User Manual

ADCP-XX-XXX • November 2000 • Section 2: WMTS Description
Page 2-6
 2000, ADC Telecommunications, Inc.
system, and supports several independent functions, such as the control and forward
application, or downstream and upstream modem applications. The card is configured
according to its location in the enclosure. When the downstream card is installed in the
associated rear slot, it implements the downstream modem application. When the upstream
card is installed in the associated rear slot, it implements the upstream modem application.
When the universal card is installed immediately adjacent to the host card, it implements the
controller and forwarder (C&F) application, which handles the traffic over the local network
connection. The universal card communicates with the other system assemblies via the CPCI
bus, which is part of the chassis assembly. An internal system bus is used for front-to-rear slot
data transfer communications.
2.3.2 Downstream Card
The downstream (modulator) card, which is labeled Downstream, can be located in any of the
right six slots on the rear of the chassis. Typically, it resides in the far right slot. This
downstream card, when positioned to the rear of a universal card, becomes the downstream
module. The downstream module core also provides forward error correction (FEC), signal
modulation, and IF front-end.
2.3.3 Upstream Card
The upstream (demodulator) card, which is labeled Upstream, can be located in any of the
right six slots on the rear of the chassis. The upstream card, when positioned to the rear of a
universal card, becomes the upstream module. The upstream module core also provides
forward error correction (FEC), demodulation, and IF front-end.
2.3.4 Host Card
The host card is a faceless card whose front panel resembles a blank insert. There are no LED
indicators on this card. This card contains logic that arbitrates all WMTS communication on
the CompactPCI bus.
When the WMTS powers up, the channel numbers on the universal cards show as dot matrix
question marks. As the unit performs a self-test, the system recognizes the cards and the
correct channel number will appear in the dot matrix. Channel numbers occur sequentially as
1, 2, 3… starting at the leftmost universal card (when facing the WMTS). If a host card is not
functioning properly, this start-up sequence will not complete.
2.3.5 Downstream Application
The downstream application is loaded in the universal card, which is part of the downstream
module. The application provides the proper IF signal to be converted for the downstream
channel.