Rockwell Automation 2706-M1 MESSAGEVIEW 421 HARDWARE MANUAL - Manual (Page 126)

Glossary G–6
Publication 2706-816 – November 1996
P –
Parameter – A characteristic of a device or system that is defined
as part of its set-up. For instance, a MessageView terminal’s Remote
I/O port must have the controller type, its baud rate, and other
parameters specified so it can communicate with the specific type of
Logic Controller the system will use. Communications parameters
may be viewed using Front Panel Editor commands.
PLC – Acronym for Programmable Logic Controller, an
Allen-Bradley trademarked device.
Port – The part of a Device through which it communicates with
other devices. Before two devices can communicate, they must have
a hardware connector (cable) joining their ports and both ports must
have the correct software communication Parameters set. A
MessageView terminal has an RS-232 port and may also have a
Remote I/O port.
Power-On Self Tests – The tests run by the terminal when it is
powered up. The terminal operator can run any of these tests
individually using a Front Panel Editor command. Also referred to
as POST.
Preset Value – A value that is loaded into a PLC or SLC controller
data table when an Application starts up in a MessageView
terminal.
Programmable Controller – See Logic Controller.
R –
Real Time Clock – The MessageView terminal has its own
battery-operated clock, referred to by this name or RTC. It provides
values for time or date variables in displayed messages. The
terminal’s clock may be set using the Front Panel Editor or a
command from MessageBuilder software.