Telecommunications Techniques Corporation interceptor 147, Reference Manual, Page: 78 / 280

3
Setup Categories
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INTERCEPTOR 147 2 Mbit/s and Data Analyzer
Bit position 1 can also be edited if Framing is set to FAS
or MFAS. However, when Framing is set to FAS-CRC or
MFAS-CRC, an uppercase “C” is displayed in bit position
1 and cannot be edited. The “C” indicates that this bit is
used to send CRC-4 error detection codes.
Bit 2 is always set to 1. In bit position 3, an uppercase “A”
is displayed when the test instrument is generating a FAS
Distant alarm (Tx Alarm = FAS ON), or a lowercase “a”
when it is not (Tx Alarm = FAS OFF).
In bit position 6, an uppercase “L” is displayed when the
test instrument is generating Sa6 loopcodes.
3.5.3 Tx MFAS
Use the Tx MFAS (Transmit MFAS) item to specify the
MFAS byte, which is transmitted in Timeslot 16 of the
first frame of every multiframe in all MFAS and MFAS-
CRC formatted 2Mbit/s signals. As shown in the following
diagram, you can specify the values for bits 5, 7, and 8 of
the MFAS byte.
Bits 1 through 4 of the MFAS byte always contain the
multiframe alignment signal 0000. In bit position 6, an
uppercase “A” is displayed if the test instrument is
generating an MFAS Distant alarm (Tx Alarm = MFAS
ON), or a lowercase “a” when it is not (Tx Alarm = MFAS
OFF).
Transmitted MFAS Alarm:
A = on; a = off.
MFAS
These bits may be edited.
Tx MFAS 000
xaxx