Rockwell Automation 2706-M1 MESSAGEVIEW 421 HARDWARE MANUAL - Manual (Page 124)

Glossary G–4
Publication 2706-816 – November 1996
I –
Inverse Video – A Message or part of a message that is emphasized
by having its colors reversed in the MessageView terminal display.
ISA – Acronym for Instrumentation Society of America.
MessageBuilder software includes a set of standard ISA bitmap
Graphic symbols that can be embedded in a message.
J –
Jog Feature – One aspect of the Auto Clear attribute. When Auto
Clear is disabled for a Message that has embedded Function Keys,
jog feature is activated. A message with jog feature enabled remains
active until the terminal is reset or the display is cleared. A message
with jog feature disabled is terminated after one of its function keys
is pressed.
K –
Keypad – A set of keys on the MessageView terminal that the
terminal operator uses to input data, acknowledge messages and
access the Front Panel Editor. See also Numeric Keypad and
Function Keys.
L –
LED – Acronym for Light Emitting Diode. Each MessageView
terminal has two terminal status LEDs (Comm and Fault) on the
back. Their state can be checked in the Front Panel Editor. In
addition, a MessageView 421F terminal has a red LED beside each
of the 16 Function Keys. These LEDs may or may not reflect the
condition of the function key, depending on how they are set up in
the Application.
Logic Controller – A device used to replace relay logic used for
sequencing, timing, and counting. Instead of physical wiring devices
such as relays, push buttons and limit switches, a logic controller
tests the state of inputs and sets outputs according to stored
programs. A MessageView terminal with an Remote I/O port
receives commands from a logic controller to run an application.
Also called programmable controller. See also SLC; PLC.