Rockwell Automation 1770, D17706.5.16 Ref Mnl DF1 Protocol Command - Manual (Page 139)

Chapter
9
Publication 1770Ć6.5.16 - October 1996
Diagnostic Counters
Diagnostic counters are bytes of information stored in RAM in each
module. The counters occupy a block of the module’s internal
scratch RAM. Most are single-byte counters that wrap around to
zero when they overflow. They are used to record events that can be
used in debugging and long-term reliability analysis.
These counters provide a useful tool for diagnosing problems.
For example, the ACK timeout counter and the false poll counter are
useful for diagnosing bad cabling, a noisy link, or an overloaded link
installation. You can also use the counters to determine the ratio of
messages transmitted (successfully returned an ACK from the
remote node) versus the commands sent.
This chapter lists interface module diagnostic counters and describes
what they contain. It contains these sections:
Section Page
1747 Cat. Nos. 9-3
1761 Cat. Nos. 9-7
1770 Cat. Nos. 9-8
1771 Cat. Nos. 9-14
1775 Cat. Nos. 9-21
1779 Cat. Nos. 9-24
1784 Cat. Nos. 9-25
1785 Cat. Nos. 9-26
5250 Cat. Nos. 9-33