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Circuit Card Description and Installation
826

NTRB21 DTI/PRI/DCH TMDI card

Contents
This section contains information on the following topics:
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 813
Physical description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 814
Functional description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 818
Software description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 819
Hardware description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 819
Architecture. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 819
Introduction
The NTRB21 (DTI/PRI/DCH) TMDI digital trunk card is a 1.5 Mb DTI or
PRI interface to the CS 1000S, CS 1000M Cabinet, and Meridian 1 PBX 11C
Cabinet. The NTRB21 card has a built-in downloadable D-channel.
The TMDI feature supports the software changes required for CS 1000S,
CS 1000M Cabinet, and Meridian 1 PBX 11C Cabinet to use the new TDMI
pack. The software changes include:
• a new prompt to replace a function that was handled by a dip switch on
the NTAK09
• an extra loadware application to handle Layer 1
• a change to the existing loadware files into 32 bit format from the
original 16 bit format