Rockwell Automation 1766-Lxxxx MicroLogix 1400 Programmable Controllers User Manual - Manual (Page 396)

356 Rockwell Automation Publication 1766-UM001H-EN-P - May 2014
Glossary
read
To acquire data from a storage place. For example, the processor READs
information from the input data file to solve the ladder program.
relay
An electrically operated device that mechanically switches electrical circuits.
relay logic
A representation of the program or other logic in a form normally used for relays.
restore
To download (transfer) a program from a personal computer to a controller.
reserved bit
A status file location that the user should not read or write to.
retentive data
Information associated with data files (timers, counters, inputs, and outputs) in a
program that is preserved through power cycles.
RS-232
An EIA standard that specifies electrical, mechanical, and functional
characteristics for serial binary communication circuits. A single-ended serial
communication interface.
run mode
This is an executing mode during which the controller scans or executes the
ladder program, monitors input devices, energizes output devices, and acts on
enabled I/O forces.
rung
Ladder logic is comprised of a set of rungs. A rung contains input and output
instructions. During Run mode, the inputs on a rung are evaluated to be true or
false. If a path of true logic exists, the outputs are made true. If all paths are false,
the outputs are made false.
save
To upload (transfer) a program stored in memory from a controller to a personal
computer; OR to save a program to a computer hard disk.