Glossary - Omron CS1W-SLK11-21 - 06-2004 Manual

address
advanced instruction
allocation
analog
Analog I/O Unit
AND
area
area prefix
ASCII
asynchronous execution
Auxiliary Area
auxiliary bit
backup
BASIC
basic instruction
BASIC Unit
baud rate
BCD
binary

Glossary

A number used to identify the location of data or programming instructions in
memory or to identify the location of a network or a unit in a network.
An instruction input with a function code that handles data processing opera-
tions within ladder diagrams, as opposed to a basic instruction, which makes
up the fundamental portion of a ladder diagram.
The process by which the PLC assigns certain bits or words in memory for var-
ious functions. This includes pairing I/O bits to I/O points on Units.
Something that represents or can process a continuous range of values as op-
posed to values that can be represented in distinct increments. Something that
represents or can process values represented in distinct increments is called
digital.
I/O Units that convert I/O between analog and digital values. An Analog Input
Unit converts an analog input to a digital value for processing by the PLC. An
Analog Output Unit converts a digital value to an analog output.
A logic operation whereby the result is true if and only if both premises are true.
In ladder-diagram programming the premises are usually ON/OFF states of
bits or the logical combination of such states called execution conditions.
See data area and memory area.
A one or two letter prefix used to identify a memory area in the PLC. All mem-
ory areas except the CIO Area require prefixes to identify addresses in them.
Short for American Standard Code for Information Interchange. ASCII is used
to code characters for output to printers and other external devices.
Execution of programs and servicing operations in which program execution
and servicing are not synchronized with each other.
A PLC data area allocated to flags and control bits.
A bit in the Auxiliary Area.
A copy made of existing data to ensure that the data will not be lost even if the
original data is corrupted or erased.
A common programming language. BASIC Units are programmed in BASIC.
A fundamental instruction used in a ladder diagram. See advanced instruction.
A CPU Bus Unit used to run programs in BASIC.
The data transmission speed between two devices in a system measured in
bits per second.
Short for binary-coded decimal.
A number system where all numbers are expressed in base 2, i.e., numbers
are written using only 0's and 1's. Each group of four binary bits is equivalent
to one hexadecimal digit. Binary data in memory is thus often expressed in
hexadecimal for convenience.
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