Omron SYSMAC C1000H, Руководство по эксплуатации

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words (work bits), which can be used in programming to manipulate data and
control other bits. IR area work bits are reset when power is interrupted or
PC operation is stopped.
PC I/O words I/O bits Work words Work bits
C1000H 000 through 063 00000 through 06315 064 through 236 06400 through 23615
C2000H 000 though 127 00000 though 12715 128 through 236 12800 through 23615
The maximum number of available I/O bits is 16 (bits/word) times the number
of I/O words, i.e., 1,024 bits for the C1000H; 2,048 for the C2000H. I/O bits
are assigned to input or output points as described later in this section (see
Word Allocations ).
If a Unit brings inputs into the PC, the bit assigned to it is an input bit; if the
Unit sends an output from the PC, the bit is an output bit. To turn on an out-
put, the output bit assigned to it must be turned ON. When an input turns on,
the input bit assigned to it also turns ON. These facts can be used in the pro-
gram to access input status and control output status through I/O bits.
I/O bits that are not assigned to I/O points can be used as work bits.
Although normally not available as I/O words in the C1000H, IR 064 through
127 are used as I/O words by C1000H Remote I/O Systems to control I/O
points located on Remote I/O Units. Refer to the
Optical Remote I/O and
Wired Remote I/O System Manuals for details on Remote I/O Systems.
Input bits can be used to directly input external signals to the PC and can be
used in any order in programming. Each input bit can also be used in as
many instructions as required to achieve effective and proper control. They
cannot be used in instructions that control bit status, e.g., the OUTPUT, DIF-
FERENTIATE UP, and KEEP instructions.
Output bits are used to output program execution results and can be used in
any order in programming. Because outputs are refreshed only once during
each cycle (i.e., once each time the program is executed), any output bit can
be used in only one instruction that controls its status, including OUT,
KEEP(11), DIFU(13), DIFD(14) and SFT(10). If an output bit is used in more
than one such instruction, only the status determined by the last instruction
will actually be output from the PC.
See 5-12 Shift Register – SFT(10) for an example that uses an output bit in
two ‘bit-control’ instructions.
I/O words in the IR area are allocated to Units mounted on Racks by per-
forming the I/O Table Registration operation. This operation creates in mem-
ory a table called an I/O table that records what words and how many words
are allocated to the Unit in each slot and whether these words are input or
output words. The actual procedure for this operation is described in
Section
7 Program Input, Debugging, and Execution.
When the I/O Table Registration operation is performed, the system auto-
matically assigns word addresses to Units in the order in which they are
mounted left to right on the CPU Rack (or, in a Duplex System, on the CPU
I/O Rack) and then continuing left to right on any Expansion I/O Racks in the
order that the Expansion I/O Racks are connected. I/O words start from IR
000 for the first Unit and continue consecutively: IR 001, IR 002, etc.
Because different Units can require a different number of words, there are no
specific words associated with any particular slot. Rather, each Unit is as-
I/O Words
C1000H Remote I/O Words
Input Bit Usage
Output Bit Usage
Word Allocations
IR Area
Section 3-3