Omron SYSMAC C200H, Руководство по эксплуатации

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OR NOT between just IR 00003 and the result of an AND between IR 00002
and the first OR. What we need is a way to do the OR (NOT)’s independently
and then combine the results.
To do this, we can use the LOAD or LOAD NOT instruction in the middle of
an instruction line. When LOAD or LOAD NOT is executed in this way, the
current execution condition is saved in a special buffer and the logic process
is restarted. To combine the results of the current execution condition with
that of a previous “unused” execution condition, an AND LOAD or an OR
LOAD instruction is used. Here “LOAD” refers to loading the last unused ex-
ecution condition. An unused execution condition is produced by using the
LOAD or LOAD NOT instruction for any but the first condition on an instruc-
tion line.
Analyzing the above ladder diagram in terms of mnemonic instructions, the
condition for IR 00000 is a LOAD instruction and the condition below it is an
OR instruction between the status of IR 00000 and that of IR 00001. The
condition at IR 00002 is another LOAD instruction and the condition below is
an OR NOT instruction, i.e., an OR between the status of IR 00002 and the
inverse of the status of IR 00003. To arrive at the execution condition for the
instruction at the right, the logical AND of the execution conditions resulting
from these two blocks will have to be taken. AND LOAD does this. The mne-
monic code for the ladder diagram is shown below. The AND LOAD instruc-
tion requires no operands of its own, because it operates on previously deter-
mined execution conditions. Here too, dashes are used to indicate that no
operands needs designated or input.
The following diagram requires an OR LOAD instruction between the top log-
ic block and the bottom logic block. An ON execution condition will be pro-
duced for the instruction at the right either when IR 00000 is ON and IR
00001 is OFF, or when IR 00002 and IR 00003 are both ON. The operation
of the OR LOAD instruction and its mnemonic code is exactly the same as
that for an AND LOAD instruction, except that the current execution condition
is ORed with the last unused execution condition.
Instruction
00000 00001
00002 00003
Address Instruction Operands
00000 LD 00000
00001 AND NOT 00001
00002 LD 00002
00003 AND 00003
00004 OR LD ---
Naturally, some diagrams will require both AND LOAD and OR LOAD instruc-
tions.
To code diagrams with logic block instructions in series, the diagram must be
divided into logic blocks. Each block is coded using a LOAD instruction to
code the first condition, and then AND LOAD or OR LOAD is used to logically
combine the blocks. With both AND LOAD and OR LOAD there are two ways
to achieve this. One is to code the logic block instruction after the first two
blocks and then after each additional block. The other is to code all of the
OR LOAD
Logic Block Instructions in
Series
Basic Ladder Diagrams
Section 4-3