Nortel Circuit Card, Installation Manual, Page: 858 / 908

Page 858 of 906 QPC513 Enhanced Serial Data Interface card
553-3001-211 Standard 3.00 August 2005
Electrical interface options
Interface options are selected by inserting jumper plugs into the appropriate
sockets on the card:
• RS-232-C interface: The EIA RS-232-C interface can be used for speeds
up to 19.2 kbps and distances of less than 15.24 m (50 ft). The ESDI card
supports a subset of the RS-232-C signals. See Table 268 on
page 859 .
• High-speed interface: The high-speed interface combines features of the
RS-422-A standard for the data and timing signals with standard
RS-232-C control signals. It is used when the signal rate is greater than
19.2 kbps and/or when the distance between the system and host is
greater than 15.24 m (50 ft). No modems are needed if the distance is less
than 30.48 m (100 ft).
The high-speed interface uses a proprietary pin assignment, rather than
the standard 37-pin RS-449 arrangement. This pin arrangement is
compatible with the Spectron Cable #75-025 for V.35 use. See Table 269
on
page 860 .
The data and timing signals on the high-speed interface use RS-422-A
type differential line drivers and receivers in a balanced configuration.
These drivers and receivers are able to drive higher data rate signals over
longer distances than standard RS-232-C drivers and receivers. A typical
connection using these drivers and receivers is shown in Figure 184.
Figure 184
Typical high-speed interface line driver and receiver
Driver
Front panel
connector
Front panel
connector
System cable
Lead A
Lead B
Lead A
Lead B
Receiver
553-5943