Omron SYSMAC C200H, Руководство по эксплуатации

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Glossary
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PC controlling the Master and a PC connected to the Remote I/O System
through an I/O Link Unit or an I/O Link Rack.
I/O Link Unit A Unit used with certain PCs to create an I/O Link in an Optical Remote I/O
System.
I/O point The place at which an input signal enters the PC System, or at which an out-
put signal leaves the PC System. In physical terms, I/O points correspond to
terminals or connector pins on a Unit; in terms of programming, an I/O points
correspond to I/O bits in the IR area.
I/O response time The time required for an output signal to be sent from the PC in response to
an input signal received from an external device.
I/O table A table created within the memory of the PC that lists the IR area words allo-
cated to each Unit in the PC System. The I/O table can be created by, or mo-
dified from, a Programming Device.
I/O Unit The most basic type of Unit mounted to a backplane to create a Rack. I/O
Units include Input Units and Output Units, each of which is available in a
range of specifications. I/O Units do not include Special I/O Units, Link Units,
etc.
I/O word A word in the IR area that is allocated to a Unit in the PC System.
IR area A data area whose principal function is to hold the status of inputs coming
into the system and that of outputs that are to be set out of the system. Bits
and words in the IR that are used this way are called I/O bits and I/O words.
The remaining bits in the IR area are work bits.
JIS Acronym for Japanese Industrial Standards.
jump A type of programming where execution moves directly from one point in a
program to another, without sequentially executing any instructions inbe-
tween. Jumps are usually conditional on an execution condition.
jump number A definer used with a jump that defines the points from and to which a jump
is to be made.
ladder diagram (program) A form of program arising out of relay-based control systems that uses cir-
cuit-type diagrams to represent the logic flow of programming instructions.
The appearance of the program is similar to a ladder, and thus the name.
ladder diagram symbol A symbol used in a ladder-diagram program.
ladder instruction An instruction that represents the ‘rung’ portion of a ladder-diagram program.
The other instructions in a ladder diagram fall along the right side of the dia-
gram and are called terminal instructions.
Ladder Support Software A software package that provides most of the functions of the Factory Intelli-
gent Terminal on an IBM AT, IBM XT, or compatible computer.
LAN An acronym for local area network.
leftmost (bit/word) The highest numbered bits of a group of bits, generally of an entire word, or
the highest numbered words of a group of words. These bits/words are often
called most-significant bits/words.