
4.LADDER LANGUAGE B-63983EN/02
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(9) Functional instruction operation result register
(R9000 to R9005) (See Fig. 4.2.1 (c).)
The results of executing functional instructions are set in this
register. The register is shared by all the functional instructions.
Therefore, if you do not reference the register immediately after
executing the target functional instruction, the operation data of
that instruction is erased as a subsequent functional instruction is
executed.
Also note that the operation data of this register cannot be
exchanged between sequence programs of different levels. For
example, when the subtraction instruction (SUBB) is executed in
a first level program and the result of its execution is set in the
register, a second level program cannot reference the set
operation data by reading the register in the R9000 range.
The operation data set in this register can be shared by sequence
programs of the same level and is maintained until immediately
before a functional instruction is executed that sets subsequent
operation data in the register. The operation data to be set in this
register differs for each functional instruction. The sequence
program can read this data but not write to this register.
76543210
R9000
R9001
R9002
R9003
R9004
R9005
Fig. 4.2.1 (c)
This register consists of six bytes, from R9000 to R9005. A single
block of data can be read from the register in bits or bytes at a time.
To read the data of the first bit of R9000, for example, specify RD
R9000.1.