Omron SYSMAC CS Series Operation Manual page 191

I/O Communication Characteristics
!Caution When an I/O module is added to or deleted from a configuration at a later
Note
Example
Re-allocating I/O Modules
1,2,3...
170
point in time, Auto Addressing will cause a change in the addresses of subse-
quent I/O modules in an Input/Output area. This will cause I/O data of (a part
of the) slave devices to be re-mapped to different locations in the PLC mem-
ory. In order to avoid unexpected results, the PLC user program may have to
be adapted as well.
1. Auto Addressing will not change the allocation of I/O modules to a certain
area, i.e. a module allocated to Input/Output area 2, will not be re-allocated
to area 1, if Auto Addressing is enabled.
2. Auto Addressing will not change the start address of the areas.
3. Auto Addressing is by default enabled, when starting a new project. It is
however, disabled for existing projects to avoid unwanted re-mapping.
The figure below shows an example of the effects of Auto Addressing on
(re)allocation of I/O modules. In the original I/O configuration on the left, the
first slave - an OMRON CJ1W-PRT21 - consisted of two I/O modules. In new
configuration one I/O module was inserted, and subsequent modules were re-
allocated in the process.
Initial I/O Configuration
Note The start address of Output area 1 in the example remains the same, after
adding an I/O module.
After setting up the initial I/O configuration, the I/O modules can be re-
mapped to the second Input/Output area. This can be accomplished by using
drag & drop to move the I/O modules. To accomplish this, perform the follow-
ing sequence.
1. Open the CS1/CJ1W-PRM21 Master DTM - Configuration User Interface.
2. Select the Slave Area tab. The window shows two sub tabs: One for Out-
put Allocation and one for Input Allocation. The following points apply to
each of these tabs.
3. After setting up the initial I/O configuration, all I/O modules will be shown
in the overall list in the upper half of the Slave Area tab. This is a pick list
Section 6-5
One I/O module of two output
words was inserted, and re-allocated
subsequent I/O modules.