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

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Glossary
syntax error An error in the way in which a program is written. Syntax errors can include
‘spelling’ mistakes (i.e., a function code that does not exist), mistakes in spec-
ifying operands within acceptable parameters (e.g., specifying read-only bits
as a destination), and mistakes in actual application of instructions (e.g., a call
to a subroutine that does not exist).
SYSMAC LINK System A communications system used to create data links and enable network com-
munications between PLCs.
SYSMAC NET Link System An optical LAN formed from PLCs connected through SYSMAC NET Link
Units. A SYSMAC NET Link System also normally contains nodes interfacing
computers and other peripheral devices. PLCs in the SYSMAC NET Link Sys-
tem can pass data back and forth, receive commands from any interfaced
computer, and share any interfaced peripheral device.
SYSMAC NET Link Unit The Unit used to connect PLCs to a SYSMAC NET Link System.
system configuration The arrangement in which Units in a System are connected. This term refers
to the conceptual arrangement and wiring together of all the devices needed
to comprise the System. In OMRON terminology, system configuration is used
to describe the arrangement and connection of the Units comprising a Control
System that includes one or more PLCs.
system error An error generated by the system, as opposed to one resulting from execution
of an instruction designed to generate an error.
system error message An error message generated by the system, as opposed to one resulting from
execution of an instruction designed to generate a message.
terminator The code comprising an asterisk and a carriage return (* CR) which indicates
the end of a block of data in communications between devices. Frames within
a multi-frame block are separated by delimiters. Also a Unit in a Link System
designated as the last Unit on the communications line.
timer A location in memory accessed through a TC bit and used to time down from
the timer’s set value. Timers are turned ON and reset according to their exe-
cution conditions.
TR Area A data area used to store execution conditions so that they can be reloaded
later for use with other instructions.
TR bit A bit in the TR Area.
transfer The process of moving data from one location to another within the PLC, or be-
tween the PLC and external devices. When data is transferred, generally a
copy of the data is sent to the destination, i.e., the content of the source of the
transfer is not changed.
transmission distance The distance that a signal can be transmitted.
UM area The memory area used to hold the active program, i.e., the program that is be-
ing currently executed.
Unit In OMRON PLC terminology, the word Unit is capitalized to indicate any prod-
uct sold for a PLC System. Though most of the names of these products end
with the word Unit, not all do, e.g., a Remote Terminal is referred to in a collec-
tive sense as a Unit. Context generally makes any limitations of this word clear.