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6.2.7

Video

Output

The

video

output

circuit

converts

serial

data

input

from

the

video

converter

into

video

outputs

to

the

monitor

circuits

and

an

optional

monitor

device.

The

video

output

circuit

(Figure

6-27)

consists

of

the

following

components/circuits.

•

Data

gate

--

is

an

exclusive

OR's

serial

input

from

video

converter

with

REV/NORM

condition

from

attribute

logic

to

generate

a

high

output

(bit

"on"

condition)

when

REV/NORM

is

low.

I

L.._

TO

MONITOR

CIRCUITS ON

PS

AND MTR

BOARD

{

HOR SYNC l

FROM

-------tooI

SYNC

9007

__

VE_R_T_SY_N_C_l_~B_U_F_FE_R_S

1"----

......

fiNPU~~

:~'

~

14rlCt5MPOs.TIVI0E0

- - -

.,

'

STAGE

II

OUTpuT

STAGE

+12V

I

ro..

TVBH

R14

I

DUART

'I

I

""1'"

C R

I

'It

55 13

(REV/NORM, I

~

II R

FROM (

BUN'

!-' I I '

I·

I

~7

;6

15

ATIRIBUTE-<

I I :

,i

C I

CIRCUITS I I I

II

I

l'

56

4 I

l BOLD H J I D

,I

I

..-

FROM

TSlK.

l

P-H.

~

! L

--1-

- - -

_..J

BLA'"

--~:...:...........;,.+------

iii

_

CIRCUITS

I.

I fV!DEO OUTPUT ST.AGE""',

r--

- -

-1-'

I I II

+,2

V

I

DATA

! I

I.

.

~:~

I

I

I

GATE

I

'I·

: I

R~:

I

FROM ISERIAL DATA! I

~

I I I I

VIDEO I

~

, R20

CONVERTER L

--

- - -

_J

I I

_____

-.1

Figure

6-27

Video

Output

Block

Diagram

6-30

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