Digi TransPort WR11 User Manual page 617

Configuring legacy protocols
Mode DTE or DCE
Determines whether LAPB will behave as DTE (Data Terminal Equipment) or DCE (Data Circuit-
terminating Equipment) in an X.25 protocol sense. Physical DTE vs. DCE wiring cannot be
changed by configuration.
N400 Counter x
This is the standard LAPB retry counter. The default value is 3 and it should not normally need
to be changed.
RR Timer x milliseconds
A standard LAPB Receiver Ready timer. The default value is 10,000 milliseconds (10 seconds)
and it should not normally be necessary to change this.
T1 Timer x milliseconds
A standard LAPB timer. The default value is 1000 milliseconds (1 second) and under normal
circumstances, it should not be necessary to change it.
T200 Timer x milliseconds
The standard LAPB re-transmit timer. The default value is 1000 milliseconds (1 second) and
under normal circumstances, it should not be necessary to change it.
X.25 Window Size
The X.25 window size. The value range is from 1 to 7 with the default being 7.
Disconnect link if there has been no X.25 activity for x seconds
The length of time, in seconds, before the link is disconnected if there has been no X.25 activity.
If this parameter is 0 or not specified, then the inactivity timer is disabled.
Disconnect link if there has been no activity for x seconds
The length of time, in seconds, before the link is disconnected if there has been no activity. If
this parameter is 0 or not specified, then the inactivity timer is disabled. It is useful to set this
to a short period of time, for example, 120 seconds, when using a LAPB instance over ISDN; for
example, with TPAD. Should the POS device fail to instruct TPAD to hang up you can use this
timer as a backup hang-up timer thus saving ISDN call charges. When using LAPB on a
synchronous port, set this parameter to 0.
Send X.25 Restart packet on receipt of SABM frame
This parameter can be set to No or Immediate.
When set to Immediate, the LAPB instance sends an X.25 restart packet immediately
n
on receipt of an SABM (Set Asynchronous Balanced Mode) frame.
If the parameter is set to No, no X.25 restart is sent.
n
ISDN Parameters
Allow this unit to answer calls
If enabled, this instance of LAPB answers incoming ISDN calls.
Digi TransPort® Routers User Guide
Configure X.25 parameters
617