Western Telematic CAS-81 Benutzerhandbuch

The Serial Ports are 9 pin male, wired in a DTE configuration similar to that of an A computer.
Figure A.1 and the table below describe the Serial Port interface.

1

DCD

Input

-

To Control Port Pin 8

2

RXD

Input

-

To Control Port Pin 3

3

TXD

Output

Low

Follows Control Port Pin 2

4

DTR

Output

Low

Follows Control Port Pin 20

5

GND

Signal Ground

6

Open

7

RTS

Output

Low

Follows Control Port Pin 4

8

CTS

Input

-

To Control Port Pin 5

9

Open

Each Serial Port may be configured with an RS422 balanced line driver.  These long distance
line drivers can extend high speed transmission distance to 4,000 feet using 2 twisted pair
wiring.  Only the TXD and RXD signals are transmitted.  The DCD and CTS signals are set to
high.  Figure A.2 below describes the RS422 Serial Port interface.

Note: Handshake signals are not passed.  All other pins are open.