Omron 3G8F7-CRM21, User Manual

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Access to I/O Data Section 3-2
Precautions for Correct Use
When a Slave Unit occupies plural allocation areas, other Slave Units which
have the occupied node addresses cannot participate.
Example: When a Slave Unit with node address 0 exists in a network and it
occupies 2 words in the IN area and 4 words in OUT area, Word IN
Slave Units whose node addresses are 0 or 1, and Word OUT Slave
Units whose node addresses are 0, 1, 2 or 3 cannot participate.
Image of the above Precautions for Correct Use
Allocation area for IN Data of a Word IN Slave Unit
Allocation area for OUT Data of a Word OUT Slave Unit
Data allocation
•
8-Point Word IN Slave Unit
•
8-Point Word OUT Slave Unit
Word address Bit 15 Bit 0
+0 [IN data of Word MIX Slave Unit with node address 0]
+1
+2
IN
area
+3
+4
:
+62
+63
Word address Bit 15 Bit 0
+0
[OUT data of Word MIX Slave Unit with node address 0]
+1
+2
OUT
area
+3
+4
:
+62
+63
IN area
1 2 3 4 5 6 7 0
Unused
OUT area
1 2 3 4 5 6 7 0
Unused