Nortel Networks Circuit Card 311 - Manual (Page 944)

944 NTAK79 2.0 Mb PRI card
The D-channel support interface is a 64 Kbps, full-duplex serial bit stream
configured as a DCE device. The data signals include:
• Receive data output
• transmit data input
• receive clock output
• transmit clock output
The receive and transmit clocks vary in bit rate between each other, as
determined by the transmit and receive carrier clocks.
The NTAK79 has an onboard D-Channel Handler Interface (DCHI). It is the
equivalent to a single port of an NTAK02 SDI/DCH pack. This enables for
a completely operational ISDN PRA link with clock synchronization and
D-channel on a single circuit card.
The onboard D-channel has one status LED on the NTAK79 faceplate to
indicate enabled/disabled states. See
Table 377 "NTAK79 LEDs" (page
926) .
The on-board DCHI can be operated in two separate modes as defined by
an on-board dip switch. It can operate in a standard DCHI mode common
to most ISDN standard countries. The U.K. specific mode that uses the
DPNSS format is not supported at this time.
Table 398
Settings for the DCHI dip switch (SW1)
Switch Function On Off
S1-1 En/Dis Enabled Disabled
S1-2 F/W Mode DPNSS (not
supported at
this time)
DCHI
DCHI special applications connection
The connection between the PRI2 and the on-board D-channel Handler
Interface card is also available at the MDF connector. Connections are
made to these pins for normal on-board DCHI operation. They can also be
used for future or special applications.
The signals conform to the EIA RS-422 standard.
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23 May 2008
Copyright © 2003-2008, Nortel Networks
.