User's Manual

32 Chapter3
Using HDLC/LAP-D Protocol
Status and Error Messages
Status and Err or Messages
HDLC/LAP-D produces a range of buffer status codes and unsolicited
status messages, apart from the standard communications s tatuses
described else where in the ACC documentation. In the following
descriptions, the statuses marked with a dagger (†) are not generated by
UI terminals. The defines for these status codes are located in
/usr/include/zcom/zcomstatus.h and /usr/include/zcom/zx25status.h.
Terminal Request Status Codes
Thefollowingstatusesarereturnedinresponsetoarequesttocreate,
destroy, enable, disable, activate or deactivate a terminal. Although
these are a part of the standard status set, they are not used by all
protocols, and have a particular significance within HDLC/LAP-D
.
0 TM_OK No error detected
The request was successfully processed. In the case of
enabling or disabling the terminal, this does not mean
that the link has been established or disconnected. The
link status is reported via unsolicited status messages.
1 TM_MUST_DSBL Terminal must be disabled
This status code is returned in response to a terminal
delete request. Before deleting a terminal, it must be
disabled and the ST25DSBL unsolicited status message
must have been received.
12 TM_PROT_REJ Protocol detected error
TM_PROT_REJ is returned in response to a terminal
enable request when the configuration specified by the
poll, select and option words is invalid. In addition to
returning TM_PROT_REJ, the protocol generates a
ST25ENF unsolicited status message. For configuration
information, Chapter 4 , “Protocol Specific
Configuration.” Another possible, although unlikely,
cause for TM_PROT_REJ is that an error occurred when
the protocol attempted to setup a group of LAP-D
terminals. In this case, the ST25ENF unsolicited status
message will not be generated.