Rockwell Automation 1770-KF2 Data Highway or Highway Plus Interface Module User Manual - Manual (Page 191)

Error Reporting
Chapter 7
7Ć36
27. Reply messages sent.
28. Not used.
MODEM CHANNEL COUNTERS
29. Command messages sent.
30. Not used.
31. Reply messages received.
32. Not used.
33. Command messages received.
34. Not used.
35. Reply messages sent.
36. Not used.
37. ACKs received.
38. Not used.
39. ACKs sent.
40. Not used.
41. NAKs received.
42. Not used.
43. NAKs sent.
44. Not used.
45. Undeliverable reply messages.