Nortel Networks Circuit Card 311 - Manual (Page 424)

424 NT7D16 Data Access card
connection. For example, if the equipment is turned off, the DAC
interprets that signal as an idle connection.
• Long break The user sends a break (transmit line held in the OFF or
SPACE state) for more than 1.2 seconds. The break is not transmitted
to the far end. At the end of the long break, the DAC port initiates call
disconnect. The AILU converts the dropping of DTR into a long break for
the RS-422 interface. The long break feature can be disabled through
the Modify menu on the DAC port.
• Three short breaks When the user equipment transmits three breaks
to the far end, the DAC abandons the call. Note that the breaks must
be spaced at least 10 msec apart, and all three must occur within 3
seconds.
Make Port Busy on loss of DTR
This feature is implemented by means of the Make Set Busy (MSB) station
feature. When this is activated, any attempt to reach the specified Data
DN results in a busy signal.
This application, which operates only in the RS-232-C mode, requires
a non-standard RS-232-C interface. Only two of the possible sixteen
RS-232-C modes can be used: Mode 8 (DCE, Host, Normal DTR, Manual
dial), and Mode 12 (DCE, Terminal, Normal DTR, Manual dial). This feature
is configured in the software, and is downloaded to the DAC.
A DTR timeout period is started whenever the DTR signal lead makes the
transition to OFF. If DTR is returned to ON within the set time period (5
seconds), the DAC port operates as if this feature was not activated. If the
DTR remains OFF beyond the 5 seconds, the system receives an MSB
feature key message. The DAC sends another MSB message when the
DTR returns to ON, and the port is able to receive inbound calls.
Note: If this feature is active, and the port is connected to a DTE that
holds DTR OFF when idle, then the port is permanently busied out to
inbound calls following the DTR timeout period.
Inactivity timeout
Once a successful data call is completed, the user’s activity is monitored. If
no activity occurs within the amount of time configured in the downloaded
parameters, the DAC releases the call. Three minutes before the inactivity
timeout takes place, the DAC sends a warning message to the near-end
equipment if terminal mode is selected.
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23 May 2008
Copyright © 2003-2008, Nortel Networks
.