CXR Larus 80-100-400
Issue 1, July 2006
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5−
12
Management Card and 54560 Alarm Interface Card.
e. Facilitates synchronization status messaging per Bellcore GR-378 (DS1
only).
5.52 Circuit
Description
Refer to the block diagram in Figure 5-4 during the following discussion.
5.5210 Microcontroller
The functions of the 54522 track and hold card are controlled by an 80C320
microcontroller. The 80C320 memory space consists of two 64K blocks of
memory, one each for program and data.
5.5211 DS1/E1
Input
The 54522 card gets its clock from the 54511 or 54512 Input Card. It selects
either the A or B input reference clock signal via the backplane connector. The
54522 can select Input B to be from Input Card A by activating the INPSEL
output line.
a. For the AB input architecture, the primary reference for the A track and
hold card is Input A and for the B track and hold card it is Input B.
b. For the AA input architecture, the primary reference for both track and hold
cards is Input A. In this state, the Input A LED is illuminated on both track
and hold cards.
Input references can only be changed by commands from a terminal as
described in the Volume 3 (TL1/ITL1) or Volume 4 (Menu) StarClock 200E
User Manual.
5.5212 T1/E1
Receiver
The T1/E1 receiver regenerates the selected incoming signal and recovers
both the clock and the data. The data go to the framing circuit. The 54522
measures the input T1/E1 reference bit time phase as compared to the
ovenized crystal oscillator output by means of a digital phase detector.