Safety Considerations Guide for Trident v2 Systems - TUV ...

70 Appendix A Triconex Peer-to-Peer Communication
This example packs 32 BOOL values into a DWORD and sends the DWORD and a diagnostic
variable to a receiving node as fast as possible by setting the sendflag parameter to 1 all the time.
The diagnostic variable is incremented every time a new SEND is initiated. The receiving node
checks the diagnostic variable to verify that it has changed from the previous value received.
The receiving node also determines whether it has received at least one data transfer within the
process-tolerance time. If not, the application takes appropriate action, such as using the last
data received or using default data to make safety-critical decisions.
This example uses the following project elements:
• PEER_EX4_SEND_FBD (for sending Node #1)
• PEER_EX4_RCV_FBD (for receiving Node #3)
Safety Considerations Guide for Trident v2 Systems