Computer Hardware Installation Guide

Engineering guidelines 397
The MSDL card addresses are set using decimal switches located on the
card. These switches can select 100 unique card addresses from 0 to 99.
An address conflict may occur between the MSDL and other cards because
of tr uncated address decoding by the other cards. For example, if a DCHI
port is set to address 5, it’s companion port is set to address 4, which means
that none of the MSDL cards can have hexadecimal address numbers 05H,
15H, É75H, nor addresses 04H, 14H, É74H. To avoid this conflicts system
software limits the MSDL card addresses from 0 to 15.
Port specifications
The MSDL card provides four programmable serial ports configured with
software as well as with switches for the following modes of operation:
Transmission mode Configure an MSDL port for synchronous or
asynchronous data transmission using LD 17.
Synchronous transmission uses an external clock signal fed into the MSDL.
Table 170 "Synchronous interface specifications" (page 397) lists the
synchronous interface specifications and the means of configuring the
interface parameters.
Table 170
Synchronous interface specifications
Parameter
Specification Configured
Data bits In packets-Transparent N/A
Data rate
1.2, 2.4, 4.8, 9.6, 19.2, 38.4,
48, 56, and 64 kbps
Software
Transmission Full Duplex N/A
Clock Internal/External Software
Interface RS-232 Software
RS-422 Switches
Mode DTE or DCE Switches
Asynchronous transmission uses an internal clock to generate the
appropriate baud rate for serial controllers.
Table 171 "Asynchronous interface specifications" (page 398) lists
asynchronous interface specifications and the means of configuring
interface parameters.
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23 May 2008
Copyright © 2003-2008, Nortel Networks
.