Fixed Allocations; Allocated Words - Omron CJ1W-DRM21 Operation Manual

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Fixed Allocations

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Allocated Words

If fixed allocation is used, allocated words are in the following I/O (CIO) area in the memory used for CJ-
series Unit. You
*_Sw2SlavFixAloc1Cmd to *_Sw2SlavFixAloc3Cmd (Slave Fixed Allocation Setting 1 to 3 Switch) to
select the allocation area.
Each area is comprised of an OUT area that is used to write data to the master IN area and an IN area
that is used for inputs from the master OUT area in remote I/O communications.
To access the following areas from the user program, user-defined variables that specify the AT specifi-
cation of these areas need to be defined.
Area
Fixed allocation area 1 CIO 3370
Fixed allocation area 2 CIO 3570
Fixed allocation area 3 CIO 3770
You can include a maximum of 3 CJ-series DeviceNet Units as slaves in a single NJ-series CPU Unit
because the three allocation areas above are set individually for fixed allocations. The default setting is
fixed allocation area 1.
Allocation Procedures
Step 1: Set the CPU Unit to PROGRAM Mode.
Step 2: Stop Slave Communications
If the Unit already functions as a Slave Unit, change *_Sw2SlavDsblCmd (Slave Stop Switch) to
TRUE to stop slave communications. This step is not necessary if slave communications are
stopped.
Step 3: Select a Fixed Allocation Area
Change *_Sw2SlavFixAloc1Cmd to *_ Sw2SlavFixAloc3Cmd (Slave Fixed Allocation Setting 1 to 3
Switch) to TRUE to select a fixed allocations area between 1 and 3.
One word is allocated for the output (OUT) area from the Slave Unit to the CPU Unit and another
word is allocated for the input (IN) area from the CPU Unit to the Slave Unit in the memory used for
CJ-series Unit, as shown below.
CJ-series DeviceNet Units Operation Manual for NJ-series CPU Unit(W497)
can select words
OUT area
(master to slave) (slave to master)
CIO 3270
CIO 3470
CIO 3670
5 Remote I/O Slave Communications
from one of three fixed
IN area
Change *_Sw2SlavFixAloc1Cmd
(Slave Fixed Allocation Setting 1
Switch) to TRUE.
Change *_Sw2SlavFixAloc2Cmd
(Slave Fixed Allocation Setting 2
Switch) to TRUE.
Change *_Sw2SlavFixAloc3Cmd
(Slave Fixed Allocation Setting 3
Switch) to TRUE.
allocations areas.
Selection method
Use
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