ACC X.25 Protocol User's Guide

X.25 Status and Completion Messages
Unsolicited Status Messages
Appendix A 135
ST25RXUA (74) X.25 Link disconnected or restarted due to a received
UA (Unnumbered Acknowledgment) frame. Bit 7 of the
mrqstat field will indicate the current up/down state of
the link.
ST25RUFR (75) X.25 Link disconnected or restarted due to a received
unsolicited final response frame. Bit 7 of the mrqstat
field will indicate the current up/down state of the link.
ST25ENF (77) X.25 Link ZLU enable failed due to an invalid
configuration. Check the various configuration
parameters, particularly the poll and select words for
this X.25 link ZLU.
ST25ENB (78) X.25 Link ZLU has been enabled.
ST25TPA (79) X.25 Link ZLU has been activated. This link can now
accept inbound I-frames.
ST25TPD (80) X.25 Link ZLU has been deactivated. Note that a
deactivated link will not accept inbound data. The ACC
MUX will automatically respond with a level 2 RNR
when the remote side of the link attempts to send an
HDLC/LAP-B I-frame to a deactivated link.
ST25DSBRQ (81) A DISABLE request has been issued to this X.25 link
ZLU. This status normally begins the link shutdown
process. When the shutdown processing is complete, a
link disabled status (82) is received.
ST25DSB (82) X.25 link ZLU has been disabled. The X.25 link is now
fully shutdown and will not respond to any
HDLC/LAP-B protocol packets.
ST25LNCTO (83) An X.25 link control timeout has occurred. This
indicates that the remote end of the link has not
responded to a protocol packet within the appropriate
amount of time. For example, when a Restart Request
packet is sent, the remote end must respond within
timer T20 seconds. This status message is sent when
the timer expires without having seen a response from
the remote end of the link.
ST25LNNBF (84) X.25 link buffer shortage has occurred. This indicates
that the MUX firmware was unable to find a free
outbound buffer for sending a low-level protocol packet
(e.g. RR or RNR). This can be caused by applications