Omron CS1W-SLK11-21 - 06-2004, Руководство пользователя

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Glossary
binary-coded decimal A system used to represent numbers so that every four binary bits is numeri-
cally equivalent to one decimal digit.
bit The smallest piece of information that can be represented on a computer. A bit
has the value of either zero or one, corresponding to the electrical signals ON
and OFF. A bit represents one binary digit. Some bits at particular addresses
are allocated to special purposes, such as holding the status of input from ex-
ternal devices, while other bits are available for general use in programming.
bit address The location in memory where a bit of data is stored. A bit address specifies
the data area and word that is being addressed as well as the number of the
bit within the word.
Branching Link Adapter A Link Adapter used to branch connections to Units in a Link System used ei-
ther to prevent the entire System from shutting down for an interruption at only
one point in the System, or to enable connecting more than two Units in one
System when each Unit provides only one connector.
buffer A temporary storage space for data in a computerized device.
building-block PLC A PLC that is constructed from individual components, or “building blocks.”
With building-block PLCs, there is no one Unit that is independently identifiable
as a PLC. The PLC is rather a functional assembly of Units.
bus A communications path used to pass data between any of the Units connected
to it.
bus link A data link that passed data between two Units across a bus.
byte A unit of data equivalent to 8 bits, i.e., half a word.
central processing unit A device that is capable of storing programs and data, and executing the in-
structions contained in the programs. In a PLC System, the central processing
unit executes the program, processes I/O signals, communicates with external
devices, etc.
channel See word .
character code A numeric (usually binary) code used to represent an alphanumeric character.
checksum A sum transmitted with a data pack in communications. The checksum can be
recalculated from the received data to confirm that the data in the transmission
has not been corrupted.
CIM Computer integrated manufacturing; a process where one or more computers
are used to control and integrate manufacturing processes.
CIO Area A memory area used to control I/O and to store and manipulate data. CIO Area
addresses do not require prefixes.
combined Link System A control system that includes more than one of the following systems: Remote
I/O System, SYSMAC Link System, Host Link System, or SYSMAC NET Link
System.
common (link) parameter table
A table of settings in a SYSMAC LINK System that specifies what words are to
be used in the data links for all PLCs in the SYSMAC LINK System. See
re-
fresh parameter table .