch  
Check that you can send data between your devices using a direct connection.  
If you can’t, check your devices. If you can, connect the Modular Smart  
Switch and try sending a small amount of test data.  
10.2 Parallel Interfaces—No Data Transmitted through the Switch  
If you have problems transmitting data through the switch using parallel  
interfaces, make sure that the direction (input or output) has been set  
correctly—see Section 4.2. If you have any problems in transmitting to  
parallel ports, do not use the automatic in/out detection setting, because  
this is not guaranteed to work with all printers.  
If the input channel indicator comes on, then no data is being sent into the  
switch—check the cable between your PC and the Modular Smart Switch, and  
check that you are sending the data from the correct port on your computer.  
The channel indicators show whether data is being routed correctly from  
one port to another.  
If the channel indicator flickers or comes on, then data is being transferred  
into the Modular Smart Switch.  
If no data appears to be transmitted out from the Modular Smart Switch,  
then check the cable between the switch and your output device.  
10.3 Parallel Interfaces—Corrupted, Extra, or Lost Data  
Problems with corrupted data when using parallel communication are rare.  
When problems do arise, they are mostly cabling problems. Avoid using  
ribbon cables. Use shielded cables and keep the length to 22.9 ft. (7 m)  
or less where possible. Problem cables can cause occasional data corruption  
and spurious page feeds on laser printers.  
If the channel indicators go out after the timeout period (usually 16  
seconds), then all the data has been sent out of the switch. If nothing appears  
to have been received on your output device, then check the protocol (a  
protocol problem often causes the data to be changed into a stream of null  
characters).  
10.6 Serial Interfaces—Corrupted Data  
The most common cause of corrupted data when using serial interfaces is a  
handshake problem. If you experience corrupted data when using serial  
ports, check that the protocols set on your equipment are the same as those  
set on the Modular Smart Switch. If you are using hardware handshake,  
check that the hardware flow-control lines are connected on your cable.  
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10.7 Merged Printouts  
If the output from one computer has been printed in the middle of that from  
another, you will probably need to increase the timeout period. When no  
data has been sent from one computer for the timeout period (by default  
16 seconds), the Modular Smart Switch will allow another computer to start  
printing. To change the timeout period, use the control software (see Section  
6.10.2) or send a software command (see Section 9.2.4). The default timeout  
period is set using the option switches on the main board (see Section 4.1).  
MODULAR SMART SWITCH  
Appendix A: Serial Ports  
A.1 RS-232 and RS-422 Pin Assignments  
The serial ports on the Modular Smart Switch use DB25 connectors. The  
following table lists RS-232 and RS-422 pin assignments and signal  
descriptions. Those pins not appearing in the table are not used.  
Table A-1. DB25 Serial Pinouts.  
10.8 Print Data Transmitted but File Transfer Fails  
If you can print normally using your PC’s serial port but file transfer fails,  
check the following:  
Pin Description  
RS-232 RS-422 In/Out  
1
2
3
4
5
Protective ground (shield)  
EARTH  
TXD  
EARTH  
• Make sure that the control software is installed.  
• Make sure that the protocol is set to 8 bits, 1 stop bit, no parity.  
Transmitted data (data out)  
Received data  
Output  
Input  
Output  
Input  
• For hardware handshake, make sure that pins 4 and 5 are connected  
on the Modular Smart Switch end of the computer serial cable.  
RXD  
RTS  
Request to send—Always held HIGH  
Clear to send—flow control in  
(hardware handshake)  
CTS  
7
Signal ground  
GND  
DTR  
20  
Data terminal ready—flow control out  
(hardware handshake)  
Output  
9
Flow control out (-ve)—hardware  
handshake  
HSOUT - Output  
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Table A-1 (continued). DB25 Serial Pinouts.  
IBM PC end  
25-Pin socket connector  
Modular Smart Switch end  
25-Pin socket connector  
Pin Description  
RS-232 RS-422 In/Out  
RXD  
3
10  
Flow control out (+ve)—hardware  
HSOUT + Output  
2
3
5
6
7
handshake  
TXD  
2
11  
12  
13  
15  
Received data (-ve)  
Received data (+ve)  
Transmit data (-ve)  
RXD -  
RXD +  
TXD -  
HSIN -  
Input  
Input  
Output  
Input  
DTR  
20  
GND  
7
CTS  
5
Flow control in (-ve)—hardware  
handshake  
4
16  
25  
Flow control in (+ve)—hardware  
handshake  
HSIN +  
TXD +  
Input  
Figure A-1. IBM PC/XT Serial Cable Pinning.  
If you already have a cable that works directly between your IBM PC and  
serial printer, it may be suitable for use as the input cable to your Modular  
Smart Switch.  
Transmit data (+ve)  
Output  
A.2.2 RS-232 CONNECTIONS TO IBM AT AND COMPATIBLES  
A.2 Connecting to Computers—RS-232 Connections  
The IBM AT and compatibles provide a DB9 connector for the serial port.  
The cable required to connect to the Modular Smart Switch is wired as shown  
in Figure A-2.  
RS-232 serial ports on computers tend to vary considerably. The standard  
recommends a DB25 connector, but some machines, such as the IBM AT and  
compatibles, use a DB9 connector. Computer ports intended for connection  
to a modem are not configured like those intended for connection to a serial  
printer. Because of all these variables, a “standard” RS-232 cable does not  
exist.  
NOTE  
You might need to refer to the documentation supplied with your  
computer to establish the type of cable required. The following  
specifications may help you decide on the required cable.  
A.2.1 RS-232 CONNECTIONS TO IBM PCS AND COMPATIBLES  
The IBM PC and its compatibles provide a parallel port and (usually) an RS-  
232 serial port. Both use a DB25 connector. However, the parallel port is  
normally a socket (female) connector, and the serial port is normally a plug  
(male) connector. The cable wiring required for connection to a serial port  
on the Modular Smart Switch is shown in Figure A-1.  
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A.4 Connecting to Modems  
The cable shown in Figure A-4 can be used to connect to most standard  
modems. Do not connect additional lines.  
IBM AT end  
9-Pin socket connector  
Modular Smart Switch end  
25-Pin socket connector  
TXD  
2
2
3
5
6
8
RXD  
Modem end  
25-pin plug connector  
3
Modular Smart Switch end  
25-Pin socket connector  
GND  
7
1
2
1
2
DTR  
20  
CTS  
3
3
5
4
4
4
5
5
Figure A-2. IBM AT Serial Cable Pinning.  
7
7
A.3 Connecting to Printers  
20  
20  
Most serial printers provide a standard DB25 connector for serial data. The  
required cable wiring is shown in Figure A-3. This wiring configuration is  
®
®
®
suitable for many popular printers such as HP LaserJet , QMS, Brother ,  
Figure A-4. Cable Pinout for Modems.  
®
and Epson (with serial-port card).  
Modular Smart Switch end  
25-Pin socket connector  
Printer end  
25-pin plug connector  
TXD  
2
3
2
RXD  
3
CTS  
5
20  
5
6
DTR  
20  
6
GND  
7
7
Figure A-3. Cable Pinout for Serial Printers.  
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A.5 Connecting to Plotters  
A wide range of different pin configurations are used on plotter serial ports.  
The following cable can be used for most plotters including those  
manufactured by Hewlett Packard and Roland. Notable exceptions are  
Calcomp plotters, which need a “straight-through” cable shown in Figure  
A-4. If you have a cable that currently works between your PC and plotter,  
then this can be used between the Modular Smart Switch and your plotter  
with the addition of an adapter.  
MODULAR SMART SWITCH  
A.6 Connecting to NEC Spinwriter  
®
The NEC Spinwriter series of printers also provide a DB25 socket connector  
for serial data. However, their “printer ready” flow-control signal is output on  
pin 19 (unlike most printers, which output this signal on pin 20). Suitable  
wiring is as shown in Figure A-6.  
NEC Spinwriter end  
Modular Smart Switch end  
25-Pin socket connector  
25-pin plug connector  
2
3
3
7
3
2
Modular Smart Switch end  
25-Pin socket connector  
Plotter end  
25-pin plug connector  
TXD  
2
19  
7
3
2
RXD  
3
CTS  
5
5
20  
5
20  
6
6
DTR  
8
20  
6
GND  
7
7
Figure A-6. NEC SpinWriter Serial Cable.  
Figure A-5. Plotter Cable Adapters.  
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A.7 Connecting to DEC™ LN03 Laser Printer  
A.8 RS-422 Cables  
The LN03 outputs its “printer ready” signal via pin 11, and so the wiring for  
the serial data cable is slightly different from those shown earlier. Switch  
bank 2, switch number 6, on the LN03 should be set to ON. This ensures that  
the “printer ready” signal is HIGH when ready and LOW when not ready, and  
not vice versa.  
The pins and connector types used for RS-422 communication vary widely  
between devices. Standard cables therefore do not exist. Connect the cable  
as shown in Figure A-8. For systems using XON/XOFF handshaking, only  
RXD +, RXD -, TXD +, and TXD - need to be connected.  
Modular Smart Switch end  
25-Pin socket connector  
Communicating  
device  
Modular Smart Switch end  
25-Pin socket connector  
DEC LN03 end  
25-Pin plug connector  
HSOUT-  
9
-ve  
+ve  
-ve  
+ve  
-ve  
+ve  
-ve  
+ve  
Flow control  
in  
HSOUT+ 10  
RXD- 11  
RXD+ 12  
HSIN- 15  
HSIN+ 16  
TXD- 13  
TXD+ 25  
2
3
3
2
Transmitted  
data out  
5
11  
7
Flow control  
out  
7
Received  
data in  
20  
6
Figure A-7. DEC LN03 Serial Cable Pinning.  
Figure A-8. RS-422 Cable Pinouts.  
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Table B-1. DB25 Parallel Connector Pinouts.  
Appendix B: Parallel Ports  
Pin  
Name  
Input from Computer Output to Printer  
B.1 Parallel Pin Assignments  
Each parallel port uses a DB25 socket connector, similar to the one on an  
IBM PC, PC/XT, or AT. Figure B-1 shows the pin numbers as viewed from  
the rear of the Modular Smart Switch.  
1
STROBE  
INPUT  
OUTPUT  
2-9  
10  
DATA 0 to 7  
ACKNOWLEDGE  
BUSY  
INPUT  
OUTPUT  
OUTPUT  
no connection  
INPUT  
13  
1
11  
OUTPUT  
12  
PAPER END  
SELECT  
OUTPUT low  
OUTPUT high  
no connection  
OUTPUT high  
no connection  
no connection  
ground  
no connection  
no connection  
no connection  
no connection  
OUTPUT high  
OUTPUT low  
ground  
13  
25  
14  
14  
AUTOFEED XT  
ERROR  
Figure B-1. DB25 Parallel Connector.  
15  
16  
INIT  
17  
SELECT IN  
SIGNAL GROUND  
18-25  
The cables need to have a DB25 connector for connecting to the Modular  
Smart Switch. If possible, the length should be kept below 22.9 ft. (7 m) to  
reduce interference.  
62  
63  
 
MODULAR SMART SWITCH  
B.2 Cable for IBM PC, PC/XT, AT, or Compatible  
Parallel cables to connect from IBM compatibles to the Modular Smart Switch  
require a 25-pin plug on both ends. All lines should be connected “straight-  
through” (that is, 1 to 1, 2 to 2, etc.).  
B.3 Cable to 36-Pin Amphenol Connector  
®
A standard IBM Centronics cable with a DB25 plug and a 36-pin Centronics  
plug is sufficient.  
64  
 

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