Western Telematic CAS-81 User Manual

WTI Part Number: 12365

Rev. C

CAS-81

8- Port Code Activated Switch

User's Guide

5 Sterling · Irvine · California 92618

[phone] · Toll Free: 1-800-854-7226

Fax: [phone] · http://www.wti.com

Table of Contents

1. In tro duc tion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1

2. Unit De scrip tion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

2.1. Front Panel In di ca tors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

2.2. Back Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

3. In stal la tion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

3.1. Set DIP Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

3.1.1. Data Rate (Baud) Se lec tion (Switches 1 through 3) . . . . . . . . . . . . . . 3-1

3.1.2. Ti me out Se lec tion (Switches 4 and 5) . . . . . . . . . . . . . . . . . . . . . . 3-1

3.1.3. Quiet Mode (Switch 6). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

3.1.4. Auto Con nect Se rial Port 1 (Switch 7). . . . . . . . . . . . . . . . . . . . . . 3-2

3.1.5. Broad cast Mode (Switch 8) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

3.1.6. Force CTS (Switch 9) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

3.1.7. Force DCD (Switch 10) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

3.2. Con nect Power Ca ble . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

3.3. Con nect De vices to Se rial Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

3.4. Con nect Con trol Port. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

3.5. RS422 Line Driver Op tion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

4. Op era tion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

4.1. Power Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

4.2. AS CII Char ac ters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

4.3. Com mand String . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

4.4. Com mand Re sponse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

4.5. Port Gat ing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

4.5.1. Open Port Gat ing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

4.5.2. Close Port Gat ing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

Ap pen di ces

A. De scrip tion of Sys tem In ter faces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Apx-1

A.1. Con trol Port (DB25 Fe male) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Apx-1

A.2. Se rial Ports 1 through 8 (DB9 Male) . . . . . . . . . . . . . . . . . . . . . . . . . . Apx-2

A.2.1. RS422 Line Driver Op tion . . . . . . . . . . . . . . . . . . . . . . . . . . . Apx-2

B. Speci fi ca tions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Apx-3

C. FCC No tice. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Apx-3

D. Cus tomer Serv ice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Apx-4

List of Figures

2.1. Front Panel Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

2.2. Back Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

A.1. Control Port / Serial Port Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Apx-1

A.2. RS422 Option Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Apx-2

2

1. Introduction

The CAS-81 Code Activated Switch brings the convenience of code-based RS232 switching to
sites with multiple terminals, printers, and peripherals. The CAS-81 enables a single RS232
Control Port to switch between 8 devices via an ASCII code sequence.

Code based switching lets you control the CAS-81 from your PC or mainframe. When a
modem is attached to the Control Port, the CAS-81 can also be managed from a remote
location. Devices can be connected or disconnected by sending commands from a remote PC
via modem.

The CAS-81 can operate at speeds up to 115,000 bps and passes data in "real-time" with no
delays. Binary and graphics files can be safely passed due to the unique 8 character switch
instruction, which considerably reduces the chances of false switching.

A broadcast mode makes it easy to mass-address a group of printers, display devices, or an
array of laboratory instruments by directing the data on the Control Port to all Serial Ports
simultaneously. The broadcast mode may be selected by code or permanently selected by the
Select Switch.

An Auto-connect feature allows the Control Port to automatically connect to Serial Port 1 each
time the unit is powered up, or after a timeout or disconnect. This provides a data path to a
critical device in case of a power failure, or convenient connection to commonly used
equipment.

Each Serial Port may be configured for a balanced RS422 long distance line driver by simply
removing the socketed RS232 driver chip and plugging in an optional RS422 module. When
the module is installed, an LED on the back panel indicates the port is RS422.

Applications

· Industrial Robotic and Numeric Control

· Remote Diagnostics

· Laboratory Equipment Polling

· Data Acquisition

· Network Management

Typographic Conventions

Throughout the manual, typefaces and characters have been used to denote the following:

^ (e.g. ^X) Indicates a key combination that is used to invoke a command.

For example, the text "^X" (Control X) indicates that the [Ctrl] key and

the [X] key should be pressed simultaneously.
COURIER FONT Indicates characters typed on the keyboard.

For example, ^VS or ^C#.

1-1

2. Unit Description

Figure 2.1: Front Panel Indicators

2.1. Front Panel Indicators

ON: Indicates power to the unit is ON.

À

RDY: Indicates unit is Ready to operate. A steady blink indicates that the CAS-81 is

Á

operating normally.

TXD: Indicates that data is being received at Control Port pin 2.

Â

RXD: Indicates that data is being transmitted out Control Port pin 3. Also indicates that

Ã

data is being received by pin 2 of a selected Serial Port.

RTS: Indicates that the "Request to Send" signal is present at Control Port pin 4.

Ä

CTS: Indicates that the "Clear to Send" signal is present at Control Port pin 5. Also

Å

indicates that the "Clear to Send" signal is present at pin 8 of a connected Serial Port.
Always high when all ports are disconnected.

DTR: Indicates that the "Data Terminal Ready" signal is present at Control Port pin 20.

Æ

DCD: Indicates that the "Data Carrier Detect" signal is present at Control Port pin 8.

Ç

Also indicates that the "Data Carrier Detect" signal is present at pin 1 of a connected
Serial Port. Always high when all ports are disconnected.

Serial Ports 1 - 8: Indicates that the corresponding numbered Serial Port is currently

È

connected.

2-1

CAS-81 Code Activated Switch, User's Guide Unit Description

Figure 2.2: Back Panel

2.2. Back Panel

Serial Ports 1 - 8: Eight RS232 DB9 male connectors configured as DTE. Accepts a

À

standard AT 9 pin to printer or modem cable, depending on the application. Refer to
Appendix A for more information on the Serial Port Interface.

Note that when the RS422 Line Driver Option has been installed, an LED indicator will
be present in the blank above the Serial Port. This LED indicates that the port is
configured for RS422 communication.

Control Port: RS232 DB25 female connector configured for DCE. Accepts a standard

Á

PC to Modem Cable.
The CAS-81 will respond to proper ASCII code strings received by the Control Port.

Once a port is selected, data will pass between the Control Port and the selected Serial
Port. Refer to Appendix A for more information on the Control Port interface.

Default Switch: An 8 position DIP switch that is used to select the Control Port Data

Â

Rate, No-data timeout period, and the Auto connect and broadcast features. This switch
is read upon power up.

AC Power: Standard AC power cord receptacle and ON/OFF switch.

Ã

2-2