STARPLUS STSe Key System, Руководство по установке

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Expansion Board Installation 3-19
Chapter 3 - Installation
STARPLUS STSe - Installation Manual August 2005
Phase Lock Loop Unit
The Phase Lock Loop Unit (PLLU) is an option board
which generates a 32.768MHz clock synchronized to
1.544MHz from the T1 interface board or internal clock.
This board is required whenever a T1 card is installed in
the system. The 32.768MHz clock is provided to CGMD
on MBU. It consists of a PLL circuit, PLL Monitoring
circuit and clock (from T1 interface board) monitoring
circuit.
The PLLU is installed in the upper center of the BKSU.
Refer to
Figure 3-8: PLLU Location .
Installing the PLLU
1. Unpack the PLLU from its antistatic conductive
bag in the packing box.
2. Locate CN14 and CN15 on the MBU.
3. Remove the jumper from pins 12 and 13 on CN5.
4. Locate the CON1 and CON2 connectors on the PLLU board.
This jumper is very important, so don’t lose it. LOSS OF JUMPER ON CN5
12 & 13 WILL PREVENT SYSTEM OPERATION.
If the PLLU is removed from the
MBU board, this jumper needs to be put back onto pins 12 and 13 of this
connector or the MBU does not operate properly.
It is recommended that you tape the jumper to the board.