Serial Port Connectors - Allen-Bradley A-B QUALITY DL20 Series User Manual

Chapter Objectives

Serial Port Connectors

The Serial Port
This chapter describes the serial port of the DL20. You can use the serial
port to send or receive data using RS-232 or RS-422 standards. It describes:
Serial port connectors
How to connect devices to the serial port
Serial port data formats
Addressable master feature
Slave displays
Figure 6.1 shows the serial port connectors of the DL20. All serial port
connectors are optically isolated from the main circuitry in the DL20.
Figure 6.1
Serial Port Connectors
SERIAL COMM PORT
RS
RS
422 422
-
+
4 5
Terminal Function
4, 5 Send or Receive RS-422 Data
RS-232 Data Output
6
7 RS-232 Data Input
8 RS-232 Common
9 +12 VDC asserts certain RS-232 Handshake Lines,
on terminals or printers. Do not use as a power source.
Cable shields should terminate at terminal 8 (Common).
Terminals 4 and 5 send and receive RS-422 data.
Terminal 7 is the RS-232 input and terminal 6 is the output.
Terminal 8 is RS-232 common; all cable shields are terminated here.
Terminal 9 is a +12 VDC output for asserting handshake lines on some
printers or terminals. Do not use this output as a power source. There is a
plastic cover over terminal 9 to prevent inadvertent connections.
6
Chapter
A–B
RS RS +12
See Chapter 9 for
232 232 VDC
wiring connections.
OUT IN GND OUT
6 7 8 9
6–1