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Rev B
Doc. 6001072
Page 17 of 28
2. THREE DECADE LIB SWITCH
To make service and troubleshooting easier, we recommend organizing three decade switch
addresses as follows:
1. Switches S1 and S2 indicate the LIB housing number. For example
•
On boards in the
first LIB housing of a stack,
set S1 to 0 and S2 set to 1.
•
On boards in the
thirteenth LIB housing of a stack,
set S1 to 1 and S2 set to 3.
NOTE:
If there is only one LIB housing in your installation, set S1 and S2 on all LIBs to 0. This
allows you to use a 3 digit default directory code: 1 digit for the LIB and 2 digits for the LIB line
address.
2. Switch S3 indicates the LIB number within the housing. Number from right to left, starting
with 0. For example:
•
On the far right LIB in the housing, set S3 to 0.
•
On the LIB to its left, set S3 to 1, and so on.
•
Using this numbering scheme, the address of the fourth LIB from the right in the second
LIB housing is 023, because 02 is the
housing
number, and 3 is the
LIB
number.
Once the LIB addresses are set, determining the address of individual lines is easy. For
example:
♦
The third line on the the fourth LIB from the right in the second LIB housing is addressed
02303, because 02 is the
housing
number, 3 is the
LIB
number, and 03 is the
line
number.
♦
The eleventh line on that same board would have an address of 02311, because 02 is the
housing
number, 3 is the
LIB
number, and 11 is the
line
number.
♦
The same line addressing scheme is used on all boards. So the eighth line on the fifth board
from the right in the first LIB housing would have an address of 01408, because 01 is the
housing
number, 4 is the
LIB
number, and 08 is the
line
number.
NOTE:
These addresses are necessary to program and troubleshoot the system. Make sure
they are labeled on the associated RJ71C jack, and entered on the form in Figure 4, so they will
be available to assist you in programming, testing and troubleshooting the system.