ERROR RATE DETECTOR (ERD) CARD

T.O. 31W-2GSC24-2

TM 11-5805-688-14-1

NAVELEX 0967-LP-545-3011

error counts from the FS card: three that are associated

5-121. The stuff code generation circuits produce the

with the positive stuff command codes; three that are

three stuff command codes that are applied to the FS

associated with the negative stuff command codes; and

card as part of the frame synchronization function.

three that are associated with the no-action command

End-of-scan signal DEOS2Bfrom the seq card is a timing

code. During word 28, only one set of error counts is

input to the circuits. During bit 0 of each word, one bit

monitored by the circuits. The set of three error counts

from each of the three stuff command codes is applied

monitored is selected by positive and negative stuff

to the FS card. When the demultiplexer has frame

command code signals DNSE and DPSE from the FS

synchronization, one of the three bits applied to the FS

card. When signal DNSE is applied, the error rate

card will compare with the equivalent bit in the incoming

detector circuits monitor the three bit error counts

overhead message format during words 1 through 23.

associated with the negative stuff command codes. The

positive stuff command codes are monitored when

5-122. The word generation circuits produce word count

signal DPSE is applied to the circuits. When both

signals DWCO through

DWC4 to provide 5-bit

signals (DPSE and DNSE) are absent during a given

sequential word counts 1 through 29 to the OEG card.

minor

frame period, the three bit error

counts

Word signals DW28 and DW29 are also produced by

associated with the no-action command codes are

the circuits. Word signals DW28 and DW29- are applied

monitored. When the number of errors identified in the

as timing signals to the ERD card and the FS card.

error counts exceeds a predetermined threshold count

Word signal DW29 is applied to the OEG card.

within a given period of time, link error rate signal LLER

is generated. Signal LLER causes the LINK ERROR

RATE indicator on the front panel to light. When the

5-123. ERROR RATE DETECTOR (ERD) CARD.

number of errors detected within a given period of time

decreases to a value that is less than the predetermined

5-124. The ERD card generates a timing signal and

threshold count, signal LLER is removed and the

monitors the incoming serial data stream for errors to

indicator goes out.

establish confidence in the BCI of the incoming data.

The minor frame generation circuits produce minor

frame count signals DMFCO through DMFC4 that are

5-126. SMOOTHING BUFFER (SB) CARD.

applied to the seq card. The minor frame identified in

the signals is the same minor frame that is identified in

5-127. The SB card receives the high speed serial data

the incoming overhead message format at any given

in the form of synchronous data (DTIX-) from the FS

time. Timing signals DW28, DW29-, and DEOS- are

card. The SB card function is basically the complement

used in the generation of the minor frame count signals.

of the RCB card function performed in the far-end

Demultiplexer overhead data

signals DOD-, which

multiplexer. Each SB card demultiplexes one channel of

contain the minor frame count for the minor frame in a

data out of the high-speed serial data stream and

given overhead message during a minor frame period,

converts the data into the original asynchronous data

are used to synchronize the minor frame generation

format (with timing) that was applied to the far-end

circuits.

multiplexer. This card also demultiplexes data originally

processed into the far-end multiplexer by

5-125. The error rate detector circuits receive nine bit

5-29