Hazeltine 1500 User manual

HI-I056A

July

1977

•

aze

Ine

VIDEO DISPLAY TERMINAL

REFERENCE MANUAL

Hazeltine

Corporation

Compu

ter

Perip

h

eral

Equipment

Gree

n

lawh

. N Y 11740 (

516

)

549

":

8800

Telex

96-1435

HI-1056A

SAFETY

SUMMARY

WARNING

I

Dangerous voltages

(15

K vdc and 115 vac)

are

present

in

the Video

Display

Terminal

and may

remain

present

in

the

monitor

circuits

after

power

is

removed. Use caution when working

on

internal

cir-

cuits.

Do

not

work

alone.

Use caution when handling the

cathode-ray

tube (eg,

wear

safety

goggles) to avoid

risk

of implosion. The

internal

phosphor coating

is

toxic;

if

the tube

breaks

and

skin

or

eyes

are

exposed to phosphor,

rinse

with cold

water

and

consult

a physician.

This

manual

is

published

and

distributed

by

Hazel-

tine

Corporation,

Computer

Terminal

Equipment

Prod-

uct

Line.

The

contents

of

this

manual

are

subject

to

change

at

any

time

and

without

prior

notice

by

Hazeltine.

The

information

presented

herein

may

not

reflect

latest

changes

in

the

product.

Confir-

mation

and

any

required

clarification

of

this

in-

formation

can

be

obtained

from

your

local

Hazel-

tine

sales

representative.

Copyright

1977

by

Hazeltine

Corporation

Section

1

2

3

4

5

6

Appendix

I

II

III

IV

HI-I056A

CONTENTS

Introduction

Installation

...

2.1

Set-up

and

Connections

2.1.1

Interface

Connection

•••.

2.1.2

Power

Cords

.•••.

.

••

2.1.3

Cleaning

..•.••..•.•.

2.2

Turn

On

and

Warm Up

••.••..•..

2.2.1

Power

Turn-On

••.••••

2.2.2

Warm-Up

••••.•.•

Keyboard

and

Controls

• . • . • • •

3.1

Front

Panel

Switches

•..

3.1.1

General

.•.•••.•.•.•

3.1.2

Front

Panel

Switches

..•.

Operation

4.1

Introduction

4.2

Operation

in

Full

Duplex

4.3

Operation

in

Half

Duplex

4.4

Scrolling

.•••.••

4.5

Remote

Commands

•.••

4.5.1

General

4.5.2

Commands

••

4.6

Timing

Considerations

Communications

Interface

· ·

5.1

ASCII

. . . . · · · · •

5.2

Asynchronous

Data

· · ·

5.3

Full

Duplex/Half

Duplex

5.4

EIA

Interface

· · · · ·

5.5

Current

Loop

Interface

5.6

Hardwired

Interface

· ·

5.7

Data

Sets

. . · · ·

5.7.1

103A

Modern · · ·

5.7.2

202

Modern ·

Technical

Summary

APPENDIXES

ASCII

Character

Code

Chart

Cursor

Address

Chart

• • • •

Summary

of

Remote

Commands

•

Programming

"Example

• • • •

i

· . .

· · · ·

· · · · · · · ·

· · · ·

· · · · · ·

· · · · · · · ·

· · · · · ·

· • · ·

· · · · · ·

· . . .

· . .

· . . . . . . .

· .

· . . . . . . .

1-1

2-1

2-2

3-1

4-1

4-2

4-3

4-8

5-1

5-2

5-4

6-1

I-I

11-1

111-1

IV-l

Figure

2-1

3-1

3-2

5-1

Table

HI-I056A

ILLUSTRATIONS

H1500

Terminal,

Rear

View

• • .

•••.•••

2-2

Legend

Plate

(Under

Access

Panel)

• • • •

3-2

Keyboard

Controls

(for

reference

only)

• • • •

3-2

Current

Loop

Interface

• • • • • • •

••

•

5-3

TABLES

3-1

Transmitted

Characters

in

Half

and

Full

Duplex

Operation

• • • • •

••

••••••

3-6

ii

HI-I056A

SECTION I

INTRODUCTION

The

Hazeltine

1500

Video

Display

Terminal

(also

referred

to

as

the

Hazeltine

1500),

is

a

product

of

advanced

microprocessor

technology,

which

offers

quiet,

reliable,

and

economic

opera-

tion

to

the

user.

The

expanded

set

of

features,

all

standard

on

the

Hazeltine

1500,

are

normally

found

only

in

CRT's

of

the

buffered

or

editing

variety~

Speed,

silence,

and

flexibility,

coupled

with

the

operator-oriented

features

of

the

Hazeltine

1500

improve

the

efficiency

of

both

the

software

and

programmer

in

data

input/output

operations.

The

terminal

can

also

be

made

compatible

with

European

voltages

and

frequencies.

This

manual

describes

the

operation

and

features

of

the

Hazeltine

1500.

It

provides

programming

and

ap~lication

information

for

programmers

and

system

designers.

If

additional

technical

assis-

tance

is

needed,

contact

your

Hazeltine

representative.

Hazeltine

Corporation

Industrial

Products

Division

Greenlawn,

New

York

11740

Tel:

(516)

549-8800

Telex:

96-1435

1-1

HI-I056A

SECTION 2

INSTALLATION

2.1

SET-UP

AND

CONNECTIONS

Following

unpacking,

place

the

unit

so

that

free

air

circulates

around

the

rea~,

base

and

top.

Ensure

that

cables

are

free

of

kinks

or

tight

bends.

2.1.1

Interface

Connection

The

standard

Electronic

Industries

Association/Current

Loop

(EIA/CL)

connector

(figure

2-1)

located

on

the

rear

of

the

unit,

provides

the

connection

to

the

appropriate

data

set

or

the

acoustic

coupler.

The

connector

has

provisions

for

either

volt-

age

level

(EIA

RS232)

or

current

loop

interface.

The

Aux

Out

connector

(figure

2-1)

allows

connection

of

a

serial

EIA

receive-

only

device,

such

as

a

printer.

2.1.2

Power

Cords

Power

cords

must

be

plugged

into

properly

grounded

power

out-

lets.

Do

not

use

adapters

which

would

prevent

the

terminal

unit

from

being

properly

grounded.

2.1.3

Cleaning

Dirt

and

smudges

can

be

removed

from

the

cabinet

with

any

number

of

common

household

spray

cleaners

and

a

soft

cloth.

The

face-

plate

should

be

cleaned

only

with

a

soft,

damp

cloth

or

tissue

to

avoid

scratching.

2 •2

TURN

ON

AND

WARM

UP

A

display

unit

brought

in

from

a

substantially

colder

environment

should

be

allowed

at

least

a

one-hour

warm

up

period

to

reach

room

temperature

prior

to

power

turn-on.

2.2.1

Power

Turn-On

A

power-on

slide

switch

is

located

at

the

rear

of

the

terminal.

When

power

is

on,

the

POWER

ON

indicator

located

on

the

key-

board

is

lit.

Allow

at

least

15

seconds

to

elapse

between

power

off

and

power

on

in

the

event

of

unit

power

recycling.

If

the

POWER

ON

indicator

does

not

light,

the

terminal

should

be

2-1

ON/OFF

SWITCH'

HI-I056A

rigure

2-1.

H1500

Terminal,

Rear

View

turned

off.

After

15

seconds

depress

the

red

circuit

breaker

located

in

the

rear,

the

power

switch,

and

again

apply

power

to

the

terminal.

If

the

POWER

ON

indicator

still

does

not

light,

turn

power

off

and

call

your

authorized

service

rep-

resentative.

2.2.2

Warm

Up

Allow

30

seconds

for

display

warm

up.

At

the

end

of

this

period

the

terminal

is

ready

to

operate.

a.

If

extraneous

data

appears

and/or

the

cursor

is

not

displayed

in

the

upper

left

corner

(HOME),

depress

the

RESET

key,

followed

by

the

CLEAR

key

located

on

the

keyboard.

If

after

depressing

the

RESET

and

CLEAR

keys,

and

proper

display/

operation

is

still

not

obtained,

turn

the

power

off

and

contact

your

authorized

service

representative.

2-2

HI-1056A

b.

If

the

cursor

doe's

not

appear

after

the

display

has

warmed

up

for

a

reasonable

time

(no

more

than

three

minutes)

and

the

power

indicator

is

lit,

adjust

the

contrast

control

lo-

cated

under

the

access

panel

on

the

top

of

the

keyboard

(see

section

3.1.1).

If

the

cursor

still

does

not

appear,

turn

the

power

off

and

contact

your

authorized

service

representative.

2-3

HI-l056A

SECTION 3

KEYBOARD

AND

CONTROLS

3.1

FRONT

PANEL

SWITCHES

3.1.1

General

Eighteen

switches

used

for

selecting

the

operating

characteris-

tics

of

the

Hazeltine

1500

are

accessible

to

the

operator

with-

out

having

to

open

or

remove

power

from

the

terminal.

To

gain

access

to

these

switches,

remove

the

front

access

panel

engraved

with

the

POWER

ON

legend

by

lifting

up

the

catches

located

on

each

side

of

the

panel.

Replacement

of

the

panel

is

accomplished

by

placing

it

in

the

recessed

area

with

the

power

on

indicator

on

the

left,

and

gently

pressing

each

catch

into

position.

The

func-

tion

of

each

switch

and

function

key

is

described

in

the

para-

graphs

that

follow.

The

legend

plate

is

visible

when

the

access

panel

is

removed

(see

figures

3-1

and

3-2).

3.1.2

Front

Panel

Switches

a.

Baud

Rate

The

communication

speed

is

selected

by

Sliding

the

switch

the

desired

baud

rate

forward

to

the

ON

position.

Only

one

switch

for

each

baud

rate

is

allowed

to

be

in

the

ON

position.

Eight

speeds

ranging

from

110

baud

to

19,200

baud

are

available.

b.

Parity

Four

switches

are

supplied

for

selecting

the

parity

compatible

with

the

system.

Slide

the

switch

the

desired

parity

of

operation

forward

to

the

ON

position.

Only

one

switch

for

parity

should

be

in

the

ON

position.

The

four

parity

possi-

bilities

are:

EWN

ODD

Checks

for

even

parity

on

received

data

and

generates

even

parity

on

outgoing

data.

Checks

for

odd

parity

on

received

data

and

generates

odd

parity

on

outgoing

data.

3-1

HI-1056A

Figure

3-1.

Legend

Plate

(Under

Access

Panel)

ACCESS

PANEL

figure

3-2.

Keyboard

Controls

(for

reference

only)

3-2

1

HI-I056A

The

parity

bit

of

each

character

trans-

mitted

is

set

to

a

one.

No

parity

check

is

done

on

received

data.

The

parity

bit

of

each

character

trans-

mitted

is

set

to

a

zero.

No

parity

check

is

done

on

received

data.

NOTE

If

a

character

is

received

with

a

parity

error

when

EVEN

or

ODD

parity

is

selected,

the

char-

acter

will

be

replaced

on

the

display

with

a

~

symbol.

c.

HALF

DUP-FULL

(1)

FULL

(Duplex)

The

rear

position

of

this

switch

selects

the

full

du-

plex

mode

of

communications

which

is

typically

used

when

the

communications

system

is

capable

of

simultaneous

two-way

trans-

mission.

In

this

mode,

data

entered

from

the

keyboard

is

sent

directly

to

the

computer

system.

Upon

reaching

the

computer,

the

data

is

typically

"echoed"

back

to

the

Hazeltine

1500

screen

at

the

discretion

of

the

program

(ie,

it

may

not

be

desirable

to

echo

back

special

codes,

passwords,

etc).

If

modems

are

used,

they

must

be

set

for

full

duplex

operation.

Only

received

or

"echoed"

data

is

displayed

or

acted

upon.

(2)

HALF

(Duplex)

The

forward

position

of

this

switch

selects

the

half-duplex.mode

of

communications.

In

this

mode,

data

entered

from

the

keyboard

is

sent

directly

to

the

computer

system

and

is

treated

as

received

data

by

the

terminal

via

an

internal

connection.

Echoing,

as

in

full

duplex

mode,

is

not

required;

if

used,

it

would

likely

cause

each

transmitted

char-

acter

to

be

displayed

twice.

3-3

HI-I056A

d.

AUTO

LF-CR

(1)

AUTO

LF

(Automatic

Line

Feed)

In

the

forward

position

of

this

switch,

all

re~

ceived

carriage

returns

automatically

cause

the

cursor

to

move

to

the

first

character

position

of

the

(new

line

func-

I

tion).

The

carriage

return

code

(ASCII

CR

column

0,

row

13)

shall

not

be

stored

in

the

display

memory.

If

the

cursor

was

on

the

last

displayable

character

row,

carriage

returns

will

scroll

the

display

(refer

to

section

4.4

for

a

description

of

scrolling).

Received

line

feed

characters

(ASCII

LF

column

0,

row

10)

are

ignored.

(2)

CR

(Carriage

Return)

In

the

rear

position

of

this

switch,

received

carriage

returns

move

the

cursor

to

the

first

character

position

of

the

same

line.

The

CR

code

is

not

stored

in

the

display

memory.

Received

LF

characters

move

the

cursor

down

one

line.

If

the

cursor

was

on

the

last

displayable

character

row,

Line

Feed

characters

will

cause

the

display

to

scroll

(refer

to

section

4.4

for

a

description

of

scrolling).

The

LF

code

is

not

stored

in

the

display

memory.

e.

U/L

CASE-UP

(1)

UP

(Upper

case)

The

rear

position

of

this

switch

selects

only

upper

case

operation.

All

lower

alpha

characters

generated

from

the

keyboard

are

converted

to

upper

case

for

transmission

and

display.

All

received

lower

case

alpha

characters

are

displayed

as

upper

case.

In

this

position,

the

ALL

CAPS

key

is

logically

disabled.

(2)

UIL

CASE

(Upper

and

lower

case)

The

forward

position

of

this

switch

selects

the

full

128

character

ASCII

codes

for

transmission

and

94

character

alpha/numeric

character

set

for

display_

In

this

position,

the

ALL

CAPS

key

in

the

down

position

may

be

used

for

upper

case

operation.

3-4

HI-l056A

f.

STD

VIDEO-REV

(1)

STD

VIDEO

The

forward

position

of

this

switch

selects

a

display

of

white

characters

on

a

black

background.

(2)

REV

(Reverse

Video)

The

rear

position

of

this

switch

selects

a

display

of

black

characters

on

a

white

background.

g.

ErA-CUR

LOOP

Both

switches

must

be

positioned

for

the

same

selection.

(1)

EIA

The

forward

position

of

these

switches

selects

EIA

RS232

communications

at

the

modem

interface

located

on

the

rear

panel.

(2)

CUR

LOOP

The

rear

position

of

these

switches

selects

20

rnA

current

loop

communications

at

the

modem

interface

located

on

the

rear

panel.

h.

Unused

Switches

Six

switches

are

provided

on

the

unit

for

expansion

possibilities.

These

switches

are

inoperative

on

the

Hazeltine

1500

and

its

operation

is

independent

of

the

position

of

these

switches.

i.

Contrast

Control

This

control

is

located

to

the

right

of

the

switch

array

under

the

access

panel.

It

allows

a

wide

range

of

con-

trast

to

facilitate

viewing

ease

of

the

high

resolution

display.

j.

Keyboard

All

keys

and

key

combinations

generating

ASCII

codes

operate

as

typamatic.

Depressing

any

of

these

keys

for

more

than

0.75

seconds

causes

the

character

to

repeat

at

an

approximate

rate

of

15

characters/second

with

transmission

at

the

selected

baud

rate.

The

typamatic

feature

is

designed

with

a

memory

that

3-5

HI-1056A

allows

the

SHIFT

and

CTRL

keys

to

be

released

without

altering

the

data

after

the

typamatic

feature

has

been

initiated.

The

descriptions

below

define

the

operation

of

the

particular

key

depression

in

the

half

duplex

mode

or

in

full

duplex

if

"echoing"

is

being

performed

by

the

computer.

Table

3-1

indicates

the

actual

character(s)

that

is

being

transmitted.

The

last

two

columns

of

the

table

give

a

brief

description

of

the

operation

described

in

detail

below.

Table

3-1.

Transmitted

Characters

in

Half

and

Full

Duplex

Operation

Key

Stroke

ESC

DEL

(SHIFT_)

RETURN

LINE

FEED

SHIFT

LINE

FEED

BACK

SPACE

SHIFT

BACK

SPACE

ALL

CAPS

TAB

BREAK

RESET

HOME

CLEAR

SHIFT

CLEAR

CONTROL

CLEAR

Transmitted

Character(s)*

Operation

in

half

~------------~------------~

duplex

or

in

full

Half

Duplex

ESC

DEL

CR

LF

None

BS

None

HT

Full

Duplex

ESC

DEL

CR

LF

'V,

FF

BS

DLE

None

HT

duplex

if

"echoed"

Transmission

Only

Transmission

Only

AUTO

LF -New

Line

CR

-

Line

Return

AUTO

LF -

Trans-

mission

only

CR

-

Line

Feed

Cursor

Up

Cursor

Left

Cursor

Right

See

Description

TAB

(Break

Signal)

(Break

Signal)

Transmission

Only;

See

Description

None

'V,

DC2

'V,

FS

'V,

GS

'V

I

SI

See

Description

Cursor

Home

Clear

Screen

CONTROL-SHIFT

CLEAR

None

'V,

CAN

Alphanumeric

Clear

Foreground

Clear-End-of-Line

Clear-End-of-Screen

See

Description

~PHANUMERIC

Alphanumeric

*

See

Appendix

I

for

the

ASCII

code

set

3-6

Operation

in

full

duplex

with

no

"echo"

Transmiss.;ion

Only

Transmission

Only

Transmission

Only

Transmission

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Transmission

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See

Description

Transmission

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Transmission

Only;

See

Description

See

Description

Transmission

Only

Transmission

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Transmission

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Transmission

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Transmission

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Transmission

Only

C77041

HI-I056A

(1)

Alphanumeric

Cluster

The

keys

in

this

cluster

transmit

the

ASCII

codes

(see

Appendix

I)

associated

with

the

engraved

legends

shown

in

figure

3-2.

When

used

in

conjunction

with

the

CTRL

and

SHIFT

keys,

it

is

possible

to

transmit

all

128

codes

in

the

ASCII

chart.

(a)

ESC

(Escape)

When

depressed,

this

key

will

transmit

the

ESC

code

(ASCII

ESC,

column

1

row

11)

which

is

commonly

used

to

generate

a

program

interrupt

signal.

(b)

DEL

(Rubout)

When

depressed

in

conjunction

with

the

SHIFT

key,-

it

causes

a

character

of

all

"one"

bits

to

be

transmitted

(ASCII

DEL,

column

7,

row

15).

(c)

RETURN

The

operation

of

this

key

is

governed

by

the

AUTO

LF-CR

switch

located

under

the

access

panel.

When

the

AUTO

LF-CR

switch

is

in

AUTO

LF,

depressing

the

RETURN

key

transmits

the

carriage

return

(CR)

coda

and

causes

the

cursor

to

move

to

the

first

character

position

of

the

If

the

cursor

is

on

the

bottom

line,

scrolling

occurs

(see

Sec-

tion

4.4).

When

the

AUTO

LF-CR

switch

is

in

CR,

depressing

the

RETURN

key

transmits

a

CR

code

and

causes

the

cursor

to

move

to

the

beginnin.g

of

the

same

line

,.

(d)

LINE

FEED

Operation

of

this

key

is

governed

by

the

position

of

the

AUTO

LF-CR

switch.

With

the

switch

in

AUTO

LF,

depressing

LINE

FEED

key

transmits

the

line

feed

code

but

has

no

effect

on

the

display

or

cursor

position.

With

the

switch

in

CR,

depressing

LINE FEED

key

transmits

the

line

feed

code

and

causes

the

cursor

to

move

down

one

line.

If

the

cursor

is

bn

the

bottom

line,

scrolling

occurs

(see

Section

4.4).

If

the

LINE

FEED

key

is

depressed

in

conjunction

with

the

SHIFT

key,

the

cursor

moves

up

one

line.

3-7

HI-l056A

(e)

ALL

CAPS

Operates

in

conjunction

with

the

lower

case

fe~ture.

When

in

the

up

position,

the

keyboard

operates

as

a

standard

typewriter.

Typed

characters

are

dis-

I,

played

as

lower

case;

upper

case

characters

or

symbols

are

displayed

when

the

SHIFT

key

is

used

simultaneously

with

the

character

entry.

In

the

down

position,

the

keyboard

operates

like

a TTY.

Alpha

characters

only

are

displayed

as

upper

case;

depressing

other

keys

causes

the

transmission

of

the

unshifted

characters.

(f)

BACK

SPACE

When

depressed,

this

key

transmits

the

BS

code

(ASCII

BS,

column

0

row

8)

and

moves

the

cursor

one

position

to

the

left.

When

the

BACK

SPACE

key

is

depressed

in

conjunction

with

the

SHIFT

key,

the

cursor

moves

one

position

to

the

right

(non-

destructive

space

-

ASCII

DLE,

column

1

row

0).

If

the

cursor

were

in

the

first

position

of

a

row,

other

than

the

HOME

position,

de-

pressing

the

BACK

SPACE

key

causes

an

up-wraparound

to

the

last

char-

acter

position

of

the

row.

If

in

HOME,

no

action

will

result.

(g)

TAB

When

depressed,

this

key

transmits

the

HT

code

(ASCII

HT,

column

0

row

9)

and

moves

the

cursor

to

the

field.

If

a

new

foreground

field

is

not

present

by

the

end

of

the

24th

line,

the

cursor

will

not

move.

(2)

Standard

Functions

functions.

Keys

in

this

cluster

provide

commonly

used

(a)

BREAK

Depressing

this

key

generates

a

break

signal

to

the

computer

which

is

equivalent

to

the

corresponding

button

on

a

conventional

teletype

terminal.

3-8

HI-I056A

(b)

RESET

Depressing

this

key

blanks

the

display

until

the

key

is

released.

After

reset,

all

subsequent

re-

ceived

data

is

displayed

in

background

intensity

or

as

con-

trolled

by

subsequent

remote

commands.

This

key

is

independent

of

the

Half-Full

Duplex

Mode

setting.

(c)

HOME

Depressing

this

key

moves

the

cursor

to

the

home

position

(upper

left

corner)

.

(d)

CLEAR

This

key

is

used

in

conjunction

with

the

SHIFT

and

CTRL

keys

to

generate

four

different

clear

functions.

All

of

these

clear

to

foreground

spaces.

The

four

are:

CLEAR

Clear

Foreground

Clear

End

of

Line

-

depressing

this

key

alone

clears

the

total

display;

cursor

goes

to

home

position.

-

depressing

SHIFT

and

CLEAR

keys

clears

all

foreground

displayed

data;

cursor

goes

to

home

position.

-

depressing

CTRL

and

CLEAR

keys

clears

all

data

from

cursor

position

to

end

of

line;

cursor

does

not

move.

Clear

End

of

Screen

-

depressing

CTRL,

SHIFT,

and

CLEAR

keys

clears

all

data

from

the

cursor

to

the

end

of

screen;

cursor

does

not

move.

(3)

Numeric

Cluster

A

separate

numeric

key

cluster

is

provided

for

added

operator

convenience.

These

keys

operate

in

exactly

the

same

manner

as

the

alphanumeric

keys

except

that

they

are

not

affected

by

the

SHIFT

or

CTRL

keys.

3-9

HI-I056A

SECTION 4

OPERATION

4.1

INTRODUCTION

The

basic

mode

of

operation

for

the

Hazeltine

1500

Video

Display

T~+minal

is

character-by-character

(switch

setting

at

HALF

or

FULL

DUPLEX).

Data

which

is

entered

via

the

keyboard

is

sent

directly

to

the

computer.

A

wide

variety

of

editing

and

formatting

functions

are

available

through

the

use

of

the

various

remote

commands

(see

Section

4.5).

As

an

example,

most

computer

based

software

packages

recognize

special

characters

and

have

subroutines

for

backspacing

and,

in

some

cases,

line

and

character

replacement.

4.2

OPERATION IN

FULL

DUPLEX

The

full

duplex

mode

of

communication

is

typically

used

when

the

communication

system

is

capable

of

simultaneous

two-way

transmission.

Data

entered

via

the

keyboard

is

routed

directly

to

the

computer

without

display.

The

display

is

comprised

only

of

alphanumeric

data

"received"

by

or

"echoed"

back

to

the

terminal.

Each

display

function

key

(ie,

HOME,

CLEAR,

etc)

generates

a

code

that

is

transmitted

to

the

computer,

and,

under

computer

control,

is

"echoed"

back

to

the

terminal.

The

ASCII

code

for

each

of

these

display

functions

is

included

in

paragraph

4.5.2.

4.3

OPERATION IN

HALF

DUPLEX

The

Half

Duplex

mode

of

communication

is

used

when

the

communica-

tion

system

is

not

capable

of

simultaneous

two-way

transmission,

or

the

"echoed"

back

operation

is

undesirable.

Data

keyed

from

the

keyboard

is

transmitted

and

displayed

simultaneously.

The

data

displayed

is

processed

as

if

it

were

data

transmitted

by

the

computer.

Display

function

keys

do

not

generate

codes

in

Half

Duplex.

4.4

SCROLLING

If

a

displayable

ASCII

code

is

received

at

the

last

character

position

of

the

last

displayable

character

row,

the

data

moves

4-1

HI-l056A

up

one

~ow(

the

top

row

of

data

is

removed,

and

the

cursor

moves

to

the

first

character

position

(left

margin)

of

the

last

(bot-

tom)

character

row.

Data

from

the

last

character

row

is

re-

placed

with

spaces.

This

type

of

manipulation

and

cursor

move-

ment

operation

is

referred

to

hereafter

as

scrolling

and

re-

quires

no

fill

characters

at

any

baud

rate.

Scrolling

also

occurs

when

the

cursor

is

on

the

bottom

line

and

a

line

feed

(ASCII

LF)

is

received

in

CR

operation

or

a

carriage

return

(ASCII

CR)

is

received

in

AUTO

LF

operation

as

selected

by

the

AUTO

LF-CR

switch.

4.5

REMOTE

COMMANDS

4.5.1

General

The

remote

command

features

of

the

Hazeltine

1500

provide

the

user

with

the

capability

to

fully

control

the

terminal

via

the

CPU

software.

In

order

to

call

a

terminal

function

from

soft-

ware,

it

is

necessary

to

precede

the

function

code

with

a

lead-

in

code

(except

as

noted).

The

lead-in

code

(ASCII'V,

column

7,

row

14

-

Decimal

126)

alerts

the

terminal

that

a

special

func-

tion

follows.

The

lead-in

code

and

the

command

following

the

lead-in

code

when

received,

is

not

stored

in

display

memory

and

does

not

advance

the

cursor.

If

the

code

following

the

lead-in

code

is

not

one

of

the

valid

command

codes

(a

second

lead-in

is

invalid),

that

code

will

not

be

stored

and

the

cursor

will

not

advance.

NOTE

1.

The

command

code

must

immediately

follow

the

lead-in

code

without

any

intervening

characters

(including

NUL

or

DEL) •

2.

3.

Terminology:

X

represents

the

column

on

the

screen

0

through

79 (0 < X

~79)

y

represents

the

row

on

the

screen

0

through

23

(0

~

y

~23)

Appendix

III

summarizes

the

remote

commands.

described

below;

Appendix

IV

gives

a

programming

example

using

the

cursor

addressing

remote

com-

mand;

the

ASCII

code

chart

is

shown

in

Appendix

I.

4-2

HI-l056A

4.5.2

Commands

a.

Home

Cursor

(lead-in

required)

On

receipt

of

the

HOME

CURSOR

command

(ASCII

DC2,

column

1,

row

2 -

Decimal

18),

the

cursor

moves

to

the

upper

left

corner

of

the

display

(coordinates

X =

0,

Y =

0).

This

has

no

effect

on

data

displayed.

b.

Up

Cursor

(lead-in

required)

On

receipt

of

the

UP

CURSOR

command

(ASCII

FF,

column

0,

row

12

-

Decimal

12),

the

cursor

increments

up

one

row

without

altering

the

display.

If

the

cursor

is

located

in

the

top

row

(Y=O),

there

will

be

no

cursor

movement.

c.

Down

Cursor

(lead-in

required)

On

receipt

of

the

DOWN

CURSOR

command

(ASCII

VT,

column

0,

row

11

-

Decimal

11),

the

cursor

increments

down

one

row

without

altering

the

display.

If

the

cursor

is

located

in

the

bottom

row

(Y=23),

there

will

be

no

cursor

movement.

d.

Left

Cursor

(no

lead-in

required)

On

receipt

of

the

LEFT

CURSOR

command

(ASCII

BS,

column

0,

row

8 -

Decimal

8),

the

cursor

moves

back

one

character

position

and

does

not

alter

the

display.

If

the

cursor

is

in

the

leftmost

column

(X=O) ,

it

will

wrap

backward

to

the

row

above

and

the

right-most

column

(X=79).

If

the

'cursor

were

in

the

home

posi-

tion

(X=Y=O),

it

would

not

move.

e.

Right

Cursor

(no

lead-in

required)

On

receipt

of

the

RIGHT

CURSOR

command

(ASCII

DLE,

column

1,

row

0 -

Decimal

16),

the

cursor

ad-

vances

one

character

position

to

the

right

and

does

not

alter

the

display

(non-destructive

space).

The

code

is

not

stored

in

display

memory.

If

the

cursor

is

in

the

rightmost

column

(X=79),

it

wraps

around

4-3

hazeltine 1500 User manual

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