REFERENCE TIMER (RT) CARD

T.O. 31W-2GSC24-2

TM 11-5805-688-14-1

NAVELEX 0967-LP-545-3011

serviced, are generated and applied to the select inputs

5-101. The output data multiplexer interleaves, one bit

on the output data multiplexer. Each used port in an

at a time, the data inputs from each of the active

active channel in the multiplexer receives one gated

channels and the overhead data input

from the

clock signal that gates one data bit to the GC/DM card

overhead data multiplexer. The high-speed serial data

during each word time; the exception is during word 29

stream (MSD) from the multiplexer is applied to the RT

when overhead servicing is performed. When positive

card. The 4-bit binary channel address signals GCAD1

stuff enable signal MPSE is applied to the circuits during

through GCAD8 select the appropriate overhead or data

word 29, one additional gated clock signal is generated

channel input to the multiplexer at the system clock rate

to the active channel selected for overhead servicing. In

MRIO. The channel address applied to the multiplexer

turn, when negative stuff enable signal MNSE is applied,

is the same channel address in the gated clock signal

one gated clock signal, which is normally applied to the

that is generated at any given time. For example,

selected active channel, is deleted as part of the

channel 2 is receiving a gated clock signal MGC02 at

overhead service function.

the same time that the channel address signal for

channel 1 is applied to the multiplexer. The high-speed

5-100. The overhead data multiplexer combines the

serial data stream is clocked out of the multiplexer by

overhead data inputs for a given port selected for

system clock signal MRIO.

overhead servicing into a serial format. The serial

overhead data are clocked into the output data

5-102. REFERENCE TIMER (RT) CARD.

multiplexer during bit 0 of each data word period. Words

24 through 29 signal MWC2429-enables minor frame

5-103. The RT card produces system clock signal Ro

count signals MMFCO through MMFC4 to be applied,

and timing signals T3600 and T4800 used in the

one bit at a time, to the overhead data multiplexer.

multiplexer cards. The high-speed serial data stream

Word count signals WCO, WC1, and WC2 sequentially

(MSD) from the GC/DM card is conditioned in the RT

clock the five minor word count signals into the output

card and is then applied, with associated timing signals,

data multiplexer. The appropriate 23-bit stuff code

to the rear panel, where the signals are fed into a

clocked into the overhead data multiplexer during words

balanced or unbalanced cable system.

1 through 23 is selected by positive stuff request signal

MPSA or negative stuff request signal MNSA from the

5-104. The high-speed serial digital data stream from

OEG card. The absence of both signals from the OEG

the GC/DM card is clocked into the output data line

card enables the no-action code. When signal MPSA is

driver by system timing signal Ro. The digital data are

applied to the multiplexer, positive stuff enable signal

conditioned into digital signals that can be applied to a

MPSE is generated and applied to the gated clock

balanced line or an unbalanced line input. In a balanced

generation circuits. When signal MNSA is applied to the

line configuration,

the output data signals are

multiplexer, a negative stuff enable signal is generated

transmitted as complementary serial data out signals

and applied to the gated clock generation circuits. The

SDATO and SDATO-.

In the unbalanced line

output from the overhead data multiplexer is the serial

configuration, signal SDATO-is terminated (grounded).

29-bit overhead message that is applied to the output

System

data multiplexer during bit 0 of words 1 through 29.

5-25