Rockwell Automation 2706-F11J_F11JC_F21J_F21JC DL50 INSTALLATION MANUAL - Manual (Page 51)

A–B
5
Chapter
5–1
Serial Communications
This chapter describes how to communicate with the DL50 using a simple
ASCII string format. The DL50 supports both simplex and duplex
communications protocols. Each will be addressed in this chapter.
Simplex Communications- In this protocol, the DL50 does not provide any
responses to the master device. The DL50 receives message packets from the
master device and uses this information to display text. Use this protocol
when the commands are sent from Allen-Bradley Dataliner DL20 and DL40
message displays.
Duplex Communications- In this protocol, the DL50 provides a response to
each command it receives. The response includes data checking bytes
(Checksum) and a handshake byte (ACK/NAK). The DL50 receives message
packets from the master device, transmits data checksum/handshake bytes
back to the master, and uses the message data to display text.
The Duplex Protocol section starts on page 5-8.
The DL50 can communicate with a wide range of host devices using either
the Simplex or Duplex protocols. These protocols are selected through
dipswitch configuration of the DL50 display. Table 5.A lists typical
Allen-Bradley products that can drive DL50 displays, together with the
protocol(s) they can support.
Table 5.A
Host Device Compatibility with Simplex and Duplex Protocol Formats
Product Family Host Device Host COM Port Simplex Duplex
Dataliner Displays Dataliner DL40 Message Displays
Dataliner DL20 Message Displays RS-485
RS-232 / RS-422 YES
YES NO
NO
MessageView
Displays MessageView 2706-M1D1, -M1N1, -M1F1 RS-232 YES NO
PLC 5 PLC 5 Family Programmable Controllers
BASIC Module (1771-DB)
ASCII I/O Module (1771-DA)
Flexible Interface Module (2760-RB) Channel #0 RS-232
RS-232/RS-485
RS-232
RS–232/RS-422 YES
YES
YES
YES YES
YES
YES
YES
SLC500 SLC 5/03 Small Logic Controller
SLC 5/04 Small Logic Controller
BASIC Module (1746-BAS) Channel #0 RS-232
Channel #0 RS-232
RS-232/RS-485 YES
YES
YES YES
YES
YES
Chapter Objectives
Protocols
Host Device Compatibility