Rockwell Automation 1770-KF2 Data Highway or Highway Plus Interface Module User Manual - Manual (Page 177)

Error Reporting
Chapter 7
7Ć22
15. Retransmits: Counts the number of duplicate frames received. A
duplicate frame is sent by a transmitter when it fails to receive an
ACK. If the reason it failed to receive an ACK was that the ACK
was lost, rather than because the original message was lost, the
duplicate is redundant and should be discarded. Any two successive
messages between polls that have the same sequence number fields
and the same command/reply bit are assumed to be duplicates.
16. Aborts: Counts the number of aborts received. The HDLC abort
signal is not used on the Data Highway but can be detected by the
SIO in certain circumstances. Some stations whose addresses match
the ringing pattern after a transmitter shutoff can be particularly
susceptible to this error (Stations 36, 76, and 176 for example).
These numbers will depend on highway configurations.
17. Transmitted Messages: A 16-bit counter that records the number of
messages successfully transmitted.
18. Not used.
19. Received Messages: A 16-bit counter that records the number of
messages successfully received.
20. Not used.
21. Commands Sent: A 16-bit counter that records the number of
command messages that were successfully generated as a result of a
start bit being set. Some of these messages may not be recorded as
being transmitted because they were either not successfully sent or
because they were sent to the same station that originated them.
22. Not used.
23. Messages Executed: A 16-bit counter that records the number of
command messages that were received to be executed from the
highway. This count does not depend on whether execution was
successful. For each message counted as received, a reply message
is sent.
24. Not used.