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3 Memory Allocations
CJ-series EtherCAT Slave Units Operation Manual (W541)
3-2 CIO Area Allocations
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3-2-1 Overview of the Allocated CIO Area Words
3-2 CIO Area Allocations
This section describes CIO area allocations for the EtherCAT Slave Unit.
Various kinds of data are stored in the allocated CIO Area words, which are identified by the offset from
the beginning word (n) allocated to each Unit.
The beginning word n is calculated by the following equation:
Beginning word n = CIO 1500 + (25 × unit number)
Precautions for Correct Use
The reserved words are regularly refreshed with all zeroes.
3-2-1 Overview of the Allocated CIO Area Words
(Reserved)
Unit Status 1
Unit Status 2
Slave Status 1
Slave Status 2
(Reserved)
EtherCAT Slave Unit → CPU Unit
EtherCAT Slave Unit → CPU Unit
Offset
Bit
Data direction
n
n+1
n+2
n+3
n+4
n+5
n+6
n+7
n+8
n+9
n+10
n+11
n+12
n+13
n+14
n+15
n+16
n+17
n+18
n+19
n+20
n+21
n+22
n+23
n+24
15 8 7 0
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24