Allen-Bradley Compact I/O 1769-ADN DeviceNet, Руководство пользователя

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Publication 1769-UM001B-EN-P - October 2002
How Communication Takes Place and I/O Image Table Mapping 2-7
1769-OA8 100 to 240V AC
Solid State Output Module
(8 Point)
Output Data
For each 1769-OA8 module, output data word 0 contains the control
program’s directed state of the discrete output points. Bits 8 to 15 are
not used.
Input Data
For each 1769-OA8 module, input data word 0 contains the state of
the module’s output data (output data echo) word 0. During normal
operation (controller in Run), these input bits represent the logic state
that the outputs are directed to by the control program. They are also
dependent upon the:
•
Program Mode (Hold Last or User-Defined Safe State)
configuration
•
Fault Mode (Hold Last or User-Defined Safe State) configuration
For the 1769-OA8, input data word 0 bits 8 to 15 are not used.
Wo
rd
Bit Position
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
0 0 0 0 0 0 0 0 0 w w w w w w w w
w = write
Wo
rd
Bit Position
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
0 0 0 0 0 0 0 0 0 r r r r r r r r
r = read
IMPORTANT
The output module’s input data reflects the output
data echo of the module, not necessarily the
electrical state of the output terminals. It does not
reflect shorted or open outputs.
Allen-Bradley