Input data file – Rockwell Automation 1769-OG16 Compact TTL Output Module User Manual
Page 14
14 Compact TTL Output Module
Publication 1769-IN078A-EN-P - May 2006
Input Data File
For each module, slot x, word 0 in the input data file contains the state of the
module’s output data file (output data echo). During normal operation, 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 configuration (if supported by the controller).
• Fault mode configuration (if supported by the controller).
The module implements inverted logic on the TTL outputs. An Output Data File bit
set to 1 directs a logic low output voltage on the corresponding output point. An
Output Data File bit cleared to 0 directs a logic high output voltage on the
corresponding output point.
Input Data File
Wo
rd
Bit Position
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
0
r
(1)
(1)
r = read.
r
r
r
r
r
r
r
r
r
r
r
r
r
r
r
IMPORTANT
The output module’s input data file 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.
It is important to use this input word if the controller adapter supports the
Program mode or Fault mode function, and if it is configured to use them.