Rockwell Automation 1770, D17706.5.16 Ref Mnl DF1 Protocol Command - Manual (Page 161)

9–23 Diagnostic Counters
Publication 1770Ć6.5.16 - October 1996
1775ĆS5,ĆSR5 DH+ Diagnostic Counters
This counter byte Counts the number of
0, 1
Messages sent successfully.
2, 3 Message received successfully (not counting duplicate messages).
4 Undeliverable messages (message was NAKed or retries were used
up).
5 ACK timeouts; sent a packet that did not get acknowledged or wait
acknowledged.
6 Received NAKs.
7 Message retries as a result of CRC error, illegal length, DST not
equal to this node, SRC not equal to node that message was sent
to, or timeout.
8 NAKs sent - no memory was available.
9 NAKs sent - message had undefined LSAP.
10 Duplicate messages received.
11 Token pass retries.
12 Packets received that were aborted early.
13 Packets received that had a CRC error.
14 Packets received that had an illegal size (greater than 271 bytes or
less than 3 bytes).
15 Duplicate tokens detected.
16 Node recoveries from duplicate node condition.
17, 18 Link dead timeouts.