Mode 2 – Nortel Networks Circuit Card User Manual
Page 447
NT7D16 Data Access card
Page 447 of 906
Circuit Card
Description and Installation
Programing DAC for mode 1 in service change LD11
The DAC must be configured as R232 (the Autodial feature key is used for
this mode). The DAC must not be configured as an Asynchronous Data
Module (ADM) trunk.
Mode 2
This mode should be selected when the DAC is connected to a Hayes-1200
modem for inbound and outbound modem pooling. This mode is created
specially to resolve some problems that were encountered with this modem,
namely, the auto-reset implementation. When this modem is operating in the
auto-reset mode, it drives both RI and DCD ON as long as DTR is OFF. This
problem was resolved by driving DTR ON in the idle state, and OFF for 0.2
seconds, and then ON when an established call is dropped. The DAC also
ignores the status of RI and DCD for approximately 2 seconds after a call is
released to avoid false inbound call initiation.
Configuring Hayes 1200 for mode 2
To configure this modem, set the following parameters in LD11:
DEMDTE
PRMOFF
DTRON
HOTOFF
To configure this modem, set the configuration switches as follows:
•
switches 3, 8, and 10 to DOWN position
•
all other switches to UP position. Switch 7 should be UP when using
RJ-11 jack.
Programing DAC for mode 2 in service change LD11
When used for inbound or outbound Modem Pool only, the DAC can be
configured as R232 in LD11. When used for both inbound and outbound
Modem Pool, the DAC must be configured as R232. When the DAC is
programmed as station hunting, outbound modem access should be in the
opposite direction to the 500/2500 station hunting for the inbound modem
access.