Coral FlexiCom 6000 Installation Manual
Common Control Cards
8-99
PB-A
T
S
Peripheral Buffer Unit
8
8.6
PB-ATS
Peripheral Buffer Unit
The PB-ATS cards are installed in the peripheral shelves, in slot 1 and 2.
The PB-ATS cards are the Peripheral Buffer (PB) units, which function as the signal
regenerator for the peripheral shelves since the peripheral shelves can be located in the
same cabinet as the control shelf or physically further, in an expansion cabinet.
Two PB-ATS cards are provided for each Peripheral Shelf Unit in the Coral
FlexiCom 6000 system to provide redundant backup coverage even though one
PB-ATS is enough to control the Peripheral Shelf Unit. The second PB-ATS unit acts
as a
Standby
unit ready to take over the functions of the
Active
PB-ATS card.
The
Active
PB-ATS card provides buffers for the High-level Data Link Control
(HDLC), Pulse Code Modulation (PCM), Clocking and Synchronization signals,
exchanged between the 32GC card and the peripheral bus serving one or two
peripheral shelves.
The PB-ATS card also includes circuitry to allow/inhibit the PCM lines to the
peripheral cards, as well as a circuit for signal rate conversion from 8.192 Mbps to
4.096 Mbps for use in the peripheral shelves and vice versa. The PCM lines are
allowed in the
Active
PB-ATS card and inhibited in the
Standby
PB-ATS card. The
PB-ATS card transmits and receives HDLC messages using HDLC highway
A
or
B
in
accordance with its location in the peripheral shelf.
A fault in the interface between the PB-ATS cards and the peripheral cards of the
communication channel does not necessitate a switch-over on the control shelf
between the
Active
and
Standby
control card sets. It only necessitates the seamless
interchange between the two PB-ATS cards.
describes the interface between the control shelf and the peripheral
shelves in configuration type
H
and
H’
(see
Hot Standby Configurations beginning on page
for configuration types). In this diagram, the peripheral shelves are shown to
include two PB-ATS cards in slots# 1 and 2. A PBD-ATS card connects each pair of
PB-ATS cards, in which a connection exists between an even and an odd shelf, and
between each 32GC card and a PBD-ATS card.
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1
General Description
