Omron CJ1W-C113 - REV 02-2008, Operation Manual

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Reading Data with IORD Section 5-5
Program example Work bit R1 is used to start writing. When debugging, it is a good idea to cre-
ate a ladder program that refers to the ER Flag and Error Flag (word n+8,
bit12).
5-5 Reading Data with IORD
5-5-1 Outline
This section outlines how to read positioning sequences from a PCU. Using
IORD, 128 words of data in consecutive addresses can be read at one time.
Refer to
5-4 Writing Data with IOWR for an outline.
5-5-2 READ DATA Procedure
Refer to 5-5-3 IORD: INTELLIGENT I/O READ or the CS/CJ-series Program-
mable Controllers Instruction Reference Manual (W340) for details on how to
set the operands for IORD.
1,2,3... 1. Set IORD.
C: Beginning address of the PCU data area.
W: Unit number of the PCU reading the data and the total number of
words to be read.
D: Beginning word address of the area in the CPU Unit where the read
data will be stored.
2. Read the data.
Execute IORD.
5-5-3 IORD: INTELLIGENT I/O READ
An explanation of how to use the IORD instruction is given here.
DIFU R1
IOWR
#112C
D00500
#00040002
R3
R2
R1
R2
R3
=
Set the beginning address (transfer
destination) of the speed data to be
transferred to the PCU to 112C (Hex).
Set the beginning word (transfer
source) of the area in the CPU Unit
where the speed data is set to D00500.
Set the unit number of the transfer des-
tination to 2 (Hex) and the number of
transfer words to 4 (Hex).
If transfer is completed successful-
ly, the Equals Flag turns ON.
Work bit
Work bit
Write switch
Work bit
Work bit
IORD
C
W
D
@IORD
C
W
D