ACC X.25 Protocol User's Guide

X.25 Status and Completion Messages
Unsolicited Status Messages
Appendix A134
an enable of the X.25 link ZLU. Most likely the remote
end of the link is not responding to the HDLC/LAP-B
protocol packets sent by the ACC.
If bit 7 = 0, then the link is up (at level 2).
ST25DSBL (65) The X.25 link has been disconnected due to a disable
request on the X.25 link ZLU.
ST25XDCD (66) X.25 Link disconnected or restarted due to loss of DCD.
Bit 7 of the mrqstat field will indicate the current
up/down state of the link.
ST25XCTS (67) X.25 Link disconnected or restarted due to loss of CTS.
Bit 7 of the mrqstat field will indicate the current
up/down state of the link.
ST25RTRY (68) X.25 Link disconnected or restarted due to
retransmission counter N2 being exceeded. Bit 7 of the
mrqstat field will indicate the current up/down state of
the link.
ST25TXFR (69) X.25 Link disconnected or restarted due to a
transmitted FRMR (Frame Reject). Bit 7 of the mrqstat
field will indicate the current up/down state of the link.
ST25RXFR (70) X.25 Link disconnected or restarted due to a received
FRMR frame. Bit 7 of the mrqstat field will indicate the
current up/down state of the link.
ST25RXDM (71) X.25 Link disconnected or restarted due to a received
DM (Disconnect Mode) frame. Bit 7 of the mrqstat field
will indicate the current up/down state of the link.
ST25RXSA (72) X.25 Link disconnected or restarted due to a received
SABM (Set Asynchronous Balanced Mode) frame. Bit 7
of the mrqstat field will indicate the current up/down
state of the link.
ST25RXDI (73) X.25 Link disconnected due to a received DISC
(Disconnect) frame. Bit 7 of the mrqstat field will
indicate the current up/down state of the link. For this
particular status code, bit 7 should always be set to 1
indicating the link is down.