Rockwell Automation 2706-MB1 MESSAGEVIEW 421 SOFTWARE MANUAL - Manual (Page 90)

Chapter
5
Publication 2706-817
Communications Overview
This chapter covers the following topics:
•
MessageView 421 terminal ports
•
RS-232 Port communication
•
ASCII Triggering commands
•
Remote I/O communication
•
Discrete I/O
•
Block transfer.
Each Message View 421 terminal has a standard RS-232 port on the
Main Logic Board. It may also include an optional Remote I/O
(RIO) Communications daughterboard card.
The MessageView terminal’s two available ports are used as follows:
•
The Remote I/O Port (optional) connects to a logic controller on a
Remote I/O network.
•
The RS-232 Port connects to:
– the RS-232 port of a personal computer
– other devices set up in the application to be used when the
terminal is in Run Mode, which are listed on Page 5–3.
Remote I/O Port
Certain MessageView terminals have a Remote I/O Port installed
(Catalog Nos. 2706-M1D1, -M1N1 and -M1F1). The RIO port is
used for the sole purpose of communicating with:
•
a logic controller, which runs the operation
The Remote I/O port of a MessageView terminal, when connected to
a logic controller, is used to transmit and receive data utilizing
discrete I/O and block transfer modes.
Each MessageView terminal is configured to match the device type
and communication parameters of the Logic Controller in its Remote
I/O system. The configuration is set up when the application is
created, so a terminal may be used in a variety of systems according
to the application downloaded into it. This will be discussed starting
on Page 5–12.
MessageView 421 Terminal
Ports