Nortel Networks Circuit Card - Manual (Page 386)

Page 386 of 906 NT6D71 UILC Line card
553-3001-211 Standard 3.00 August 2005
Power consumption
Power consumption is +5 V at 1900 mA.
Functional description
Each U interface provides two B-channels and one D-channel and supports
one physical termination. This termination can be to a Network Termination
(NT1) or directly to a single U interface terminal. Usually, this physical
termination is to an NT1, which provides an S/T interface that supports up to
eight physical terminal connections. The length of a DSL depends on the
specific terminal configuration and the DSL wire gauge; however, it should
not exceed 5.5 km (3.3 mi).
The main functions of the UILC are as follows:
• provide eight ISDN U interfaces conforming to ANSI standards
• support point-to-point DSL terminal connections
• provide channel mapping between ISDN BRI format (2B+D) and system
bus format
• multiplex four D-channels onto one timeslot
• perform activation and deactivation of DSLs
• provide loopback control of DSLs
Micro Controller Unit (MCU)
The Micro Controller Unit (MCU) coordinates and controls the operation of
the UILC. It has internal memory, a reset and sanity timer, a serial control
interface, a maintenance signaling channel, and a digital pad.
The memory consists of 32 K of EPROM that contains the UILC operating
program and 8 K of RAM that stores interface selection and other functions
connected with call activities.
The reset and sanity timer logic resets the MCU.