Rockwell Automation 1791DS-IBxxxx Guard I/O DeviceNet Safety Modules - Manual (Page 143)

Rockwell Automation Publication 1791DS-UM001J-EN-P - May 2013 143
Get Point Status from Modules by Using Explicit Messaging Appendix A
2. Use the InputStatus and OutputStatus bits to detect if one or more of the
I/O points on the module have a fault.
• If any input or output status bit goes to a value of 0 (0=bad, 1=good),
use an explicit message to determine which individual data points have
faulted. Use the InputState and OutputStatus bits to condition your
msg rung as follows.
• Note that the second rung can be used to read the status on mode
transition and once a fault is detected, continue reading until the fault is
corrected.
• Place these rungs in the standard task.
This figure shows the MSG instruction parameters for reading
Instance 819 from the 1791DS-IB4XOW4 module.
In this example, we created a UDT from the destination type.
• You can find the UDT called Assembly819_1791DS_IB4XOW4 in an
ACD file. This UDT is based on the Assembly819 for
1791DS_IB4XOW4 module.
• There are other assemblies in the EDS file that can be used, but this one is
the most inclusive.
• Make sure the Communication Path is set to the correct module.