Omron SYSMAC CS Series Operation Manual page 190

I/O Communication Characteristics
Example
Note
!Caution The default mapping of areas on to the PLC memory is the same default map-
Auto Addressing
The default mapping algorithm is illustrated in the figure below, with the fol-
lowing configuration:
• Slave device 1: One input/output module, one output modules.
• Slave device 2: One input module.
• Slave device 3: One output module.
• Slave device 4: Two input modules.
PLC CPU Unit
Output area
CIO 3200
Output area 1
CIO 3400
Output area 2
Input area
CIO 3300
Input area 1
CIO 3500
Input area 2
1. The end address of each Input/Output area in the PLC memory, depends
on the size of the allocated I/O data.
2. If more than 100 words of input or output have been configured for the
slave, overlap of memory areas will occur in the PLC, if default I/O map-
ping is used as shown above.
ping as used in the CS1/CJ1W-DRM21 Devicenet Master/Slave Unit. Care
should be taken to avoid data overlap, if such a Unit is part of the same PLC
CPU system as the CS1/CJ1W-PRM21 PROFIBUS Master Unit.
The CS1/CJ1W-PRM21 PROFIBUS Master Unit, will assemble the correct
PROFIBUS data messages from the storage order in the Input and Output
memory areas.
The default allocation of I/O modules, i.e. I/O modules are mapped in ascend-
ing order of slave addresses and module selection, uses the concept of Auto
Addressing of the CS1/CJ1W-PRM21 Master DTM. Auto Addressing will
(re)allocate I/O modules according to the algorithm explained above in each
area.
If a configuration has been selected, which is changed later - for example - by
adding an I/O module to one of the slaves, the Auto Addressing feature will
add that module to the default area, between the already selected modules of
that particular slave device.
PROFIBUS DP Master Unit
Output area
Output area 1
Output area 2
Input area
Input area 1
Input area 2
Section 6-5
Slave 1: Module 1
Slave 1: Module 2
Slave 3: Module 1
Slave 1: Module 1
Slave 2: Module 1
Slave 4: Module 1
Slave 4: Module 2
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