Nortel Networks Video Gaming Accessories 553-3001-211 Manual De Usuario

 NTBK50 2.0 Mb PRI card

The transmitter and receiver functions are used for synchronization, channel, 
and signal extraction. The functions meet applicable specifications of the 
CCITT recommendation G.703 and G.732.

The transceiver provides transmit framing based on the 2.048 MHz clock 
derived from the DS-30X system clock and 1 KHz framing pulse.

Slip control provides organized recovery of PCM when the clock recovered 
from the external facility is at a different frequency with respect to the local 
clock. 

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 can be of slightly different bit rates from each 
other as determined by the transmit and receive carrier clocks.

The NTBK50 supports a D-Channel Handler Interface (DCHI) 
daughterboard. It is equivalent to a single port of an NTAK02 SDI/DCH card. 
The NTBK50 also supports a Downloadable D-Channel Handler interface 
(DDCH) daughterboard. The DDCH brings MSDL D-channel capability to 
the system. 

The NTAK93 DCHI daughterboard can be operated in two separate modes 
defined by an on-board dip switch. It can operate in a standard DCHI mode 
common to most ISDN standard countries. It can also operate in a DPNSS