Omron SYSMAC C200HW-PCS01-EV1, Руководство по эксплуатации

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Glossary
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comprise the System. In OMRON terminology, system configuration is used to
describe the arrangement and connection of the Units comprising a Control Sys-
tem that includes one or more PCs.
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.
system setup Parameters set to control the operation of the CVSS, CPU Bus Units, etc.
target node See remote node.
TCP Transmission Control Protocol: Performs communications after establishing a
connection (i.e., a virtual circuit) with the target node to provide a highly reliable
communications method.
terminator 1) 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. 2) Unit in a Link System desig-
nated as the last Unit on the communications line. 3) A device attached to the
end of a network communications line to specify the end of the network.
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 execution
conditions.
transceiver A physical interface to a network that converts signals.
transfer The process of moving data from one location to another within the PC, or
between the PC 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.
UDP User Datagram Protocol: Performs datagram communications. Data resends,
priority control, flow control, and other measures to ensure communications reli-
ability are not performed for UDP communications, i.e., there is no way of guar-
anteeing normal communications without programming special measures to do
so into the user’s application program.
UM area The memory area used to hold the active program, i.e., the program that is being
currently executed.
Unit In OMRON PC terminology, the word Unit is capitalized to indicate any product
sold for a PC 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 collective sense
as a Unit. Context generally makes any limitations of this word clear.
unit address A number used to control network communications in FINS protocol. Unit
addresses are computed for Units in various ways, e.g., 10 hex is added to the
unit number to determine the unit address for a CPU Bus Unit.
unit number A number assigned to some Link Units, Special I/O Units, and CPU Bus Units to
facilitate identification when assigning words or other operating parameters.