Tadiran Telecom Coral IPx 500X, Инструкция по установке и справочник по аппаратной части

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Common Control Cards
8-27
PX Ca
rd
Peri
pheral
eXp
ansio
n Buff
er C
ar
d
8
8.10
PX Card
Peripheral eXpansion Buffer Card
3
The PX (Peripheral eXpansion) buffer card acts as a buffer between first and second
expansion cages of the Coral IPx 800 system. For that reason, the PX is installed in the
first expansion cage only when two expansion cages are installed in the system. The
PX card is installed in slot #1 of the first expansion cage whenever a second expansion
cage is installed.
The PX card buffers PCM streams, HDLC highway, and clock & sync signals to the
second expansion cage. If the second expansion cage malfunctions, the PX card
prevents the malfunction in the second expansion cage from affecting the first
expansion cage, and the system continues to function with the main cage and the first
expansion cage fully operational.
Figure 8-5
displays the block diagram for the PX card. PCM and HDLC signals are
received from the Coral IPx 800M main cage and transmitted via the PX buffer card to
the second expansion cage. The second expansion cage transmits PCM and HDLC
signals to the main cage via the PX card.
Figure 8-5 PX Buffer
Card Block Diagram
1 General Description
PCM A Rx
PCM A Rx
HDLC A Rx
Sync A
CLOCK A
PCM A Tx
HDLC A Tx
PCM A Tx
Sync A
Sync B
CLOCK B
HDLC B Rx
HDLC B Tx
HDLC A Rx
HDLC A Tx
HDLC B Rx
HDLC B Tx
Sync B
CLOCK A
Highway 4
Highway 3
Highway 2
Highway 1
T
o
M
a
in C
age
To
S
e
c
o
n
d
Exp
ansion Cage
Highway 4
Highway 3
Highway 2
Highway 1
CLOCK B