ACC X.25 Protocol User's Guide

ZX25D X.25 Protocol Driver
Implementation Notes
Chapter 3 61
Error Handling
The ZLU error counter for the X.25 link ZLU is incremented whenever
an invalid frame is received, any frame needs to be re-transmitted or a
FRMR (Frame Reject) frame is either transmitted or received.
These counters can be viewed via the tt and ttx commands of the ZMNTR
utility.
T28 - Not Supported
DCE - Optional Timers:
T10 - 60 seconds
T11 - 180 seconds
T12 - 60 seconds
T13 - 60 seconds