OVERHEAD ENABLE GENERATOR (OEG) CARD

T.O. 31W2-2GSC24-2

TM 11-5805-688-14-1

NAVELEX 0967-LP-545-3011

The count three is produced by the high inputs to the

signals to the FS card at this time. Count 12 is also

count one and count two preset inputs on U9 from

applied through word count signals DWCO through

inverter U4-2. The circuits just de- scribed are reset to

DWC4 to the OEG card at this time.

ensure that the next end-of-scan timing signals are

produced at the proper time when the next A=B signal is

5-466. In the gated clock generation function, gated

generated from ports- in-use comparator U34.

clock signals DGCO1 through DGC15 are applied to the

de- multiplexer channel cards. Overhead count signals

DOHO through DOH3 apply overhead address signals to

5-463. GATED CLOCK/DATA MUX (GC/DM)

the display card and the OEG card. In turn, de-

CARD.

multiplexer channel address binary signals DCHA1

through DCHA8, which select the channel to be serviced

5-464. The GC/DM card used in the de- multiplexer is

at a given time, are supplied from the seq card.

the same card type as that used in the multiplexer. The

GC/ DM card requires no functional modifications for use

5-467. The data multiplexer functional circuits on the

in the demultiplexer. As described in the following

GC/DM card are not used in the demultiplexer function.

discussion, all the circuits on the GC/DM card are not

Functional operation of the diagnostic circuits on the

used in the demultiplexer. The GC/ DM card logic

GC/DM card in the demultiplexer is the same as that in

diagram identifies the input and output signals that are

the multiplexer.

applicable to the multiplexer function, and those that are

applicable to the demultiplexer function. The signals

5-468. OVERHEAD ENABLE GENERATOR (OEG)

prefixed by a D are applicable to the demultiplexer, and

CARD.

those prefixed by an M are applicable to the multiplexer.

Signals not prefixed by a D or an M are used in both the

5-469. The OEG card used in the demultiplexer is the

demultiplexer and the multiplexer. The following detailed

same card type as that used in the multiplexer. The

circuit discussion supplements the GC/ DM card theory

OEG card re- quires no functional modifications for use

of operation in para- graph 5-306.

in the demultiplexer. As described in the following circuit

discussion, all the circuits on the OEG card are not used

5-465. In the format generation function, word counter

in the demultiplexer. The OEG card logic diagram

preset signal DWPR- is applied to inverter U15-8 when

identifies the input and output signals that are applicable

the equipment is initially turned on or frame

to the multiplexer function, and those that are applicable

synchronization has been lost. Signal DWPR- is

to the demultiplexer function. The signals prefixed by a

produced on the FS card as part of the resynchronization

D are applicable to the demultiplexer and those prefixed

function that involves the seq and GC/DM cards. The

by an M are applicable to the multiplexer. Those signals

signal is applied through inverter U15-8, U13-6, OR

not prefixed by a D or an M are used in both the

gate U4-6, and inverter U13-2 to preset count 12 into

multiplexer and the demultiplexer.

word counter U5, U14. When the next end-of-scan

signal DEOS2B- is applied to the GC/DM card, word

5-470.

In the demultiplexer,

the negative stuff

counter U5, U14 is incremented to produce word count

multiplexers are not used.

12 to read only memory (ROM) U20. In turn, U20

generates bit 12 of the DNAC, DNSC, and DPSC

5-122