Rockwell Automation Publication 1734-UM013J-EN-P - July 2014 157
Get I/O Diagnostic Status from Modules in Logix Systems Appendix B
Class, Instance, and Attribute 
Data for I/O Modules
Use the information in the following tables to configure your message 
instruction.
Table 12 - Digital Safety Input Module (1734-IB8S)
Service Type Function Command (hex) Response (hex)
Service 
Code
Class ID Instance ID Attribute ID Data 
Size
Get Attribute 
Single
Reads the cause for the safety digital input 
fault specified by the Instance ID (1…8).
0E  3D  01…08 6E  - 0: No error 
01: Configuration invalid
02: External test signal error
03:Internal input error
04: Discrepancy error
05: Error in the other dual channel input
Table 13 - Digital Safety Input Module Test Outputs (1734-IB8S)
Service Type Function Command (hex) Response (hex)
Service 
Code
Class ID Instance ID Attribute ID Data Size
Get Attribute 
Single
Reads the cause of the test output fault 
specified by the Instance ID (1…4).
0E  09  01…04 76  - 0 = No error
01: Configuration invalid
02: Overload detected
03: Cross circuit detected
05: Output ON error
06: Undercurrent detected for muting lamp
Set Attribute 
Single
Configures the test output to turn off or hold 
its last state after a communication error for 
an output specified by the Instance ID.
10 09 01…04 05  1 byte 
00: Clear
01: Hold
-
Table 14 - Digital Safety Output Module (1734-OB8S)
Service Type Function Command (hex) Response (hex)
Service 
Code
Class ID Instance ID Attribute ID Data Size
Get Attribute 
Single
Reads the cause for the safety digital output 
fault specified by the Instance ID (1…8).
0E  3B  01…08  6E  - 0: No error
01: Configuration invalid
02: Over current detected
03: Short circuit detected
04: Output ON error
05: Error in the other dual channel output
06: N/A
07: N/A
08: Dual channel violation
09: Short circuit detected at safety output