Lear Seigler ADM-3A Maintenance Manual

ADM-3A

Maintenance Manual

TABLE

OF

CONTENTS

Section

1

2

3

GENERAL

1.1

1.2 ADM-3A

1.3

1.4

INSTALLATION

2.1

2.2

2.3

2.4

2.5

2.6

2.7

OPERATION

3.1

3.2

3.3

3.4

DESCRIPTION

INTRODUCTION.

PHYSICAL SPECIFICATIONS.

GENERAL. VISUAL INSTALLATION. SETTING SETTING SETTING CONNECTING

GENERAL. DISPLAYING SPECIAL PROGRAMMING&WORD

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CAPABILITIES

DESCRIPTION.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

INSPECTION

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

INTERNAL FRONT DISPLAY

FUNCTION

PANEL

CONTROL.

CABLES&TURNING

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

CHARACTERS

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SWITCHES.

KEYS.

STRUCTURE.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . .... . . . . .... . . .... . . . . . . . . . . .

ON

POWER.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

. . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

. . . . . . . . . . . . . . . . . . . . 2-4

Page

1-1 1-1 1-1

2-1 2-1 2-1

..

2-3

..

2-4

. . 3-1

4

5

6

THEORY

4.1

4.2

4.3

MAINTENANCE

5.1

5.2

5.3

5.4

5.5

5.6

DRAWINGS

6.1 SCHEMATIC

6.2

6.3

OF

OPERATION GENERAL. GENERAL LOGIC

GENERAL. INSTALLATION. ROUTINE OPENING ADJUSTMENTS CORRECTIVE

SYSTEMS SCHEMATIC INTERFACE

SCHEMATIC CLEAR/ERASE OFFSET

ROW BEEPER

DESCRIPTION

MAINTENANCE.

ADM-3A

COUNTERS.

COUNTER

COUNTER.

CIRCUIT.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

FUNCTIONAL

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

COVER.

MAINTENANCE

SHEET

SHEET#12 CONTROL. SHEET#3

LOGIC

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5

DESCRIPTION.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

#2

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .... .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4

. . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

~

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

..

. . 6-3

4-1

5-1 5-3

6-1

TABLE

OF

CONTENTS (Continued)

Section

6.4 SCHEMATIC COLUMN WRITE-PULSE

6.5 SCHEMATIC SHEET# 5 MEMORY ADDRESS GENERATION 6-6

6.6 SCHEMATIC DATA RECEIVER . . 6-7

CHARACTER DECODERS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

LOAD CURSOR SEQUENCE

6.7 SCHEMATIC

CLEAR CIRCUIT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8

READ BACK. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-10

MONITOR DRIVE CURSOR

6.8 SCHEMATIC REFRESH CHARACTER

VIDEO SERIALIZER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11

TRANSMIT DATA MULTIPLEXERS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11

6.9 SCHEMATIC SHEET KEYBOARD

6.10 SCHEMATIC

DATA TRANSMITTER. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-13

CONTROL SECTION

CURRENT LOOP XMTR/RCVR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-14

KEYBOARD LOCK CIRCUIT " 6-14

6.11 SCHEMATIC SHEET # BAUD RATE

SHEET#4

COUNTER.

LOGIC.

SHEET#6

SHEET#7

SIGNALS.

GENERATION.

SHEET#8

MEMORY.

GENERATORS.

#9

CIRCUIT.

SHEET#10

OF

GENERATION.

Page

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-6

DETECTOR.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-10

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-10

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-10

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-11

UART.

11

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-13

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-14

. . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8

6-5

..

6-8

7 PARTS

8 RETURNING EQUIPMENT

9

APPENDICES

A

B SCHEMATICS. . . . . .

C OPTIONS C-l

PAINT.

TIMING. MONITOR A-2

POWER SUPPLY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

P.C. BOARD ASSEMBLY " A-4

WIRING

LIST.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

FOR

REPAIR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

..

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

DIAGRAMS.

. . . . . . . . . . . . . . . . . . . . .... . .... . . . .... . . . . . . . . . . . . .

7-1

8-1

..

9-1

..

A-I

A-3

..

B-1

C-9

SECTION 1

GENERAL DESCRIPTION

1.1

INTRODUCTION

This manual contains a general description, instal-

and

lation

operation, Lear

Terminal.

Siegler

operating instructions, theory

and

maintenance information for the ADM-3A

Interactive

Display

of

g.

The terminal has the ability to recognize and

at

position the cursor screen.

h. The ADM-3A contains

which causes wrap-around

or

forward the cursor to be 'homed.'

downline operations and allows

any location on the

an

overflow detector

or

scrolling on

Additional information

3A Operator's Handbook. The maintenance

technician should be thoroughly familiar with

material in the Operator's

to

attempting

1.2 ADM-3A CAPABILITIES

The

ADM-3A

capabilities:

a.

Receives USASCII-coded

computer displaying up to 1920 characters.

b. Permits the operator, using a keyboard,

compose a message, visibleonthe screen as it is

transmitted to the remotecomputerorother

device.

Through

c.

interfacing with a hard-copy printer, magnetic tape recorder,

d. Provides for full-duplex

communications, or

e.

Permits 202 communications line

by means turnaround transmits a the deviceatthe other endofthe line), secondary-channel

secondary channel selection establishes control through

troubleshootorrepair the ADM-3A.

and

an

current-loop interface.

of

(in which the controlling device

turnaround

of

a device for

the primary channel).

is

contained in the

has

the

displays it

extension

or

other terminals.

through

either

EOT

codetogive control

turnaround

AD

Handbook

following

data

from a remote

onaCRT

port,

or

eitheranRS-232C

or

(in which a

data

transmission

before

general

screen

permits

half-duplex

turnaround

ETX code-

M-

to

to or

1.3 PHYSICAL DESCRIPTION

Principal components follows:

a. A molded case comprising a base and a cover.

The base contains the power switch, power transformer, intercomponent cabling. The main circuit board and

The cover contains the monitor other monitor subassemblies. the rear so

3A are accessible when itisopened. The cover is it will go, and then sliding it to the left, off the hinge pins. (The monitor-connecting cable must be disconnected.)

b. The main circuit

elements power switch, line fuse beeper speaker. The keyboard consists integrated key rows andisbuilt directlyonthe main circuit board.

The main circuit board rests within the base pins. Two connectors board (optional printer port) interface main and extension ports.

c.

The

subassemblies,

rests

is

held in place by two guide pins.

that

easily removed by swinging it backasfar as

of

provide the RS-232C

CRT

monitor which compnses three

of

the

ADM-3A

beeper

on

supports molded in the base

all componentsofthe

board

the

ADM-3A

andisheld in place by guide

-as

follows:

speaker,

CRT

It

is

hinged at

which contains all

except monitor,

and

transformer, and

on

the rear edgeofthe

and

current loop

at

are as

ADM-

supports

both

and

of

the

f.

Allows the

underline cursor which enters bottom

at

the

operator

line,ora reverse block cursor homed

top

leftofthe screen.

to select between a double

data

on

the

1-1

1.

The

CRT

itself, whichismounted in a metal frame with its face held against the cover bezel by two brackets, each retained by a single screw.

2.

A printed circuit containing most circuits The video cover molding of

the flyback assemblyonthe other.

boardisheld in place by the

board

on

one side, and by pressure

(video board),

of

the monitor.

KEYBOARD

59-key solid-state keyboard designed similar to a

and

teletypewriter layout keys:

containing the following

3.

The flyback assembly, whichisheld in place by a single screw. Bosses in the cover molding assembly surface retain the edge the video board.

1.4 SPECIFICATIONS DISPLAY Screen

12-inch (diagonally measured) rectangular

with

P4

white

surface.

Display Format

Standard:

Optional:

Character Set

Generated:

Displayed:

phosphor

960 characters, characters

1920 characters, 24 lines

characters

lL~

ASCII lower case, numeric, control)

Standard

Optional -

and

etched non-glare

12

lines

characters (upper

punctuation

- 64

ASCII (upper case, numeric, punctuation)

95

ASCII (upper and lower case, numeric, punctuation)

characters

of

CRT

80

and and

47 alphanumeric keys RETURN LINE RUB HERE SHIFT

COMMUNICATIONS Modem interiace

EIA (switch selectable)

Extension Interface

Extension RS-232C asynchronous auxiliary device (e.g., hard copy printer, magnetic terminals).

Optionally, the extension

RS-232C

Communication Rates

75, 110,

19200

Send/Receive Modes

Full duplex

FEED

IS

standard

and

150,

baud

RS-232C

tape

20mA current loop interfaces.

300,600, 1200, 1800, 2400, 4800, 9600,

(switch selectable)

and

half duplex (switch selectable)

and

port

recorderoradditional

portisavailable with

CTRL BREAK CLEAR REPT ESC (Escape) Space Bar

20mA current loop

for interfacing serial

(Control)

(Repeat)

data

both

Character Generation

5 x 7

dot

matrix, 0.18 in. high x 0.075 in. wide

Cursor (2 modes) -

(I)

Underline, homes to lower leftofscreen

(2) Reverse block image, homes

screen

Data Entry

New

data

entersonprogressive lines, oronbottom scrolling overflow,

Refresh Rate

60Hzor50Hz, dependentonan

to match power line frequency.

lineofscreen. Line feed causes upward

of

entire display page with top-of-page

if

cursorison

bottom

to

line.

internal switch set

upper

toptobottom

left

of

Word Structure

Total

word lengthisswitch selectable to9,10

bits consistingofthe following:

7-bit

data

word

or

8th bit - parity, odd

OR forced

OR 8th bit suppressed

PHYSICAL AND ELECTRICAL Dimensions

13.5 in. high x 15.5 in. wide x19in. deep

1-2

toIor

even

°

or

II

I start bit J

I

or

2 stop bits

Weight

25

pounds

50Hzor60Hz, switch selectable Optional

230 Vac

Power Consumption

60 watts @115 Vac

MONITOR

Input (Necessary Accessory - Available) Connector Printed circuit board card edge connector - Viking No. 2VK10S/1-2

Pulse Rate or Width Pulse Width:

Amplitude

ELECTRICAL SPECIFICATI,ONS

10%

TABLE 1-1.

or Amphenol No, 225-21031-101

100 nsec min.

Low

MONITOR

Video

= Zero

~g:6

INPUT

volts

Operating Environment

5 - 55°C without

DATA

Pulse Rate: 47 to 63 pulses/sec

(41

- 122°F), 5 - 95% relative humidity

condensation.

SPECIFICATIONS

Vertical

Drive

Signal Signal

Pulse Rate: 15,000

to 16,500 pulses/sec

Horizontal

Drive

Signal Rise and Fall Times (10%

to

90% amplitude

DATA DISPLAY Input Impedance

SPECIFICATIONS

(a) Video Input: (b) Vertical Drive Input: (c) Horizontal Drive Input:

Video Amplifier

(a) Bandwidth: (b) Rise

and

Fall Times

(10% to 90% amplitude):

(c) Storage Time:

High

= 4 ± 1.5 volts

Less than 20 nsec

Less than 100 nsec

Minimum

Shunt

Resistance

3.3 K

ohms

3.3 K

ohms

470

ohms

12

MHz

(-3

dB)

than35nsec

Less (linear mode) 315 nsec,

maximum

Less than

Maximum

Shunt

Capacitance

40 40 40

(linear mode)

pF pF pF

50

nsec

Retrace and Delay Times

(a) Vertical: (b) Horizontal:

900 sec retrace, 7 sec retrace plus 4 sec delay,

1-3

maximum

TABLE

1-2. CRT DISPLAY SPECIFICATIONS

Nominal Diagonal

Measurement

(inches) Phosphor

12

*Resolution is measured in accordance with EIA RS-375 except Burst

100 percent.

Geometric

Distortion

The perimeterofa full fieldofcharacters shall

P4

approachanideal rectangletowithin 1.5%ofthe rectangle

height.

Power

Requirements

Input

Connector

Receptable, Molex No. 03-06-1041 Supplied with Unit Mating Plug, Molex No. 03-06-2041 Necessary Accessory (Available)

Input

Voltage

Input

Power

Output

Voltages

ENVIRONMENTAL

SPECIFICATIONS

105Vto 24W (Nominal)

+

15VDC

+

12

*Resolution (TV Lines)

Center Corner

900 at 40 fL 800 at 40 fL

Modulation

(or

DepthofModulation) is adjusted

130

V rms (120 V nominal);

50/60

(short circuit protected)

kV DC; 12.6 V rms

for

Hz

Temperature

(ChassisorCustom

Operating Range:

Storage Range:

Humidity

5to95

per cent (Noncondensing)

Altitude

Operating Range:

HUMAN

FACTORS

SPECIFICATIONS

X-Ray Radiation

These units comply with

DHEW

Unit)

Rules-42-CFR-Part

5°Cto55°C Ambient

-40°Cto

Up to 10,000 feet

78

1-4

65° C

2.1

GENERAL

SECTION 2

INSTALLATION

This section contains

the

ADM-3A instructions ADM-3A, setting internal switches, connecting cables, turning-on power.

2.2 VISUAL INSPECTION

It

is

recommeded carton should

Carefully inspect damage undergone stringent quality inspections operational in perfect operating condition.

If

immediately. Save the damaged shipping as evidence for inspection by the carrier.

Only the consignee may register a claim with the

carrier for damage during shipment. However, Lear

Siegler

customer

2.3 INSTALLATION

The of

and

you

the unit is damaged, notify the carrier

Data

ADM-3Aisdesignedtooperate in a wide range

environmental conditions:

5-55°C (41-122°F), 5-95% relative humidity without condensation.

and

installing it in a suitable environment,

all packing materialstoprevent

wishtotransportorship the terminal.

during shipping. The terminal has

tests

Products

should such action be necessary.

informationtoaid in installing preparing information

that

yousave the originalshipping

your

priortoshipping; it left the factory

it for use. Included

for inspecting the

ADM-3A

will

cooperate

are

and

damage

for signs

container

fully with the

of

and

to

The unit is designed any

other

suitable hard, flat surface.

In cold climates, care should be exercised to

allow the

to

equalize with removing the unit from the shipping carton; this will prevent moisture from condensing warm soft surface, such as carpeting, which would obstruct the flow

through could result in overheating to

the unit.

2.4 SETTING INTERNAL SWITCHES

Twelve slide switches located inside the caseonthe printed circuit logic boar-d are used to select various terminal operating characteristics. These switches are set shipping parameters specified by the the terminal. Only the parameters listed Ordering have been selected switch setting changes should be made before attemptingtooperate the terminal. Locationsofthe internal switches

Form

on

air. Avoid operating the unit on a

the

checkout

packed inside the shipping

sitona tableordesk top,

CAUTION

temperatureofthe terminal

room

temperature

a cold terminalexposed

of

cooling

bottomofthe chassis. This

at

the factory

according

customer

at

the factory. Any required

are

shown in Figure 2-1.

before

air

and

damage

ADM-3A

during

to

operating

when ordering

to

up

pre-

on

carton

or

the

,----------------------

I

I I

I I I

-

--

-- --

---------

INTERNAL

Figure 2-1.

SWITCHES

ADM-3A

-------,

FRONT

Internal

2-1

PANEL

Switches

SWITCHES

and

Controls

WARNING

Always

from

ADM-3A

disconnect

the

power

source before

case

to

the

access

ac

power

opening

any

component.

Switch functions

are

described below:

SPACE - ADV

In

SPACE Pressing AL

WAYS

with a space code

In

ADV

between a

the cursor ma

not

overwrite display

position, selects destructive cursor.

the

space

bar

or

receiving a space

overwrites

the

display

and

advances the cursor.

memory

position, selects non-destructive

Return

and

subsequent

1 be advanced but a space code does

y

memory

Line

locations. codeisdestructive between a Line Feed Return.

UC

DISP -

In

UC

DISP characters such

but lower caseisnot the

switch

In

UIL

lower case with the

U/L

DISP

position, allows displayofupper

only.

Lower

are

convertedtoupper

case codes

case

installedorifitisnottobe utilized,

must

stay in

DrSp

position, allov/s displayofupper

characters

UpperILower

the

UC

DISP

if the

terminalisequipped

Case option.

are

cord

the

internal

code

location

cursor

Feed

only;

The

space

and

the

transmitted

for

display.

position.

as

and

On

terminals with

switch

must

CURSOR

In

the

ON

reverse

block

be settothe12LINE

CONTROL

position, this switch selects a moveable

cursor

standard

12

which accesses

line display this

position.

any

areaonthe

screen. In

the

OFF

position, this switchselects the double-underline entered

Upward

occur

the

from

the

scrolling

when a full lineofdata

bottom

line in either mode.

cursor.

In

this mode,

bottomofthe screen.

and

top-of-the-page overflow

has

been entered

standard

data

from

is

LOCAL - OFF

103 - OFF 202 - OFF

These three switches operation

for

one

interfacingtothe

are

usedtoselect

of

the following

computer:

(1)

methods

without

ADM-3A

of

modems

(direct, local connection), (2) with 103-type

If

modems,

appropriate

the

connection

must Setting

to Send)

or

(3) with 202-type modems. The

switch is set (left position)

method

be settothe

the

LOCAL

to

rise

OFF

used; the

positions.

other

switch causes line

and

fall with each

according two switches

C.A

ll

(Request

character

to

transmitted.

DISABLE -

In

DISABLE

KB

LOCK

position, prevents locking

keyboard. In

KB

LOCK

position, allows electrically disabled (locked) by codes.

DISABLE - CLEAR SCREEN

In

DISABLE

displayed

position, prevents clearing

information

except

repetitive line feeds. In

CLEAR clear code

(CTRL

SCREEN

ADM-3A

screen by

Z).

position, allows

transmittingacontrol

50Hz - 60 Hz

Selects

set

50Hzor60Hz

to

correspond

display refresh rate;

with

input

power

12 LINE - 24 LINE

If

terminalisequipped

this switch

may

with 24-line display

be used

to

seiect i2

display.

keyboard

remote

by

executing

computer

frequency.

or

to

control

must

option,

24

iine

be

to

be

of

Setting the

Setting the 202 switch enables 202-type using the change channel

With all three switches off,

103

switch holds

secondary

the

directionofdata

channelorturnaround

over the

(half-duplex operation).

CAisheld low all the

CA

high,ifrequired.

primary

operation

code

to

data

time.

CODE

- SEC CHAN

This switch is active only with the 202 switch (described above) in the select the operation

In

SEC using is

summarizedinthe

The by a data EXTorEaT,

methodofline

with 202-type modems.

CHAN

the

secondary

CODE

turnaround

channel.

position, enables line

position

code The as selected by the switches described

on

turnaround

channel. 202

backofthis

allows line

transmitted

turnaround

position.Itis

for

half-duplex

turn-around

modem

handbook.

turnaround

over

the

code

may

used

operation

control

primary

be either

to

below.

I""v-r I:.J\

I-vrr

,...~~

EOT-OFF

2-2

One

of

these two switchesissettothe

position

to

select the line primary channel (See

CODE-SEC

202

and

CODE

beonand

selected, oneofthese switches

the

other

selected,or202 off,

must be set to the

operation

CHAN

off; with 202

both

the

OFF

positions.

turnaround

with 202-type modems.

switch description.) With

and

ETX

and

SEC

EOT

on

(left)

code for

must

CHAN

switches

2.5 SETTING FRONT PANEL SWITCHES

Twenty slide switches for selecting the

primary terminal operating characteristics are accessible from the case

ADM-3A

or

removing power to the unit.Togain access

front

panel without opening the

to these switches, remove the screw securing the identification plate and remove the10plate. The switches are

on

the left sideofthe

keyboard

shown

in

Figure 2-2.

In

BIT

8-0 position, bit 8isforcedtoa zero value

all

transmitted

In

the I position, bit 8isforcedtoa

PARITY

In

PARITY

bit

data

wordisa

In

INH (parity inhibited). will be

the

characters.

-INH

position,

(first)

the

bit following

parity no

The

stop

bit (parity enabled).

parity bit will be generated

bit following

bit.

STOP - 1 - 2

In

STOP-I

In the 2 position,

position, one

two

stop

bits

one

value.

the

7 -or8 -

the

data

bitisgenerated.

are

generated.

on

word

BIT 8-0

PARITVSTOP

I'lATA

- J

PAR-ODD

l C £

AUTO

RS

1I0X

19200

9600

4BOO

:;

2400

...

:;

18011

1200

..,

....

I

Figure 2-2.

- I

II

•

III Off

232

600

300

ISO

ilO

15

It

3

Q

W

A

S

Z

X

ADM-3A

I

IHH

2

e

[

VEil

UC

Cl

fOX

E R

D

C

DATA - 7 - 8

In

OAT

A-7 position, 7-bit

data

word

length

is

selected.

data

word

In the 8 position, 8-bit (The 8-bit

word

consistsofthe

lengthisselected.

standard

7-bit

data word plusan8th bit forcedtooneorzero according to the setting

of

the

BIT

8-0 - I switch.)

PARITY-ODD - EVEN

This switch has effect only with INH

switch in the

PARITY-ODD

CONTRAST CONTROL

~

!,

y

F

G

V

N

M

8

p

0

K

"

In In

EVEN

LC EN -

position, selects even parity.

UC

In LC EN position, the operational lower case

allowing

alphabetic

In UC position, only

PARITY

position, selects

generationofboth

character

upper characters will be generated regardless not

the

Front

Panel Switches

remains

SHIFT

operational

keyisheld down.

for all

the

PARITY

position.

odd

parity.

SHIFT

key

upper

codes.

case alphabetic

whether

The

SHIFT

non-alphabetic

is

keys.

-

fully

and

or

key

It

is

recommended these switches before first time. Switch functions

BIT

8-0-1

that

you check the positions

operating

the terminal

are

described below:

This switch has effect only with the switch in the 8 position.

OAT

for

A-7-8

of

the

AUTO

In

AUTO

position will

to the first position

previously upward the

NL - OFF

NL

position, typing in

automatically

on

the

bottom

one line.

The

new line.

the

80th

cause the

of

the next line.Ifthe

cursortomove

line, the display will scroll

operator

continues typing

character

cursor

was

on

In

OFF

position, the

is

disabled. Continued typingatthe 80th character position transmits each new character the 80th character

RS232 - CL

In

RS-232 position, selects RS-232C communi-

at

cations connector

In

CL

the

on

the rear panel.

position, selects 20m A current loop

communications

automatic

on

the display.

MODEM

at

the

New Line function

and

changes

(computer) interface

MODEM

interface

connector.

HDX-FOX

In

HDX

Characters typed are transmitted and automatically echoed back from the display.

position, selects half duplex operation.

ADM-3A

110 Channel for

top

of

the case. (See Figure 2-1.) Background intensity terminal

is

readjustment

adjusted

at

the factory before the

shipped and should

priortousing the terminal.

not

require

In

FDX

position, selects full duplex operation. Characters typed are displayed only if echoed back by the

computerormodem.

Communication Rate Switches

19200

9600

B These switches are used to select

4800

A the U

2400 1800

O puter and auxiliary device.

send/receive

communications

rate for

with the com-

data

1200

600

R Setting one switch to A hand (BAUD RATE)

300 150

T selects the associated rate.

the left-

position

110

EI

75

NOTE

Only one selected (left position)

2.6 SETTING DISPLAY

BAUD

RATE

switch may be

at

a time.

CONTROLS

Figure 2-3. Background Intensity

Because

(located in

the

topofcase)

WARNING

Background

control must be adjusted with the

3A case open with power on, it should be adjusted only by qualified service personnel.

ON/OFF

The power

Switch

ONIOFF

switchislocatedonthe

3A rear panel.

2.7

CONNECTING

ON POWER

a.

With the

position, plug the

proper

the

CABLES AND

ONIOFF

ADM-3A

AC

power outlet.

switch in the

Control

Intensity

ADM-

TURNING

OFF

power cord into

Contrast

The

Contrast

keyboard

operatortoadjust brightnessofthe characters

the

optimum

for turned

clockwisetoincrease character brightness,

counterclockwise

Background intensity

controlislocatedtothe rightofthe

on

the

ADM-3A

readability. The

to

front panel.Itis

Contrast

decrease brightness.

used by

knob

A Background Intensity potentiometerislocated inside the

ADM-3A

caseonthe circuit

board

in the

b. Connect the interface cable from the

or

modem

connector

c.

Connect the interface cable from the auxiliary

is

device (if present in your system) EXTENSION ADM-3A

d. Check the settings

verify

that

operation in

to

the

on

the

ADM-3A

interface connector

rear panel.

of

all front panel switches

the

terminalisset

your

system. Ivlakt; switl;h setting

MODEM

rear panel.

up

for

computer

interface

to

the

on

the

to

proper

changes if necessary.

2-4

e.

Set the ON /

position.

f.

Allow approximately20seconds for the unit

warm up.

OFF

power switch to the

• If the cursor control mode has been

selected, a reverse block cursor should appear

• If the cursoe control mode

underline cursor should bottom

• If the cursor does

contrast control proper

in the

upper

left cornerofthe screen.

leftofthe screen.

not

on

intensity.

is

appear

appear, adjust the

the front panel for

OFF

near

ON

to

an

the

NOTE

If the Full-Duplex mode

at

typing characters unless echo-back

by the

duplex

only if clear-to-send

disconnected.

the keyboard will not display

computer

is

selected,

or

modem. If half-

data

will be displayed

is

presentorcable

is

selected,

is

provided

is

2-5

3.1

GENERAL

SECTION 3

OPERATION

This section contains information for using the

ADM-3A

keyboard facilities, and for programming control functions The keyboard allows the transmit to the

128

all

3.2 DISPLAYING CHARACTERS

In the

USASCII character codes.

standard

computer

operator (and/orauxiliary device)

ADM-3A,

and

instructions

at

the computer.

to generate and

64

characters are displayed on the screen (upper case alphabet, numbers

most symbols

and

punctuation).

and

When a non-displayable lower case character

typed, the

proper

lower case codeistransmitted

but

the characterisdisplayed as upper case.

If

your terminal contains the

95

Display feature,

characters will be displayed

(upper and lower case alphabet, numbers

and

punctuation

symbols).

NOTE

Upper/Lower

and

Case

all

Typingatthe keyboard always generates codes which are transmitted; however, in

to

order for characters

be displayed control codes to affect the display the codes must be echoed back the

ADM-3A

display memory control logic, either by the (FDX)

or

the

ADM-3A

I/O

and

ADM-3A

to

and

computer

Channel

(HDX). All display actions described in the key

that

descriptions

follow assume the

generated codes are echoed.

If

the front panel

AD

V position, the space codeisnon-destructive after typing the or

computer

can space over

SPACE-ADV

RETURN

switchisin the

key;

that

is, the

operator

dataonthe line without overwriting each character with a space. The space bar

remains non-destructive following a

function until a LINE

LINE FEED Key

FEED

codeisgenerated.

RETURN

A codeisgenerated by this key which causes the

to

cursor on upward one line.

is

cursor to the first character position

SHIFT Keys

Eitherofthe two typing alphabetic characters shown in the upper portion

move downward one line.Ifthecursorwas

the

bottom

line, the entire display will scroll

LINE

FEED

does

not

of

SHIFT

another

Setting the

key to generate

"LC

the front panel

keysisheld down while

or

to generate the character

of

a typed key.

NOTE

EN - UC" switch

ID

plate

to

return the

the new line.

upper

case

under

the UC position causes upper case alphabetic characters without the SHIFT

key remains operational for all

be generated with

SHIFT

key depressed. The

or

to

non-alphabetic keys.

RUB (Rubout) Key

When typed while holding down the

transmits a non-displayable

Rubout

SHIFT

key

code (ASCII DEL)tothe computer. The cursorisnot advanced and

the character code stored in the

ADM-3A

display memoryisnot overwritten.

3.3 SPECIAL

FUNCTION

KEYS

In additiontothe displayable character keys, the ADM-3A keys for various terminal functions. Use

RETURN Key

keyboard contains a

and

of

these keysisdescribed below;

number

of

system control

other

A codeisgenerated by this key which moves the

of

cursor to the first character position

the line.

The

Rubout

computer

functionisnormally usedtotell the

that

a previous character should be

deleted. The lower case RUB key transmits/displays

underline.

REPT (Repeat) Key

When held down while pressing a character key,

at

repeats the character the terminalisoperatingata

a rateof12.5 per second.

baud

rate permit 12.5 cps transmission, the repeat rate reducedtothe transmission rate.)

3-1

that

will

an

(If

not

is

Space Bar

The

Space

key. Causes

and blank exceptions

Bar

is'

consideredadisplayable

the

ASCII

storedinthe

spacetoappearonthe

see

code

ADM-3A

RETURN

CTRL (Control) Key

When

held

down

while

the

code

patternofthe

to

oneofthe

Code

chart.

The

ADM-3A possible haveafunction in

Table

two

ASCII

3-1.

control

is

capable

codes,

within

foraspacetobe

display

screen.

Key).

typing

typed

the

another

key.

code

columnsinthe

of

although

machine.

The

generating

only

character

transmitted

memory

(For

key,

codeisforced

These

the

modifies

14

of

are

and

ASCII

all 32

only

them

listed

column-code sequence.Inany codetobe

CLEAR

a

Typing SHIFT

function

SCREEN

(SPACE

mde,

transmittedtothe

Key

the

CLEAR

key clears

may

-

the

be

disabledbythe

DISABLE

through0)to

causes

key while

entire

the

computer.

screentospaces. (This

Switch.)

complete

ASClI

holding

internal

ESCape

down

CLEAR

the

HERE IS Key

If

your

terminalisequipped

Answer

identification

special

the

In

capability,

Back

memory)toidentify

computer

terminals \\lithout

this key

feature,

message

that

typing (storedinthe

a message istofollow.

hasnofunction.

with

this key

your

terminal

iA,-utomatic

the

Automatic

transmits

ADM-3A

and

alert

i~ns,ver

Back

an

in a

Backspace (CTRL/H).

typed

while

holding moves the

transmittedtothe in

Bell

ADM-3A

non-destructively

left.

The

conjunction

(CTRL/G)

and

CTRL/

computer.

with

Sounds

transmits

down

the

Each

time

theHkey

the

CTRL

one

character

H

backspace

CTRL/Hmaybeused

Repeat

the

CTRL/

key.

audible

key,

position

beepinthe

G bell

the

UPLINE (CTRL/K)

When reverse-block

Return (CTRL/M).

RETURN

Line Feed (CTRL/J).

the

in

LINE

the

Cursor

cursortomove

key.

FEED

key.

Control

Duplicates

Mode,

upward

the

functionofthe

the

causes

one

function

Lock Keyboard (CTRL/O). Electrically

(disables) further unlocked clearing power

FORWARD SPACE

When reverse

HOME

When reverse cornerofthe

the

ADM-3A

keyboard

byacontrol

the

off,

thenonagain.

in

the

block

activities.

screen

with

Cursor

cursortoadvance.

CURSOR (RS)

in

the

Cursor

block

cursor

screen.

keyboard,

The

code

from

the

CLR

(CTRL/M)

Control

to

return

preventing

keyboard

the

keyorby

Mode,

to

the

computer,

causes

upper

ESCAPE KEY (ESC)

When cursor character,arow

in

Cursor

sequence.

Control

ESC

code

(SPACE

must

Mode,

be

followed

through7)and

initiatesaload-

cursor

code

code.

line.

locks

can

turning

by

an

to

the

of

any

be

the

the left

is

BREAK

This key

function,

message.

Key

activates

normally

the

standard

usedtointerrupt

teletypewriter

an

incoming

Break

NOTE

The

Break the the cause your

BREAK

key

down

the

terminal.

functionissustainedaslong

keyisheld

foranextended

computer

down.

to

disconnect

period

as

Holding

may

from

3.4 PROGRAMMING & WORD STRUCTURE

The

=

a

computertowhich

has

full

control

functions

keyboard,

be

executed

The ting character codes

3.4.1

The

control

Backspace

non-destructively left.

which

plus a few

computer

the

appropriate codes

will be

are

from

controls

will be

recognized

Remote Control Functions

remote

computer

functions:

BS

Bell BEL (CTRL/G).

the

ADM-3A.

Return CR (CTRL/M)

destruciively present

to

line.

the

over

the

possible

additional

the

computer.

the ASCII displayed,

and

can

(CTRL/H).

one

character

Sounds

the

first

ADr-.1-3,A.isinterfaced

terminal.

from

functions,

ADM-3A

codes.

acted

perform

Moves

the

Moves

character

All

control

the

ADM-3A

can

by

transmit-

Displayable

and

valid

control

upon.

the

following

the

cursor

positiontothe

audible

the

positionofthe

beep

cursor

also

in

non-

3-2

Line Feed

IF

(CTRl/J).

Causes the entire display to move upward one line, leaving the cursor positioned in the same

character

position

on the next new line.

Upline (VT) - Moves cursor up vertically when

Cursor

in

Forward Space (FF) - Moves

when in

lock

locks the

Control Mode.

Cursor

Control

Keyboard

ADM-3A

cursor

Mode.

SI

(CTRl/O).

Electrically

keyboard, disabling all

forward

keyboard functions.

Unlock Keyboard SO

ADM-3A

keyboard, restoring all keyboard

(CTRl/N).

Unlocks the

functions.

Clear Screen SUB

character memory (This function

positions in the

and

clears the screentoblank

may

(DISABLE-CLEAR

Home Cursor (HOME) - Causes the

returntothe in the

load

Cursor (ESC =YX) - This

Cursor

upper

Control

sequence causes the row

and

X respectively.

column

defined bythe

The Reference Tables

(CTRl/Z).

ADM-3A

Clears all

display

spaces.

be disabled by

SCREEN

the

internal

switch.)

cursor

left

cornerofthe screen, when

Mode.

four-character

cursortobe positionedtothe

3-1

and

ASCII

3-2ofthis

values

manual

of

to

show the actual binary codes generated by the

ADM-3A

and

used for

computer

controlofthe

terminal.

Y

Table 3-1.

ASCII

Code Mnemonic Function ADM-3A

CTRL/@ CTRL/A CTRL/B CTRL/C

CTRL/D

CTRL/E ENQ CTRL/F

CTRL/G BEL CTRL/H BS CTRL/I HT CTRL/J CTRL/K CTRL/L CTRL/M CTRL/N CTRL/O CTRL/P CTRL/Q CTRL/R CTRL/S CTRL/T CTRL/V CTRL/V CTRL/W CTRL/X CTRL/Y CTRL/Z CTRL/[ CTRL/x CTRL/] CTRL/A

NUL SOH STX ETX

EaT

ACK

LF VT FF CR SO SI

OLE OC1 OC2 OC3

DC4 NAK SYN

ETB CAN

EM

SUB

ESC

FS

GS

RS

AD

M-3A Control Codes

as

Available

modem operation

Availableassecondary channel line

modem operation

Initiates

option*

Sounds audible beep in Backspace

Line Feed Upline Forward Space Return Unlock Lock

Keyboard*

Clear Screen Initiate Load Cursor

Home

secondary channel line

10 message in

Keyboard*

Cursor

terminals

AOM-3A

with

turnaround turnaround

automatic

code

for

code

for

"Answer

202 202

Back"

*Executable

only

from

computer.

3-3

Table 3-2 USASCII Character Codes

GRAPHIC CHARACTER

CONTROL SET

BITS BITS 4321

765

0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011

......

f"\f"\

IIUU

0 000

NUL

SOH STX

ETX

EOT

ENQ ACK

BEEP

BS HT LF VT

........

rr

1 001 OLE DC1 DC2 DC3 DC4 NAK

SYN

ETB

CAN

EM SUB ESC

....

t'"'

rv

2 010 SP

!

"

# 3

$

0/0

&

( 8 ) 9

*

+

,

3 011

1 A 2 B

4 100

@

5 6

101 P

Q

R

C S

4 0 T d

5 E 6 7 G W

F V

U

H X

Y i

Z j

[

\

,/

...........

I

J

K

I \ I

L

110

a

b

c s

e

f v

9

h x

k

I

7

111

P

q

r

t

u

w

Y

z

{

1101 1110 1111

""

CR SO SI

GS RS US

.........

Control

Codes

(Generated by holding key

the

key shown in

CTRL

while

typing

corresponding

col-

umns 4 and 5.)

3.4.2 Data Character Format

The

ADM-3A

America

change).

many

ADM-3A

the

f_l

..

n

_n_;"'u

\PiU",

peu

USASCIIisa 7-bit code. But because

of

the computers

iLy

uses

Standard

USASCII

Code for Information Inter-

and

(United States

other

devices to which

may be interfaced use 8-bit words

"'_

.,,;

...

\.."'

.....

Vi"'lLUVUL

_n_;"'u\

peu

"'\"0

iLyhLa,,-

i\

nl\.,f'2i\

rl.L'

",++0_"

U.L

-.)rl.

Vii"-i"

a wide choiceofword formats selectable by the user.

of

,,,

-

=

>

/

? 0

Displayable in

standard

~

M N

ADM-3A

]

f\

+

m

}

,......

n

DEL

0

,

...

T

I

Displayable with

ADM-3A Upper/Lower Case Display feature.

3-4

The

data

character may be 8 bits in length, plus

without

the optional parity bit.Inthe caseof8-bit characters, bit 8 by the user.

is

always forcedto1or0as selected

or

DATA

(7 OR 8 BITS)

PLUS

OR

WIO

PARITY

OR

DATA(7OR8BITS) PLUS OR

WIO

PARITY

3.4.3 Data Transmission Format

The

ADM-3A

This means each

uses

asynchronous

transmission.

characteristransmitted as a complete, self-contained message consisting data

character withorwithout

start

bit

and

followed by

parity, preceded by a

oneortwo stop bits.

of

the

When the

start

bitisreceived, a clock signal initiatedtoclock in the remainderofthe word. The one

or

two stop bits are usedtosignify the endofthe

word

and

terminate the receive clock.

Generally, transmission rates use two stop bits, stop

bit.

The

ADM-3A

and

control

ratesof150

codes

set are shown in tables

3-1

of

110

baud

and

higher use one

and

the USASCII code

and

3-2, respectively.

and

lower

is

3-5

4.1

GENERAL

SECTION

4

THEORY OF OPERATION

4.2.2 Display Refresh Operation

This section describes the ADM-3A first described with reference to diagram, and then each element shown in the block diagram illustrations and to logic diagrams contained in Section 6

4.2 GENERAL

The general organizationoflogic in shown in figure 4-1. This figure divides logic into functional blocks and shows the relationships between blocks. sheet block

4.2.1 Display Generation

Signals maintained counters (display counter logic).

The first counter (the pulses from timing signal in the ADM-3A. The purpose dot sequential address the presettingofthe video serializer. Each increment of

the counter defines the positionofa single any line (dot row) Any character (figure 4-2). A character position and nine dots high characters

A single horizontal sweep produces all dots in a given characters in the character row. The character counterisincrementedfor every seventh dot column to define the position At the end

incremented

The character row counter ninth dot line to define the position

character row.

The four display counter outputs control memory addressing, character generation, and many functionsofADM-3A

performs its different functions. Logic

is

described with reference to specific

of

this manual (Drawings).

FUNCTIONAL

of

the logic diagram

is

detailed.

that

cause a display to be generated and

on

the screen arefurnished by a string

an

oscillator. This clockisthe primary

counteristo

both

of

and

time the presentation

to

of

any character in the display.

is

made upofa 5 x 7

to

provide 2-dot spacing between

horizontally and vertically.

of

each

dot

the next

manner

It

on

dot

counter)isclocked by

the character generator

of

each character in the row.

row, the line

dot

rowisscanned out.

is

incremented by every

logic.

in which the

an

overall block

DESCRIPTION

ADM-3A

AD

also indicates the

which logic in any

of

arrayofdots

is

seven dots wide

the

CRT

dot

row for all

counter

of

the next

M-3A

of

the the

and

dot

beam

dot

other

of

in

is

Except when received

is

contents data) are continuously presented Memory address logic requires only sequential character out

Each character read from the refresh memory stored for presentation to the memory (and test operation).

The USASCII-coded character and produces a five-bit output row.

for each

The count row.

4.2.3 Monitor Video and Drive Circuits

The 5-bit character generatorispresented to the video circuits as a serial except during position sweep drive signals, with horizontal drive triggered by the triggered when the character row (standard)or24 (optional).

4.2.4 Receiving and Storing Data

Data 3A line. Baud rates are derived from the LSB count, clock may be the same rate option).

Received which memory address, during loading, summing the which represents the true position the screen, represents the display has scrolled. The virtual address which thus derived corresponds to the refresh address for that

of

the refresh memory (an entire "page"

and

row counts (CCn and RCn)toread

the memory contentstothe storage latches.

to

data

ROM

to

data

character generation decodes the stored

specifying dotstobe displayed for each

That

is, the characterispresentedtothe

dot

row as the character rowisgenerated.

CCn

selects the

dot

row

CRT

and

row counts are usedtogenerate

startofeach

transmission rates are selected in the

match those devices on the other endofthe

DC1.The receive clock and the transmit

dataisclocked into the refresh memory,

is

addressed by memory address logic. The

Cursor

and

the Offset

numberoflines (since Reset)

row. The Refresh Addressisdetermined

dataisbeing loaded, the

of

on

the screen.

ROM

transmitterlogicfor read-back

dot

pattern

data

read from the

data

stream, continuous

retrace periods.

dot

row,

and

count

or

different rates (split

Row Position

of

Count

character

dot

ROMs

for each

Character

vertical drive

reaches

is

formed by

Count

the cursor

(OCn), which

ROM

monitor

CRT

AD

of

the

baud

(CRn)

that

dot

M-

dot

on

the

12

is

4-1

+:>.

I

tv

TO/FROM MODEM

OR

COMPUTER

RECV

DATA

LINE CONTROL

SERIAL DATA lOOP

DATA RECEIVER LOGIC

&

COMMAND

DECODERS

INTERFACE CONTROL LOGIC

(12)

DATA TRANSMITTER lOGIC

(10)

DATAn

DECODED COMMANDS

{

(6)

~

----0-~-----.-----.----'

+---0)--------------.--------1

KCn CBUFn

RCV

ClK

....-.....-----+-1

REFRESH

MEMORY

ADDFIESS

lOGIC

(5)

(9.10)

lATCHES

(8)

CURSOR lOGIC

(7)

(n)

on

indicates

which

OSCILLATOR

sheetoflogic

the

logic

appears

DOT CHARACTER

DOT CHAR

diagram

VIDEO

COUNT/CHAR

POSITION

ROW

COUNT

ROW

COUNT

Figure 4-1. ADM-3A Interactive Display Terminal,

Functional

Block Diagram

by

another

Row Received commands are decoded and used

control

Feed, Backspace, Carriage Return,

functions.

4.2.5 Cursor Generation

The cursor marks the position which the next character will appear. When the Cursor will be entered in the cause the display to roll upward. The cursor formed by displaying five dots in the eighth ninth rests. logic alongwith character bits read from the ROMs.

When the reverse block cursor the reverse image cursor currently resides.

The cursor position code WCn refresh memory in read-back test operation.

circuit which sums the current Display

Count

dot Cursor

(RCn) and the Offset

ADM-3A

Control

rowsofthe character position in which it

Cursor

logic.

Commands

switchisin the

bottom

informationisORed

Controlisin the

is

a 7 x 9

of

the character

Count

include Line

on

the display in

OFF

position,

row: Line Feed will

into video

0N

position, the

dot

figure containing

upon

is

used to address the

(OCn).

and

other

data

and

output

which the

to

4.2.6 Keyboard Logic

, The keyboard

compose transmission. As a character operator, it appears (as KCn) logic, and (in half-duplex transmission) into the refresh memory for display. In full-duplex, communications characters originating board back from the

is

formatted

appearonthe display only if they are echoed

4.2.7 Data Transmitter Logic

Data

transmitter10gic receives characters generated

at

the keyboard answerback logic converts the seven-bit character into serial-bit form along with start, parity,

In read-back test operation, the contents memory buffer (CBUFn) may be accepted for transmission in the same lines.

and

associated logic are used

data

for

display

computerormodem.

(or

and

put

and

wordtothe modemorcomputer.

mannerasdata

and

simultaneous

is

typed by the

at

data

generated

on

KCn

stop bits, and sends the

transmitter

is

loaded

at

the key-

at

optional

lines) and

of

onthe KCn

to

the

DOT

COUNT

o 0

o 0 o 0 o 0

(DC)

0.0

0.00.

0.00

COUNT

•

~7

00

o 0 0 0 0

0

•••••

O.

••••

•••••

000

•

••

•

o 0 0

r79

o 0

•

••

•

o 0

f

I-

Z

::J

0

U

:i:u

o...J

cr-

I-

0

!

8

f

I-

z

::J

0

U

:i:u

O...J

cr-

I-

0

~

0

-

~

.....

•

1-

•

.000.0 .000.00.

•••••

•

l-

z

::J

0

u

:i:

0

cr crcr

w-

I-

U

«

cr

«

:I:

U

u

•

• •

•

•••••

•

• •

•

_I

11 OR 23

I

-

CHARACTER

•

••••

•

••••

I

POSITION

(CC)

Figure 4-2. CRT Display Monitor

4.2.8 Interface Control Logic

This logic Send the reverse-channel control the

other.

Switches common under

4.2.9

The 3A

is a commercial quality

The construction circuitsofthe

4.3

The logic diagram, performing

Refertoblock

controls

exchanges

ADM-3A.

Clear-to-Send

between

Either

system

from

one

endofthe

internal

CRT

adapt

type

display

solid-state

the

logic

103

or

202

control.

Display Monitor

monitor

unit

installations

video

reproduction

monitor

LOGIC

following

features

for

reliability

TV

monitor

DESCRIPTION

paragraphs

representedbyeach

figure 4-1, as well as logic

functions

and

not

timing

modemorcomputer

a

code-turnaround

may

communication

to

modems,orto

employedinthe

for

useinindustrial

where

are

printed

and

are

describe

blockinthe

indicatedinFigure

diagrams

and

Request-to-

be

used

to

interface

reliability

and

desired.

circuit

uniformity.

transistorized.

the

operation

overall

and

that

accompany

or

transfer

line

with

operate

ADM-

high-

board

block

circuits

and

to

the

and

All

of

4- i.

the

text,

as well astothe

Section6in

this

manual.

logic

diagram

included

in

4.3.1 General Clear Circuit

a

Circuits all when

shownonsheet7of

control

logicinthe

applied

power

ADM-3A

causes

the

logic

tobeinitialized

the

+5Vdcsupply

diagram

cause

to

rise.

As

the

supply retriggerable signal logic the

CLEAR,

through

signal

actionofthe

voltage

one-shot,

the

whichisdistributed

six

inverters.Incircuit

TESTER

INITIALIZE

one-shot.

reaches

one-shot

trigger

creates

board simulates

level

to

ADM-3A

of

the

reset

testing,

a

the

4.3.2 Display Counters

The

display positions character define and

the

the display. and

timingisshown

The

basic byasimple oscillator twice

the

dot

counters

and

dot

rows,

line,

and

character

positionofeach

position

Figure

clock

of

4-3 is a

is a

10.8864-MHz

video frequency.

counter.

provide

character

rows.

dotina

each

character

block

diagramofthis logic,

in figure 4-4.

circuit.

The

clock

a

count

position

These

character

in

signal

clock

frequency

(eLK)

of

dot

in a

counts

matrix,

the

total

generated

drives

is

SHEET 2

DC3

DCO -DC3

CCO-CC7

ICC80

LC3

LCO - LC3

RCO

- RC5

RC

RESET

Figure

4-3. Display

Counters,

4-4

Block

Diagram

CLOCK

n..n..n.IlJlJ1I

PERIOD-643.¢¢39

nsee,

FREQUENCY

= 1.5552

MHA

DC¢~

DOT

DC1~

COUNTER

DC2~

PERIOD

DC3 U 1

CC¢

CC1 CC2 CC3

CC4 CC5

CC6 CC7

LCCLK

1---------------------::::=:;::::~::::=~;:;;.77'"'T7""".7"'7""::.._r"7_J

CHAR

VIDEOSRLOAD

U

= 555.555Msee,

COUNTER

FREQUENCY=1.8¢¢KHZ

RETRACE

POSITION

COUNTER

PERIOD

= 61.7284Msee

FREQ=16.2¢<iHDKHZ

H-

DRIVE

LC¢ LC1

LC2 LC3

CHARACTER ROW

COUNTER.

51>

HZ

OPERATION

RC¢

RC1 RC2

RC3

I-----------------------J

RC4 RC5

t--------------------------------------.....J

6¢HZ

OPERATION

RC¢ RC1 RC2

RC3 RC4 RC5

(ALWAYS

LOW

DURING

6¢HZ

OPERATION)

6¢HZ

V-DRIVE

5I>HZ

J""L

LINE

COUNTER

(DOT

ROW

PERIOD-91.8577

V-DRIVE

COUNTER)

nsee,

--.n-

PERIOD

CLOCKED

PULSE

WIDTH

H-DRIVE CHAR

LAST

CLOCKED

RISE

24.434Msee

TIME

VIDEO

PERIOD

FREQ=5¢HZ

RISE

FREQ=6¢HZ

NOTE:

ONE AFTER

FREQUENCY=1¢.8854

~===~

EDGES

W/H-DRIVE

= 16.667msee,

W/H-DRIVE

STARTS

(643nsee)

=2¢ms

MHZ

Figure 4-4. Display Counter Timing

4-5

The

dot

counter comprising to

10 overflowat15, count, character position

The

eight-stage

the

positionofeach raster counter character

The

character

each

at

the

count

andisagain

DC3,

clocks successive addresses

ROMs,

counter.

character

line,

and

controls

providesatotal

position,

position 79, presetsto240, 255,

and

then

wrapstozero,

CC6

are

binary

That

is,

ee7

is

low

counted,

A flip-flop

and

high

produces

countofretrace

which a upon. character

The each

commandatthe

The

outputofthe

line

counter.

character

line

rowofcharacters.

counts

character.

of

the

The

zero,

presetatzero. Its final

and

triggers

position

characteronthe

horizontal

countof96 (80

and

16

count

counter

counts

counts,

through

but

CC7

while80character

during

time.

the

ICC80

retrace

signal

110 interface

LCCLK

counter

The

counts

counter

seven

dot

character

counts

through

the

counter

80-character

retrace

counts

for

the

counts

Outputs

from

the

CCO

overflow

has a valueof80.

positions

time.

ECC80

indicates

for

the

maybeacted

flip-flop clocks

the

lines

counts

columns

is preset

the

to

the

character

controls

time.

The

for

retrace).

zero

to at

through

are

the

first

time

at

the

that

form

module

nine. characters, through7.The row

The rows through power (60 EN) sets proper the

Counts

and

0

dot

last

and

rows

count,

8

form

are

formed

LC3, clocks

spaces between

counterata frequencyof1.8 KHz.

character

appearing

line,

time, resetting

counter

counts

verticallyonthe

vertical retrace time (six

and12counts

up

logictoproduce

character

row

for

a 50-Hz line). A switch

the

countertozerotobegin

count.

the24character

display,

counts

RCRESETatthe

by

the

character

and

for

counts

a 60-Hz

4.3.3 Row Counter & Offset Counter Logic

The

Row

Counter defines and entered counter

12-line

the

actual

consequently,

into

memory will be clearedtozeroon24-line, mode

operation,ora of

the

positionofthe

The

Offset addresses, virtual

during

(apparent

generatedbyscrolling operations.

(Figure

row

by clear

Counter

data

visual)

in which

the

row

will

appearonthe

a

power-up

screen

Cursor

relates

entry

row

4-5

and

Logic sheet

the

cursor

in which new

screen. This

clear, key-clear

command,

Control

irrespective

switch.

absolute

and

refresh,

addresses which

The

OC,

resides,

and

memory

to

like

1

3)

data

on

the are the

KEY CLR CC8G

LCO

ENX

LF

BO

FL

GATED

XCLK

ESC

DATA

VT

24

EN

24 EN

~

ccao

-

CR 23

BORROW

U

-

CLEAR LOGIC

t

r

~

-

DN

f--

-+

ROW CLR

CLROC

DN

CRO

LINE

OCLOD

--

R24/31

A

OFFSET COUNTER

ROW COUNTER

t

-

CR 23

J

OCO

- OC4

,

OFFSET LIMIT LOGIC

CRO-CR4

ROW LIMIT LOGIC

~

TO

MEMORY

ADDRESS

&

CURSOR PRESENTATION LOGIC

DISABLE

CLR SCRN

-

~

LR

C

RN

SC

0

BEL

I

-I

START

LOGIC

~I

I

START

t

LINE-FEED

SELECT

LOGIC

---

CLEAR2.3~

HOME-.

STARTCLR

~

I

i

LINE

3

DN

2

1,

1·

DATA

5

4

~

I

LOAD-ROW LOGIC

UPLINE LOGIC

t t

Figure 4-5. Row

Counter

& Offset

4-6

Counter

Logic, Block Diagram

RC,isinitially cleared by operations noted above, however, a sequence

initiated by the

to

codes

be written into each character cellofthe

START

current row duringfirst line-scan period. At the end

.will generate a line-feed signal,

will increment the OC. The process

OC

with the

pointing to the next rowofmemory

anyoneofthe clear-screen

is

then

logic, which causes space-

80

character-periodsofone

of

the line-scan, CC80

DNLINEA,

is

then

which

repeated;

addresses, which are also filled with space-codes.

24

After

switch

which terminatesthe the this point,

contain

12-line mode), and the true

such operations (12, if the 12/24 select

is

closed), the

OCLOD

START

signalisgenerated,

operation,

and

freezes

OCata countofzero (1, if in 12-line mode).

both

the

"minimum

Rowand

count" (zero in 24-line,

Offset counters will

and

virtual row-

addresses will be the same. (MS-A).

of

After completion Counter

will be disabled until the Row been advanced Cursor

Control switchisopen signals (DNLINEB) will be sent to the Row each CC80 time, until a

reached. At this point, the Row disabled until either the closedoranother

Counter

If

Counter operation,

Home the same

will be enabled.

the Cursor Control switchisclosed, the Row

will remainatminimum

and

will respond to any downline, upline,

and

absolute (load cursor) row directives. In

manner

a clear operation, the Offset

or

set

to23(bottom

(ENX

true), line-feed

count

of

23

Counter

Cursor

Clearisperformed,

Control

and

count

as when

Cursor

Controlisoff,

Counter row).Ifthe

Counter

has been

will be

switch

the Offset

after a clear

downline directives which occur when the Row

Counterisat23will be routedtothe Offset Counter,

to

causing it by adding a difference

increment, and scroll the entire display

of

one unit between the true

and virtual row addresses.

Whereas the Offset

Counter incremented (DNLINEA), the Row incremented, decremented, cleared an

absolute value (DNLINEB, VT,

LDROW).

In the event a value in excessof23

can only be Counter or

can be

loaded with

ROWCLR,

loaded, the counter will be cleared to minimum count. If the Row currently holds the minimum count,

Counterisdecremented when it

BORROW

will

occur, and the counter will be forced back to

minimum

count

generated if a

(ROWCLR).

HOME

ROWCLRisalso

(RS), directiveisreceived.

Both counters, when in 12-line mode, have the least

and

significant bit forced true,

all increment decrement directives will affect only the higher order

bits. In this mode, therefore, only odd virtual

that

addresses will be accessible. Note,

scrolling the display will still produce only odd addresses, since the Offset

Counter

will

count

in unitsoftwo, which

At

1in

has

or

when

"added"tothe odd

an

odd virtual address.

in

Row

Count

will still result

Figure 4-6 Shows the timing for the Clear Screen

or

Operation. The timing for Key Clear

is

clear operations that

in the latter two situations,

high without benefit

identicaltothat

STARTisforced

of

DOlT.

power-on

shown, except

4.3.4 Column Counter Logic

The

Column

and

its associated logic define the character-position

of

the cursor, irrespective mode. accommodate operations, associated multiplexor, with either values, as the last character

The

Counter

counter

both

(figure 4-8

is

and

logic sheet

of

the current cursor

bidirectional,

backspace and forespace

andiscapableofbeing loaded, via

of

two fixed

or

a variable position-code whichisobtained

of

the

four-part

Load

4)

to

an

Cursor

sequence.

Back-spacing (count-down)

or

local

remote backspace

is

affected only by a

command

(BKSP), while

forward-spacing may be accomplished by either a

is

character-entry, a forespace operation. All received characters will cause a forespace afterthe character except control characters

commandora

is

written into memory,

and

the three non-control characters which follow ESC during a Load sequence. commands CC80 time. forespace indicating, the initiation

The Column

For

both

character-entry and forespace

(FF), the

During

is

generated each time

counterisadvanced during

Read operations (test only), a

of

Counteriscleared in

XLOAD

character transmission.

anyoneoffour

'Read'

Cursor

occurs,

situations:

a. A Carriage

Return

received, either from the keyboard

(CR)

command

or

is

a

remote source.

b. A Home (RS)

is

c.

An underflow occurs, due to attempts to

back-space from column

commandisreceived.

O.

d. A start-sequenceisinitiated by oneofthe

power-up/ clear operations.

When the Column 80th column-count (code=79), generated, causing loaded into the

Counterisincremented past the

an

overflow signal

an

absolute

counter

at

count

the next

value to be

LCCLK

is

transition (CC81-time).Ifthe auto-new-line switch is

open, a

back to the last column position.

7910

code will be loaded, forcing the cursor

If

auto-newline

is closed, a zero-code will be loaded (carriage return) and

a line-feed enable signal (BOFLO) will be

4-7

DATA

RCVD

(U~

CLR

SCREEN CODE

I

_____

CLE,lI,R SCREEN

-.-J

----

+:0-

r

00

CC6 LCCLK

cCB<,'>

INPUT DOlT

DOlT

CLR

SCRN

START

ERASE F

LF1

OCLOD

U U

n

_________

ST

I_

CLR

SCREEN

DATA

BUFFER

_________

------~;:::::======--

:=:=

====-

===-=_-_-_-_l

OCl

=.=-

-=-

OC2

OC3

OC4

-=-_-_-

===:-=--=-==-l

=---=--==::::~I

DON'TCARE

_JL-

__

J

~

rL

--'n

1~1<ll

--1

-----f~

LJ

rL

--LJ

_IL-

I _ _ _ _ .

______

L

...

I--N-U-L-L-C-O_D-E-IN-----------------------------

I

DATA

BUFFER

l========

1

_ _ _ _ .

I

,-----

.

---Jr;:~o;~-

.J:.l~~

['=-1-

C'=-j

-

_1'=-]-

.

CLR

SCREEN

.-

WAITINGINUART

.....

:.--C-l-R-R-OW

~

- - -

-;~-_""J-

-1--=.J

-1::::

-

""L-_~

-----_._-------,

------.L

-

-C-l-R

-RO-W-2-3-~--.

- L _

J - -

------,L

_-i_-r

LJ

fL

CLR

SCREEN

COMPLETE

__

U U

n n

N_U_L_L_C_O_D_E_I_N DATA

__

BUFFER

_I

---J

~

----====::::=:~fl.-

"_I"

CLR

SCREEN

DATA

BUFFER

L _

...__C_l_R_RO_W_'_i---.J_...!.-__. _

L _ L _

IN

rL-

'--

_

1

L

_

NOTES:

TOTAL TWO

NO

(FOUR

OPERATION

CHARACTER

FILL

CHARACTERS

NULL

FILLERS

TIME

= 1,73

TIMES@96"u

REQUIRED

Il1sec

BAUD

@ 19.2 K

@

=

2.c>k

96c>li

Il1sec

BAUD

BAUD)

DISPLAY

-----.,...----:.R=Cl=RC4~

ROW

COUNTER

SUM SUM SUM SUM

lR, 2R, 3R, 4R.

CURSOR

ROW

COUNTER

OFFSET

COUNTER

ERASE F

DISPLAY CHARACTER

CURSOR

CHARACTERCTR

CTR

CC<1>-CC6

READ

DCO

RCO

CR1·CR4

OCl·0C4

DC""

CRO

SUM'"

SUM

lW.

SUM 2W. SUM

JW.L.---+----++l

SUM

4W MULTI-

SUM'i'W

POS6

P0S4. POS5

SELLINE

PLEXER

MULTI-

PLEXER

CHIPEN A

CHIPEN

MAS.MA9

MA4-MA7

MA<1>-MAJ

B

Figure 4-7. Memory Address Logic, Block Diagram

generated,

enable either the

Row

or

to

countertobe incremented.

When the code in the

the signal

LINE a received BEL-code, will cause the Beeper a tone, If

Load

Counter

the

Cursor

announcing

Control

sequenceisperformed, the

multiplexor will select the from the Received codeonthese lines will be

Column

Counter

reaches

ENDisgenerated. This signal, like

to

the

approachofthe end-of-line.

switchison

(ENX-true)

Column

DATA

Data

Buffer,

loaded

and

into

the

Column-

counter CC80 time. The two most significant bitsofthe (DA

TA6

and

DATA7)are modified in

ASCII are interpreted as In the event a is counter 0008

4.3.5

The

8)

character-cell in which the

codes space (040s)

translated

loaded, the

either

column

OVERFLOW

back

throughL/C codes

code

to I

17s

0008

greater

logic will force the

(Auto-Newline off)

(Auto-J\ewline on).

Cursor

cursor

Presentation

logic (see figure 4-8

Logic

and

performs the functionofdetecting the

cursor

order

"0"

through

than

1178

logic sheets 7 &

current

resides,

Offset

7110,

sound

and

lines

code

that

(1378)

1178.

(7910)

or

and

at

mixing videotoobtainarepresentation Cursor-mode three and the Counter,

a

coincidence occurs,anequality signal is

If

forced bottom to comparators

Display and an

If

flops will be enabled only the below the 24th position enabled detected coincidence signal two to synchronize the

the

coincidence signal with

the

character

determinedbythe

switch.

The

logic consists

of

comparators,apairofunit-delay flip-flops

video mixing circuits.

current

cursor

to

the Display

row, as definedbythe

One

Row

comparator

cursor

Count.

(ROWCOA)

generated. the

Cursor

true,

the

two

ROWCOGistrue

equality signal will be senttothe

the

Cursor

counters

Control

since the

line.Ifthe switchison,

column

relate the 7-bit

Column

switch is off, row-equality

cursor

will always resideonthe

ROWCOAisgated

comparators.

Count.

When

The

WC

counter

coincidence occurs,

two

codetothe

indicating row-coincidence,

delayflip-flops.

Control

are

the

flip-flops will always be enabled. In the

condition,

switchisoff,

scanning

row

of

during the data,

the period when

two likes immediately

whereas in the

the flip-flops will delay

the

delay flip-

character

cursor

with the displayed

a set

of

relates

Row

When

column

on

the

periods,

is

charactersonthe screen.

4-9

DATA DATA

1-

7

CTRL CHAR

ESC

READ

X

LOAD

XCLK

CC80A

DEL

ESC

BKSP

FORESPACE

1

2

~~

I

-

FF

-

FORESPACE CONTROL LOGIC

CARRIAGE

I

START

HOME

RETURN

LCCLK

I--

ESC

2

(UP)

(DOWN)

(CLR)

AUTO

11,

MUL

(SEL)

Il

OVERFLOW UNDERFLOW

LOGIC

NL

TIPLEXER

UP/DOWN COUNTER

+

f

BOFLO

TO

MEMORY

ADDRESS &

CURSOR

LOGIC

WC=8¢

WC

BORROW

r---LJ

WC¢-WC6

1

(LDI

OVERFLOW

&

CR.-CR4

RC¢-RC4

LC1, RC3, R DC3

~

VID

-

""

C4

EO

+

COMPARATOR

ENX

I

~

ROWCOA

~

CURSOR

SELECT

Coiumn Counter

C~-~7~

WC4-WC6

~

-----.

ROW COG

MODE

LOGIC

•

~

COMPARATOR

CURSOR

FLIPEN

CURSOR & VIDEO MIXER

I

~

C~CO~

WC¢-WC3

CURSOR TIMING

LOGIC

~

t

~

COMPARATOR

....-

I

~

-

VIDEO

Cursor Presentation

Figure 4-8. Logic Block Diagrams

4-10

With

Cursor required, since the ation

occurs

Control

during

off, no

double-underscore

the are being displayed. With cursor character-video

causing the the

coincidence signal

datainan

cursortoappear

character

in which

position

additional

mixing

represent-

period

whennocharacters

Cursor

Control

(CURSOR)isgated

exclusive-OR element,

as a reverse image

it resides.

on,

the

with

of

is

Each cause assume

subsequent a successively

the

top

scroll

higher

display-row position, with previously associated with "rolled"tothe

The

second five-bit

Cursor

bottom

Row

positionofthe

adder

Count

operation

will,

memory-row

that

position

producesasum

+ Offset

Count

therefore,

address

the

erased

display.

equal

+ I

to row and

to:

4.3.6 Memory Address Logic

The

logic

group

shown

5

performs

current

the

all the functions relatedtoreconciling

entry-row virtual row (Offset row-address

converting

in

the

visual 80-character by 24-row visual

formattoa 64 by 30 byte

is

task

accomplished by two five-bit

full adders, while

in figure 4-7

(Cursor

Counter)

memory,

positionstoa physical

and

memory

the

secondisperformed

and

Row

array.

and

Logic Sheet

Counter)

additionally,

The

two

two-bit

by a set

multiplexors.

The

first five-bit

Display Row

function

This between address data

current

during

might be displayed

adder

producesasum

Count

provides

display rows

+ Offset

the

required relationship

and

refresh scanning, in

on

the

proper

equal

Count

+ I

the virtual row-

order

that

rowofthe screen, consistent with the scroll-history since last clear-screen occurred, the offset the

top

row

memory-row

display-row data

for the

row

zero. Oneofthe two-bit gates, greater

performs

than23to a 24-row universe, by

appropriate

o+ I =

If

top

I =2)and

24~0).

the display has been scrolled one time,

row

will be

data row I, thus, it can be in

memory the display by one row, even

though

is

unchanged. The only physical example, occurs in (see section 4.3.8) leaving

for new

the

new

data-entry.

operation.

count

of

the display will be

If no scrolling has

will be zero,

and

obtained

I (0 + 0 + I= I). Likewise,

22

will come

bottom

from

row will

memory-row

come

from

adders,

plus associated

the functionofreconciling sums

adjustment

obtained

for the

will

appeartohave moved

its

actual

factortoall such sums (23 +

from

memory-row2(0

bottom

demonstrated

after

physical

row

from

that

the scrolling

locationinmemory

alteration,

memory-row

during

bottom

row address locations clear

I, which is erased

the

scroll

data

23,

memory-

adding

data

for the

memory-

all the

upward

operation,

in this

operation,

and

first

of

to:

the

for

at

for

and

an

+ I +

data

on

function

This position, must

appear

which determines

erased

and

scrolling

row,

the

desired

is row

from

row

of

refresh.Ifthe bottom 24

gate greater

is

data

row,

~

0),

set which reconciles all

than23to

consistent

entered

routedtomemory-row

As scrolling occurs, maintains cursor that row time as

position

data-entry

whichisdisplayed

the

reconciles

which is

on

rolledtothe

has

occurred

resultant

row

which

the

duetothe

with

under

the

cursor.

the

current

the

rowonwhich new

the

display,tothe

the

last

memory-row

bottomofthe

and

the

sum

for

data

will be

memory-row

data-entry,

obtained

cursor

sum

would

be zero (23 + 0 + I =

actionofa second

CR+OC

values between 0

the

refresh adder-set, since

these

circumstances

zero.

the

second proper and will always

relationship

the

virtual

occurinthe

during

Considerasanother

scroll-history,

cursorison

since

were

movedtothe

and

display-rows,

the

same

display which has been scrolled six rows,

the

cursorispositionedtorow

actually displayed

Ifan

entryismadeatthe

same

summation

and

Offset

Counter

madeinrow

The

multiplexor

manipulates

Logic

derived above, plus

Display

Column

Counter

the 80 x 24 display

matrix.

The

on

row

+ 6 + I =

20

will

occur

values,

3.

sectionofthe

the

CR+OC

the

Counter

(WCO - WC6) in

matrixtoa 64 x 30

first-stage between Refresh accesses accesses, since OC

sum

latter

are

the

former

and

the

CC

Counter

governedbythe

20.

The

20 will be:

27~3

current

cursor

using

and

Memory

and

information

(CCO - CC7)

multiplexors

to

memory

are

governedbythe

information,

CR+OC

the

RC+OC

ordertoresolve

sum

counter.

The

time-period

display-time

for

when

each

CC7isfalseisthe

scan-line,

and

cursor

row-

data-entries

that

was

display.Ifno

the

top

I, which

thatisthe

for

the

top

adder

+ 1

and

sums

23. This also any

will be

adder

between

group

the

such

memory-

row-scan example, after

which

memory-row

position,

Cursor

entry

the

Row

will be

Address

sums

from

the

and

Cursor

memory

distinguish

and

write RC

while

the

and

the

WC

active

therefore,

a

+

Lear Seigler ADM-3A Maintenance Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

4-10

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