Rockwell Automation 1794-ASB/E Remote I/O Adapter Module User Manual User Manual
Page 43
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3–9
Communicating with FLEX I/O Modules
Publication 1794ĆUM009D-EN-P - April 2004
Input modules and Output modules in pairs, or analog modules.
Eight terminal bases per adapter (maximum)
Adapter
20128
Each module represents 1/2 of an I/Ogroup
Group 0
Group 1
Group 2
Group 3
Input
Output
Input
Output
Output
Input
Analog
Analog
16Ćpoint Compact Addressing
2 modules represent 1 I/Ogroup
8 modules = 1/2 I/Orack
00
07
10
17
00
07
10
17
0
1
2
3
4
5
6
7
I/O Group
Input Image Table
Output Image Table
M0
M1
M2
M3
M4
M5
M6
M7
IL = Input Low Byte
IH = Input High Byte
OL = Output Low Byte
OH = Output High Byte
MCB = Module Control Byte (output data)
MSB = Module Status Byte (input data)
ASB/E
IH
IL
IH
IL
OH
OL
IB16
IB16
IB16
OH
OL
M0ĆIL
M2ĆIL
M4ĆMSB
M7ĆIL
M0ĆIH
M2ĆIH
M5ĆMSB
M7ĆIH
M1ĆOL
M3ĆOL
M4ĆMCB
M6ĆOL
M1ĆOH
M3ĆOH
M5ĆMCB
M6ĆOH
MCB
MSB
OB16
MCB
MSB
IE8
IE8
OH
OL
IH
IL
OB16
OB16
Compact 16Ćpoint Addressing Example
I/OGroup 0
I/OGroup 1
I/OGroup 2
I/OGroup 3
- 8 modules = 1/2 logical rack = 4 I/O groups
2 module positions = an I/O group
Legal Module Placement in 16Ćpt Compact Addressing
A 16Ćpoint input module and a 16Ćpoint output module
(or an empty slot) in an I/Ogroup.
Note: Shaded areas represent unavailable data
I/O groups 4-7 are available for another adapter.
Note: When using block transfer modules in 16Ćpt compact addressing, address module positions
M0, M2, M4 and M6 as module 0" in a block transfer instruction block; address module positions
M1, M3, M5 and M7 as module 1" in a block transfer instruction block.
A 16Ćpt output module and a 16Ćpt input module
(or an empty slot) in an I/Ogroup.
A block transfer module with another block transfer module
(or an empty slot) in an I/Ogroup.
An empty slot with any module, or another empty
slot in an I/Ogroup.