Nortel Networks Circuit Card 311 - Manual (Page 446)

446 NT7D16 Data Access card
Mode of
operation
Interface application Comments
DAC drops DTR if the remote modem sends a long
break or three short breaks. The modem must drop
DCD.
Call disconnection (modem):
Modem drops DCD (DCD OFF for 100 ms or more).
The DAC drops DTR and disconnects the local call.
Modem drops DSR (DSR OFF for 100 ms or more).
The DAC drops DTR and disconnects the local call.
Mode 1 Inbound Hotline modem
pools
Most dumb modems can be
used for this application.
Inbound Hotline modem pooling:
Modem sends ring/no ring cycle (2 seconds ON, 4
seconds OFF) to initiate connection.
DAC responds by trying to establish a Hotline call to
a specific Data Module (Autodial).
When Data Module answers, then and only then, the
DAC turns DTR ON.
Modem should answer the incoming call when DTR
goes ON and should turn DCD ON within 35 seconds;
otherwise the DAC disconnects the call.
Call disconnection:
Disconnection is the same as mode 0.
Mode 2 Inbound and Outbound
modem pools (with forced
DTR)
Use this mode with Hayes
1200 modem.
Inbound and Outbound modem pooling:
The DAC operation is identical to mode 0 except that
DTR is always forced ON (except during disconnect).
Call disconnection:
Disconnection is identical to mode 0 except:
—When a call is released, the DAC turns DTR OFF
for 0.2 second and then ON. DTR stays ON until the
next call release.
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23 May 2008
Copyright © 2003-2008, Nortel Networks
.