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Document:	LA100-Series Programmer Reference Manual
Order Number:	EK-LA100-RG
Revision:	001
Pages:	66
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EK-LA100-RG-001

LA100-Series
Programmer
Reference Manudl

EK-LA100-RG-001

LA100-Series
Programmer
Reference Manuadl

Digital Equipment Corporation « Bedford, MA 01730

;\f“‘\\wmm«w%

lst Edition,

1982

by Digital

All

The material
purposes and

in
is

Rights

this manual is for informational
subject to change without notice.

Printed

following

Corporation,

are

trademarks

Maynard,

assumes no
that may appear

Digital

Massachusetts.

DECnet

IAS

DECUS

DECsystem-10

MASSBUS

Logo

DECsystem-20

PDT

DECwriter

RSTS

UNIBUS

DIBOL

RSX

VAX

EduSystem

VMS
VT

4/82-15

U.S.A.

DEC

Digital
PDP

Corporation

Reserved

Digital Equipment Corporation
responsibility for any errors
this manual.

The

Equipment

January

Equipment

1982

CONTENTS

INTRODUCTION

CHAPTER

COMMUNICATION

General

Serial Character
Break Signal

Format

Character Transmit
EIA

Interface

Modem

and Receive Rates

Control

Disconnect

Input
CHAPTER

Buffer

CHARACTER

Overflow Prevention

PROCESSING

General
Introduction

Printable Characters
Control Characters
Escape and Control Sequences
Control Strings
Answerback Message
Graphics

iii

INTRODUCTION

The Letterprinter 100 User Documentation Packages cover all
Letterprinter 100 model terminals. The User Documentation 1is

written for three general audiences:

the hardware installer requiring
and checkout information,

specific

installation

the operator requiring general operating information,
the applications programmer
control function descriptions.

requiring

interface

and

The documentation for the Letterprinter 100 is divided into
three

books:

Installation Guide
Operator Guide

Programmer Reference Guide

This book describes the interface and receive character processing information for the Letterprinter 100 terminals. The

programmer should use this manual as a reference when writing
application software.

The

Programmer

Reference

Guide

1is

divided

into

the

following

chapters:

Chapter

Communication

communication

describes

the

terminal

interface

Chapter 2 Character Processing -- describes the terminal
to

printable characters control

control

and

features.

characters,

response

escape sequences,

and

strings.

WARNINGS,

CAUTIONS AND NOTES

In this book, warnings, cautions, and notes are used for specific
purposes. Warnings are used to highlight information used to
Cautions highlight information used to
prevent personal injury.
Notes are used to highlight
prevent damage to the terminal.
general

information.

oiy,

CHAPTER

COMMUNICATION

GENERAL

This chapter describes LAl0@ communication interfaces and
terminal communication features. The communication features

the
are

used
to
configure
the
terminals
to
operate
with
specific
computers.
This chapter also discusses the methods of controlling
data received by the terminal to avoid input buffer overflows.
SERIAL CHARACTER FORMAT

The LA19@ communicates using serial characters (Figure 1-1). The
serial character format for the terminal must match the character
format used by the computer. Serial characters are transmitted
using a start bit, 7 or 8 data bits, a selectable parity bit and 2
stop bits.

NOTE:\n\nIf you are using the LAl12X-BB Parallel Interface option,
refer to the option installation guide for character format
information.

The

data

leading.

bits
If

forced

BREAK

SIGNAL

the

ignored
when
selectablee

A break
+

the computer

EIA

signal

INTERFACE

bit

space

The

and

bit

characters

receiving

signal

10 percent.

break

represent

(@)

character, least

are

condition

characters.

transmitted

response

fault

paper

and

The

significant

the

last

parity

bit

the

eighth

data

bit

1is

operator

for

#.275

seconds

the

LAl00 sends a

asynchronous
1is
a
DB-25

communication
male
25 pin

space condition

computer

the software used.

when

selected,

the break signal depends on

If selected,

occurs.

INFORMATION

The terminal operates on full-duplex,
lines.
The
EIA
1interface
<connector

connector mounted on the back of the terminal
(Figure 1-2).
The
LA10@
EIA
interface
signals
meet
the
EIA
specification
requirements
RS-232-C
and
the
International
Telephone
and
Telegraph Consulting Committee (CCITT) recommendation V.24,

IDLE

START BIT OF

STATE OF

NEW CHARACTER

LINE

Jors

DATA BITS

"SPACE" +

(m-r-wmwmw*"r“?"'rg?lr

lt,sa' 01 | 021 03] 04 | 05 | 06 | S I

“MARK' —

START
BIT

ONE BIT
TIME =

ONE/

BAUD RATE

WHEN
8-BIT

-]STOPlSTOP

OPTIONAL RETURN TO IDLE
PARITY STATE OF LINE

CHARACTERS
ARE USED

zarrs

BIT

gth gIT=0
MA-TEBIBA

Figure

1-1

Serial

Character

Format

PIN 13

fi
o

o O

e PIN 25 »

QO
Q
00

OO
00

0‘0

Q
O
OO

)

PIN 1

°,
o

o ©

PIN 14

25 PIN MALE CONNECTOR

“

Ma-7255

Figure

1-2

EIA Connector

terminal

ft)

current

connected

away without

the

use

loop

interface

directly

to
of
a modem.

option

computer

allows

305

the

(1009

Table 1-1 summarizes the ETA connector signals and the followin
g
paragraphs
explain
each
signal
as
used
in
the
LAl10@.
The
Communication
Feature
section
explains
the
effect
that
the
communication features have on the EIA control signals.
Protective

This

Ground

circuit

also
power

is connected to the chassis of the terminal.
It
is
connected to external grounds through the third wire of the
cord.

Transmitted

Data

(TXD)

Direction:

From

-terminal

Signals

this

circuit

are

generated

Received

Data

(RXD)

Direction:

Signals on

this

are

represent

circuit

the

represent

Send

(RTS)

From

terminal

RTS

Clear

Send

Direction:
This

that

serially encoded

characters

that

on,

the

(CTS)

the

CTS

terminal

circuit

monitors

transmit
selected,

any
CTS

Data

Ready

Set

characters

equipment.

signal

response

The
not

Direction:

encoded

user's

Direction:
the

serially

terminal.

When

terminal

generated

Request

the

RTS.

With

modem

codes
if
1s always
(DSR)

terminal

intends

signal

generated

control

protective

modem

LAl¢@0 will not
modem
control
|

terminal

the data set is ready. The terminal will
data
until
this signal
is on.
With no

ground

on.

The

DSR

This circuit establishes
all interface circuits.

the

data.

modem control selected,
DSR is always assumed to
indicator lights when the DSR signal is received.
Ground

selected, the
CTS
1is
not
on.
With
no
assumed to be on.

DSR signal is on when
transmit
or
receive

Signal

receive

a common ground reference potential for
This circuit is permanently connected to

circuit.

NOTE :\n\nThe

Table 1-1

.
.

EIA Interface Signals
CCITT/EIA

Name

Mnemonic Designation

1
2
3

Protective Ground
Transmitted Data
Received Data

PGND
TXD
RXD

6
7
8

Request to Send
Clear to Send
Data Set Ready
Signal Ground
Receive Line

9
19

No Connection

4
5

12
13

Signal

Speed Indicator
No Connection

Connection

Send

User

LA190
User

SPDI

SRTS

120/SCA

LAl1QO

DTR

198.2/CD

LA10Q

SPDS

111/CH

LAl1G@

No Connection

Secondary Request
Data Terminal
Ready

No Connection

Speed Select

Connection

No Connection

BUSY

Restraint

Connection

LAl1O®
User
User

No Connection

185/CA
106/CB
187/CC
102/AB
109/CF

LA10GO
User

Detect

RTS
CTS
DSR
SGND
RLSD

101 /AA
163/BA
104/BB

Source

No Connection

Receive

Line

Direction:

Signal

Detect

(RLSD)

terminal

When

the
RLSD
signal
is
on,
it
indicates
that
the
modem
has
received
the data carrier signal.
The terminal will not receive
data until this signal is on. With no modem control selected, RLSD

always

assumed

Restraint

(BUSY)

Direction:

From

on.

- Pin 11
terminal

With restraint selected, the on
the computer should temporarily

off,

the

Speed

computer

Indicator

Direction:

can

resume

(SPDI)

condition of BUSY
stop sending data.

sending

indicates
When BUSY

that
goes

data.

terminal

With speed mode selected,
the terminal operates at the operator
selected baud rate when SPDI is off. The terminal operates at 1200
baud regardless of the operator selected rate when SPDI is on.

Secondary Request to Send

Direction:

Same as
Data

From

restraint

Terminal

Direction:
When

the

signal

the

terminal

on,

the

Indicator

speed

Otherwise

SPDS

CIRCUIT

baud

kept

capable

processing

receiving

disconnect

and
the
receive
baud
rate
of
higher,
the
terminal
turns
SPDS

the
on.

JUMPERS

EIA

circuits

can

physically

jumper:
Ground

connector

EIA

Indicator

Secondary

Speed

off.

Busy

Speed

Protective
-

terminal

selected,

1200

following
a

terminal

mode

1is

removing

(SPDS)

From

terminal

The

(DTR)

terminal
is

Speed

"EIA

11)

When

Direction:
With

- Pin 19

DTR is off,
terminal is local.

data.

the

(pin

Ready

From

DTR

(SRTS)

terminal

Request

Select

EIA

EIA
to

connector

connector
Send

disconnected

connector

EIA

When

connector

any
of
the
EIA circuit
jumpers
are
removed,
the
loopback
control line test fails. Refer to the jumper removal procedure in
the Installation guide to remove any of the EIA circuit jumpers.

CONNECTING TO THE COMPUTER

The LAl1@# can be connected to a computer directly or through a
common carrier facility (telephone line) as shown in Figure 1-3.
The EIA interface or optional 20mA current loop interface can be
used

in both applications.

When connecting the terminal to the computer through the telephone
line, a modem (data set) is needed. The modem changes the serial

characters transmitted between the terminal and the computer into

signals that can be transmitted over the telephone lines. Several
types of modems can be used with the LAl0@. However, the modem
used by the terminal must be compatible with the modem used by the

computer.

The type of communication used by the terminal must also be
compatible with the computer and the communication system. The
of

type

(SET-UP

communication

is used

for

used

the

LAl@#@

the Letterwriter

are used for the Letterprinter 100).

100,

operator

selectable

communication switches

MODEM CONTROL

When on-line, the LAl@@ is connected to the communication line and
terminal
The
data.
sending
and
receiving
of
capable
is
duplex
full
on
EIA compatible devices
communicates with
asynchronous communication lines.

full-duplex
of
types
Dbasic
two
supports
terminal
The
communication; with or without modem control. Both methods allow
received at the same time. When
data to be transmitted and
the data
selected,
is
full-duplex with no modem control
transmission and reception is always enabled when not in local.
Full-duplex with modem control requires that both the terminal and

the

modem

data.

recognize

the

proper

EIA

signals

before

transmitting

Table 1-2 shows the effect of the modem/no modem feature on

the EIA control

signals.

No modem control allows the terminal to communicate directly with
a computer (null modem configurations) or with full-duplex modems
that do not support DSR (data set ready) or RLSD (receive line
signal

indicator).

Modem control

allows the

terminal

communicate

such as Bell 103, 212, Vadic 3400, or equivalent.

through modems

COMPUTER

TERMINAL

COMPUTER

TERMINAL

MA-T776C

Figure

1-3

Connecting to the Computer

‘”"‘%«

Table

1-2

Modem Control

EIA

Signal

Affect

Modem

Control

DTR

active

RTS

active

CTS

inactive

active

TXD
RXD
DSR
RLSD

EIA Signals

active
active
inactive
inactive

active
active
active
active

Key

Off
Active
On
Inactive

Signal off at EIA connector
Signal turns on or off depending on terminal state.
Signal on at EIA connector
Signal
1ignored
at
EIA
connector
but
terminal
internally forces signal on.

FULL-DUPLEX

DISCONNECT

full-duplex

terminal

disconnect

ready)

off

for

accomplished

turning

DTR

(data

least two seconds plus the DSR
(data
set
ready)
delay
time,
but
no
greater
than
3.8
seconds.
The
following conditions cause a full-duplex disconnect.
[

DSR

turns

RLSD

off

turns

Wrong

within

the

paper

for

time

out

than

(DSR

two

seconds

on,

fault

condition

EOT

key

control

RLSD

does

not

turn

switch

set

until

disconnect

and

occurs

If the terminal
is switched to
100,
press
SELF TEST
key;
for

LINE/LOC

then

seconds)

paper

out

DTR

off

number

after

LINE

character

local
(for Letterprinter
Letterwriter
100,
press

indicator

received

goes

while

off)
coded

disconnect

enabled
INPUT BUFFER OVERFLOW PREVENTION
When the LAl00@
receives a character

(other

characters),

the

character
are

input

removed

falls

tone

are

the
4008

occurs,

placed

three

and

the

1is

the

character

the

input

avoid

and

DEL

its

4009

characters

the

terminal

input
lost,

buffer

input

NUL

ready,

printed.

characters,

ways

than

character

terminal

buffer

than

overflow

There

stores

When

input

character

sounds.

the

control

terminal

buffer.

from

behind

overflows.

SUB

the

and

buffer

buffer
a

single

the

bell

overflows.

Use the XON/XOFF or restraint feature to signal the data
source when to
temporarily stop or
resume sending data.

Using

the

XON/XOFF

restraint

feature

allows

maximum

throughput

and
eliminates
the
need
for
fill
character
calculations and message size limits. These features are
explained in detail later in this chapter.
2.

Send
data
only
as
fast
as
it
can
be
printed.
When
receiving data at 1200 baud or less the terminal can keep
up with
character
reception.
However,
very short
1lines
and
multiple
form
feeds
are
not
processed
this
fast.
Also, characters received faster than 1200 baud cannot be
processed

that

quickly.

these

cases,

are
used
to
slow down
the
effective
speed. Fill time formulas are given in

Time
3.

Limit

Formulas

characters

section.

the

number

terminal's

input

characters

buffer

the
beginning
of
receive
a
message

overflow.

fill

data
transmission
the following Fill

the
of

the
message
to
the
the buffer is empty at
transmission,
the
terminal
can
400
characters
without
a
buffer

size.

XON/XOFF and Restraint

The XON/XOFF and restraint features are used to prevent input
buffer overflows. When XON/XOFF and/or restraint is selected, the
terminal constantly monitors the number of characters stored 1in
buffer.

input

the

The

computer

the

signals

terminal

stop

(sends XOFF control character or sets the restraint

sending data

signal off) when any of the following conditions occur:
of

Number

fat

Terminal

input

the

(sends

XON

transmits XOFF and

signals

terminal

The

characters

exceeds

buffer

200

characters

control

computer

the

character

then

sets

receives 60 characters

resume

the

when any of the following conditions occur:

data

restraint

transmission
signal

on)

When the number of characters in the input buffer is less

than

characters

Terminal is switched on-line

restraint

XON/XOFF

and

Fill

Formulas

Time

(or powered up on-line)

selectable

operator

are

features.,

When receiving data at 1200 baud or less, the terminal can keep up
with normal character reception. Very short 1lines and multiple
form
used

feeds cannot be printed this fast. Fill characters may be
to slow down the effective data transmission speed in these
cases. Fill characters do not enter the input buffer they are
stripped out of the data stream upon reception.

The terminal's printhead and form movements (horizontal and
vertical) terminal are directly related to the fill time required

to slow down the effective data transmission speed.

The fill time

required to compensate for these movements can be converted to the
number of fill characters needed using the following formula.
Number of

Fill Characters

Fill Time Required
Character

Execution Time

NOTE:\n\nNUL is the only recommended fill character even though
some other characters may seem to achieve the same result in
special

cases.

Determining Fill Time Required

Required fill time for horizontal Movement (including tabs
positoning sequences) is determined in the following way.
First figure the actual number of columns moved.

Then,

and

allow 15 ms

for each of the first 10 columns (3@ ms in double-width pitches:
5, 6, 6.6, 8.25) and 5.5 ms for each additional column (11 ms in

double-width

pitches).

Required
fill
time
for
vertical
movement
(includes
linefeeds,
vertical tabs, form feeds, and vertical positioning sequences)
is
determined in the following way.
First
using

convert the number of
the following formula.

Inches

Moved

Number

lines

Vertical
Then

allow

for

given

ms for the first
additional inch.

down
the
Character

Table

Fill

Time
1.

baud

rate.

effective
execution

actual

distance

moved

Moved

line

moved

1/6

inch,

and

200

is given in milliseconds and is based
the time the computer takes to slow

data
times

Pitch

Character Execution Time
The character execution time

Lines

each

moved

transmission
speed
to
the
at the applicable baud rates

terminal.
are shown

1-3.

Formula

Examples

Horizontal
Assumed

Movement

values:

Baud

Rate

1200,

Horizontal

Pitch

any

single width pitch (16, 12, 13.2, 16.5). Also assume that
horizontal tab stops are set at columns 9, 17, and 25 and
printing begins at column 9.
If the next two characters

received

are

characters

TAB

TAB,

required

First,
calculate the
following formula.
Final

Column

5.5

allow
ms

5.5 ms

per

Current

150

The

£ill

per

column

time

following

number

Then

calculate
the

Column

column

for

the

number of

fill

way.

columns

moved

using

Number

Columns

Moved

the

for

the

remaining

first

columns

and

columns.

183

required

Next,

divide
the
fill
execution time found in

183

time
Table

ms.
required
1-3.

the

character

Table

1-3

Character

Execution Times

Baud

Rate

Execution

Times

110

94 .0

300
600
1200

33.3
16.6
8.3

1800

5.5

2400

4.1

9600

1.0

4800

(msec)

2.0

NOTE:\n\nCharacter
fill times only.

execution

times

are

provided

for

calculation

Number

Fill

Characters

The

number

fill

this

muber

off

Twenty
two

three

characters

the
f£ill

183

8.3

required

whole

characters

Vertical
lines

(NUL)

per

inch

Baud

and

Rate

1200

baud,

paper

set

received

are

nine

characters

First,
calculate
the
following formula.
Number

Inches

actual

should
|

Moved

Lines

inches

Vertical

line

1¢.

line

distance

Round

23.

the

Pitch

Also

assume

feeds.

moved

using

the

Moved

Vertical

11/2

22.064.

which

Movement
values:

number,

tabs.

Assumed

the

(23)

Required

Pitch

9
6

Then

allow

for

the

200

2/6

266

The

f£ill

remaining

time

for

the

number

inches
=

304

required

divide
the
fill
execution time found in

The

fill

number

characters

fill

266

1/6

inch

moved

and

200

inches moved.

Next,

Number

first

304

time
Table

ms.
required
1-3.

required

characters

required

the

266

8.3

character

32.04.

Round

this number off to the next whole number, which
is
Thirty three (33) f£ill characters (NUL) should follow
nine line feeds.

33.
the

CHAPTER
CHARACTER

GENERAL

This

chapter

describes

terminals'

the

response

PROCESSING

received

characters. The terminal processes characters according to
American National Standards Institute (ANSI) standards X3.64-1979,
X3.4-1977 and X3.41-1977. The ANSI system defines the American
National Standard Code for Information Interchange (ASCII) chart
shown in Figure 2-1. Figure 2-1 shows each character with its
binary, octal, decimal, and hexadecimal values.

The terminal processes a received character based on the type of
by ANSI. The position of the character in the
character as defined

ASCII chart determines the type of character as either a printable
character

control

The ASCII

chart

character.

eight columns wide.

The control

characters

are

in columns zero and one. The rest of the chart contains printable
characters (except for SP and DEL). The DEL (delete) character is
always a control character. The SP can be considered either an
information

separator

control

character

printable

character.

A character sent from the computer to the first goes through the
application program,
then through the terminal handler of the
computer, then through the character processor of the terminal,
then finally creates a terminal action.

To know exactly what action is caused
your application program you have to
following parts of
Application

by a
make

character sent from
sure that all
the

the system are set properly:

program

Transmitting part of

the terminal handler

Receiving part of the terminal
General terminal settings

To set the terminal,

refer to this book and the Operator Guide; to

set the terminal handler, refer to your operating system guide;
set the application program, refer to your application guide.

COLUMN

B4 B3 B2 B1|ROW

0
1

0 00 1|1

0ot 1)z

(XOFF) | 19
13

01o01]s5

ENQ 5

6
=

12
I'peca|

01 00/}a

01 1 018

(XON)

001 90]2

20
41

33
21

#
$

o
1

30
&1

49
31

’

@
A
B

c
D

E
F

101

102

106

69
70

107

|CAN | 2

(

110

1 oo01|e | HT

111

)

25
32

¥*

1 ¢ 1 01w

1t o1 1N

1T 10 0112

10
A

ESC 27

112

113

114

124

a
b

125

126

141

97
61

142

143

99
63

84
54

144

160

112

113

114

163

7
140
60

106

104

123

121

)

103

1 000/|8

6
120

122

BEL

o1 1 1|7

5
100

4
60

3
40

22
16

NUL

BITS

000010

162
72

116
73

164

145

165

166

wa|

150

101

146

116
74

127

130

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120

131

151

171

152

163

[

89
59

132

133

134

147

1ws|]
69

106
BA

107
68

154

118

{

167

170
78

121

172

122
74

173

123
78

12
C

’

s| =

M | 5]

135

93l

M | 400

111 0|14

136

110

1111

137

177

157

117

troa

)18

ESC

ASCII CHARACTER|

1€

3E
77

115

790

108
6C
156

156 |

174

124

}

175

176

111 DEL

125
7D

126
7E

127

33 | OCTAL
27 1 DECIMAL

‘

18 | HEX
MA-TIET

Figure

2-1

ASCII

Chart

——

117

102

161

100
64

‘

For

example:

from the
sent
terminal because
the terminal is not set for form handling, or because the terminal
handler is set to change form feed into multiple line feeds.

@14)
(octal
<character
A form feed control
application program may not be executed by the

escape

dollar

control

sign by the

A horizontal
spaces

not

@33)

may

changed

into

program

tab

(octal

@l11)

terminal

the

is set

paragraphs

describe

in the
into

both

may be changed
handler,

into

may

terminal.

uppercase characters.
printable

characters

and

characters.

PRINTABLE

CHARACTERS

terminal

characters

receives

the

following

character

paper

character

application

following

The

(octal

case characters may be changed

control

tab control

the

be executed because

Lower
The

character

terminal handler or the application program.

line

printable

buffer.

conditions

received

The

occur:

characters

for more

than

and

stores

the

right

margin,

each

are

printed when

one

30 ms

motion

overprint command

(except

underline)

the

greater

active

received

column

character

not

1is

incremented. The actual
code received, the font

printed

character
selected,

than

and

the

active

column

1is

printed depends on the character
and the character set selected.

CONTROL CHARACTERS

A control character is a single character control function used to
control
terminal operation.
Control characters are not printed.
When the LAl0@ receives a control character the terminal responds
by performing the action associated with the control character.

The

LAl190

responds

the

control

characters

listed

Table

2-1.

Table
2-1
also
1lists
each
control
character's
mnemonic,
and
function. All other control characters received by the terminal
cause

action.

NOTE:\n\nEach

mnemonic.

control

The mnemonic

function

1s an

listed

abbreviation of

this

chapter

the control

has

function

name.

ESCAPE

AND

Escape

and

controls

character

CONTROL

SEQUENCES

control

that

set.

are

sequences

not

These

provided

are

sequences

used

the

are

control

multiple

provide

additional

characters

character

the

control

fuctions that are not printed but are used to control the printing

Table

2-1

ANSI

Control

Characters

Octal

Name

Mnemonic

Code

Function

Null

NUL

o00

Used

EOT

204

End

Trans-

mission

as fill characters
Communication Chapter).

Used

ENQ

@05

Request

Bell

BEL

aga7

Sounds

Backspace

210

Moves
one

Horizontal

211

tab

Feed

Vertical

character

answerback

message.

Tab

audible
the

@12

active

tone.

column

left

horizontal

stop.

Advances

g13

bell

column.

Advances

Tab

Line

disconnect

enabled.

Enquiry

(See

carriage

to next line. Performs
return if enabled.

Advances

vertical

top margin

tab

stop.

Form

Feed

Carriage

214

Advances

g15

Returns

Return

Shift

Out

gl6

line

Switches

character

Shift

Cancel

@17

CAN

230

SUB

Immediately

B32

enabled.

printer

ends

any

control

any

control

Ssequence.

Immediately
escape

margin.

feed

set.

Switches to G@
character set.

escape

Substitute

left

Performs

ends

sequence.

Characters

received with errors are
replaced by SUB if enabled.
is printed as " ",
Escape

ESC

B33

Introduces

Delete

DEL

177

escape

operation (not
input buffer).

SUB

sequence.

stored

the

and processing of characters. Escape and control sequences are
defined in ANSI standards X3.41 1977 and X3.64 1979. Refer to
Appendix C for more detail on escape and control sequence
processing.

NOTE:\n\nIf an escape or control sequence is aborted in the middle
of the sequence, it is not clear what action the following

character will have. It 1s therefore recommended that any abort be
followed

sequence

ESC \

cancel control

(octal

033

character or

a no action escape

127).

For example: some operating systems echo CTL (control) C as T C.
The sequence ESC CTL C then becomes ESC T C which puts the
If this occurs the
in ANSI string processing mode.
terminal

<characters

printable

discards

terminal

(see

ANSI

string

processing). if the host does not send the cancel control
character. To recover from this mode, if the computer does not
send the cancel control character; enter and exit SET-UP for the

Letterwriter 1608, enter and exit SELF TEST for the Letterprinter
100.

Detailed Sequence Definitions

The following paragraphs describe in detail the escape and control

sequences

described

which

the

LAl@0 responds.

in the following order.

These

sequences

are

Line Feed New Line Mode
Auto Wraparound Mode
Density Select Mode
Pitch

Select Mode

Printer Character Set Designation
Font

Selection

Request Font Configuration
Report Font Configuration
Horizontal Pitch (Characters Per
Horizontal

Margins

Horizontal

Tabs

Vertical
Form

Pitch

(Lines Per

Inch)

Length

Vertical

Margins

Vertical

Tabs

Active Column and Active
Product

Line

Identification

Line Feed New Line Mode -- defines the terminals' response to the
When this mode 1is off and the
line feed control character.
terminal receives a line feed control character, the terminal
When
increments the active line and advances the paper one line.
the
causes
character
control
feed
line
this mode is on, a received
1in
margin
1left
the
to
column
active
the
return
to
terminal
to
sequences
following
the
Use
functions.
usual
its
to
addition
enable or disable

line feed new line mode.

NOTE:\n\nCarriage return line feed mode is operator
only. Refer to the Operator Guide for more detail.
Name

Line
new

feed
line

Mnemonic

Sequence

LNM

ESC
P33

mode

Auto

Wraparound

printed

Mode

Function

[
133

Set

P62

P60

150

line

ESC

[

Set

@33

133

P62

P60

154

selectable

determines

line

feed

mode

new

on.

line feed new
line mode off.

where

the

character

when received while the active position is greater than
the right margin. When this mode is off,
any characters received
while the active position is at the right margin are not printed.

When

this

position

mode

on,

greater

any

than

characters

the

right

received

margin

the left margin on the next line.
Use
enable or disable auto wraparound mode.
Name
Auto

Mnemonic
wrap

are

the

following

Sequence

DECAWM

around

while

the

printed

active

starting

sequences

Function

ESC

[

Set

auto

@33

133

@77

067

150

mode

on.

ESC

P33

133

@077

067

1
154

Set auto wraparound
mode off.

mode

wraparound

Quality

Select
Mode
-determines
if
received
characters
are
printed
in
letter
mode
(medium
or
high
density,
depending
on
character ROM)
or draft mode. See Figure 2-2 for examples.
The
standard
DPSs
are
designed
to
print
in
draft
mode
(7
X
9
character)
or letter mode/high density
(33 X 18
character).
Some
of the optional DPSs are designed to print
in draft mode
(7 X 9
character)
or
1letter
mode/medium
density
(33
X
9
character).
Selecting letter mode selects either 33 X 18 or 33 X 9 characters,
depending on the DPS selected.
NOTE:

Medi
andum
high

density

terminal.

DPSs

can

both

resident

the

The

terminal
only
responds
to
these
sequences
when
the
AUTO/MAN
is in the automatic (up)
position. When the AUTO/MAN key 1s 1in
the
down
position
and
the
LTR/DRAFT
key
1s
used
to
select
the
print quality, any quality select sequence sent to the terminal is

key

processed

AUTO/MAN

Use

the

Name

Quality
select

and

key

stored.

set

following

The

the

sequences

Mnemonic

sequences

automatic

are

(up)

change

the

Sequence

performed

quality

select

the

feature.

Function

ESC

[

Set

P33

133

060

@42

172

mode

quality
to

(draft

when

position.

select

default

mode)
.

"RSAET (I A+, -, /01234546789 =xTRARCOREFGHIIKLMNGPGRSTUVHXYZINI
T “abode
FHUE (A4, -, /01234567892 ;<= 7@ARCIEFGH IJKLHNDPORSTUVHXYZIN]I"_
‘abedef
HER (D Ah+, =~ /0123456789 ;<= 7GARCIEFGH IJKLMNOPORSTUVWXYZLNI"
“abcdefq

DRAFT MODE

PUa#SEE' () *+,-. /0123456789 ;<=>?@ABCDEFCGHIJKLMNOFQRETUVREYZC
NI _‘abecd

THSRE () %+ ,-. /0123456782 ;<{=;PEABCDEFGHISKLMNOPQRSTUVRXYZL\J"_‘abcde
3G

() *+,-. /0123456789 ,;<=)?PBABCDEFCGHIJKLMNOPQRSTUVRIYZL\]1"_‘abcdef
SE& () *+,-, /0123456789 ; (= ?EABCDEFGHIJKLMNCOFORETUVRYEYZL v 1"_'abedefy

LETTER MODE (MEDIUM DENSITY)

L UH#SR& ' () %+ ,-./0123456789:; {=)>7?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[C\1"~_‘abc

"#S%&' ()*+,-./0123456789:; (=>?C@ABCDEFGHIJKLMNOPQRSTUVHWXYZL\]1~_'abcd
#SX&' ()*+,-./0123456789:;<(=>7?@ABCDEFGHIJKLMNOPQRSTUVWXYZL[\1"_‘abcde
SX&'()4+,-,/0123456789:;<=>?@ABCDEFGHIJRLMNOPQRSTUVWNXYZL\1"_‘abcdef
LETTER MODE (HIGH DENSITY)
MA-B300

Figure

2-2

Character

Density

Examples

Quality

Esc‘[

select

@33

A61

@42

172

133

~Set quality select
mode

draft

mode.

Quality
select

ESC
@33

[
133

2
@62

"
P42

Z
172

Set quality select
mode to letter mode
(medium

Quality

ESC
@33

select

[

Set

133

P63

P42

172

mode

quality select
to letter mode

(high

Pitch

Select Mode

terminal
is set
eight horizontal
the

terminal

selects

font

pitches

all

density)
.

density).

pitches.

When

the

to all pitch the terminal can print any of the
pitch selections available.
This is usefull when
used

1line

printer

(with

draft

density

selected). When font pitch is selected, the terminal will print at
the single width pitch of the current font
(18 or 12 characters
per inch) or 1ts double width
(5 or 6 characters per inch) only.
This is useful when printing draft copies of future letter quality
documents because the draft quality copy will look like the letter
quality copy.
all pitch.
Name
Pitch

Use

the

following

Mnemonic

sequences

Sequence
ESC [
?

select
mode

@33

Pitch
select

select

pitch

Function
Set pitch

select
mode to font
pitches.

133

@77

0962

@71

150

ESC

[

Set

@33

133

@77

@62

071

154

mode

font

density
to

select

all

pitches.

Printer
Character
Set
Designation
-The
character
sets
are
usually language sets with some exceptions; the VT100 line drawing
set,
symbol,
etc.
The
character
sets
that
the
terminal
can
actually
print
depends
on
the
Dot
Pattern
Set
(DPS)
that
the
terminal
1is
wusing
and
the
character
set
selected.
If
the
DPS
currently
set

1is

used

wused.

character
used. The

contains

the

character

set

DPS

currently

used

the

set selected,
standard DPSs

ISO

USASCITI

Kingdom

DIGITAL

Finnish

DIGITAL

Norwegian/Danish

DIGITAL

Swedish

German

DIGITAL French
ISO French
IS0 Italian

IS0

Canadian

Spanish

DIGITAL

VT100

does

that

not

character

contain

the default character set for that DPS
contain the following character sets:

ISO

United

selected,

line

drawing
22

set

the

1is

Four

these

character
two are

only).

are

‘sequence.

two

and

the

control

character sets.
selects
the
GO
control

(remains

1locking

Once

single

sets

locking

nonlocking

The

computer

character

sets

preselected

active

character

using

character

The shift
character

character

can

(remains

selects

the

sets

for

one

sets

are

select

are

used

(designated).

until

character

designated

character

switch

Two

command),

printable

designated

set

the

between

the

(SCS)

computer,

the

active

in
(SI,
octal 017)
control character
set.
The
shift
out
(SO,
octal
@16)
the

character

set.

The
designated
character
sets
are
used
until
another
select
character set (SCS) sequence is received. The G@ and Gl character

sets

can

character

redesignated

set

(SCS)

sequence

the

often

computer
as

needed.

using

the

select

The sequence used
to designate the G@ character set 1is ESC
(
(octal 033 050), followed by a valid final character. The sequence
used

designate
the

character

followed

by a valid

final

The

nonlocking

character

two

set

ESC

)

(octal

933

@51),

using

character.
sets

are

designated

and

the select character set (SCS) sequence. The G2 and G3 character
sets are activated
for only one character at a time.
They are

activated

using

the

single

shift

(ESC N)

(octal

and single shift 3
(ESC 0)
(octal ©#33 116)
for G3
terminal
returns
to the previously used character
single character is printed.
The

sequence

used

designate

the

character

#33

115)

for G2

sequences.
set after

set

1is

The
the

ESC

(octal @033 ©952), followed by a valid final character. The sequence
used to designate the G3 character set is ESC + (octal @033 @53),
followed by a valid final character.

Table
valid

2-2 lists the currently
final characters.

Font Selection -fonts
or
styles.

character

but

character

sets

and

their

The
LAl0@@®
can
print characters
in
different
Changing
a
font
changes
the
shape
of
the

does

currently provides

available

not

the

change

the

following

character

itself.

Digital

fonts:

Courier

Gothic
Orator

Symbols

Additional fonts will be available in the future. The terminal
contain
up
to
five
fonts
accessible
at
a given
time.
If

multiple
these

the

font

option

sequences

operator

when

forces

installed,

the

font

option

from

the

set

terminal
to

the multiple

only

computer

select.

responds

select.

font option

select sequences sent to the terminal are processed
The sequences are performed when the option
is set

can
the

any

When

font

and stored.
to computer

Character Set Final Characters

Table 2-2

Character

ISO

Set

United

Final

Kingdom

USASCII

DIGITAL

Character

A
1901

B
102

Finnish

5
@365

DIGITAL Norwegian/Danish

6
66

DIGITAL

Swedish

7
267

ISO German

DIGITAL

French

K
113

Canadian

9
071

ISO

French

122

DIGITAL VT100

drawing
ISO

set

Italian

line

@60
Y
131

ISO

Spanish

Z
132

This

sequence
1is
also
used
to
set
or
clear
the
underline
attribute. This feature is used to underline characters. Use the
following sequences to select a font or the underline attribute.

NOTE:\n\nIf the selected font
selects the default (font 1).
Name

Mnemonic

not

installed,

Sequence

Font

ESC

Font

select

the

terminal

Function

[

Select

ESC

[

Clear

@33

133

@60

155

Font
select

ESC
@33

[
1
Y
m
133 061 @60 155

Select

Font

Font
select

ESC
P33

[
1
1
m
133 @61 @61 155

Select

Font

Font
select

ESC
@33

[
133

1
@61

2
m
@62 155

Select

Font

Font
select

ESC
@33

[
133

1
@61

3
m
P63 155

Select

Font

ESC

[

Select

Font

select

@33

133

@61

@64

155

select

P33

133

P64

155

underline
underline

Request Font Configuration -- causes the terminal to send the font
font
configuration
report
to
the
computer.
Send
the
following

sequence

the

LAl@0

request

Request

ESC

Font
Configuration

@33

[
133

font

?
077

1
@61

configuration.
0

060

143

Causes

LAl@0@ to send
font configuration
report
ESC [ 2 Pn ; Pn SP D
once

for

each

installed
NOTE:

Report

represents

Font

the

each

font

space

Configuration

configuration

for

the

request

installed

selection

with

font.

code.

character
the

the

The

One

Selection

Font

Font
Font

4
5

13
14

Code

ESC
code

0440).

responds

the

[

parameter

selection

font.
Font

terminal

sequence

first

(octal

font.

;

the

font

D once

sequence

available

for

1is

each

NOTE:\n\nFont selection code 10 is always present
It therefore indicates the end of the report.

and

The

font

second parameter
indicates the font
indicates the following information.
Font

128
-

the

The

last.

type

200

density

font

density

font

custom

font

code

the USASCII and
an
even
number
character sets.

United

font

odd

number

less

than

127,

the

font

contains

United Kingdom character sets. If the font code is
less
than
128,
the
font
contains
the
following

Kingdom

USASCII

Finnish

Norwegian/Danish
Swedish
German

French

Canadian

French
Italian

Spanish
VT100

this

Font

code

Indicates:

129

Code

type.

sent

line

time

drawing

the

Code

set

currently
Font

assigned

font

codes

are:

Type

@3
77
11

Gothic 12, US and UK character sets
Courier 12, US and UK character sets
Symbol 1@, US and UK character sets

Courier

g6
?9

Courier 10, standard
Orator 1M, US and UK

NOTE:\n\nRefer

the

ROM

10,

Option

and

character
overlay
character

Documentation

for

sets
sets

codes.

Horizontal

Pitch

determines

the

spacing.

(Figure

The

(Characters

width

terminal

Any

2-3).

line.

Per

printed

has

eight

Horizontal

pitch

characters

Inch)

their

horizontal

pitch

well

selections

a single

combinations of pitch may be used on

NOTE:\n\nThe actual horizontal pitch used by the terminal depends
on the density select mode, pitch select mode and horizontal pitch

r features when attempting to select
to all three
features. Refe

horizontal

Changing
modified

pitch.

the horizontal pitch modifies
new active column is the first

the
active column.
The
column boundary at or to

the right of the physical position of the previous active column
in the old pitch. New active column is calculated in the following

way.

(01d column New

column

The

X New pitch

0ld

where

pitch

New column
New pitch
0ld column

=
=
=

the new active column
the new pitch in inches
the old active column

0ld pitch

the old

division performed

fractional

part of

above

the quotient

pitch

per

character

inches per character

integer division.

Any

remainder

is discarded.

Changing horizontal pitch also clears horizontal margins. The left
margin is set to column one and the right margin is set to the
maximum column for the selected pitch (Table 2-3).
The

horizontal

(char/in).

The

pitch

default

following

selection

sequences

are

used

characters

set

per

inch

horizontal

pitch.

Name
Set

horizontal
pitch

Mnemonic
DECSHORP

Sequence
ESC [
@

Function
Set horizontal

P33

133

066

167

ESC
@33
ESC
@33

[
133
[
133

1
W
061 167
2
W
@862 167

pitch

char/in

Set horizontal
to 10 char/in
Set horizontal
to 12 char/in

pitch
pitch

DHAaRAODTERS

CHARACTERS

&H.6

CHARACTERS

8.25

CHARACTERS

CHAKACTERS

PER

12 CHARACTERS PER

INCH

3.2 CHARACTERS PER

INCH

2-3

O OLNCH

FER

PER

INCH

16.5 CHARACTERS
PER INCH

Figure

PER

MA-B323

Horizontal

Pitch Examples

W
3
ESC [
@33 133 063 167

Set horizontal pitch
to 13.2 char/in

ESC
@33

w
4
[
133 064 167

Set horizontal pitch
to 16.5 char/in

ESC

[

@33

133

065

Set horizontal pitch

167

5 char/in

w
6
ESC [
@33 133 @66 167

Set horizontal pitch
to 6 char/in

W
7
ESC [
@33 133 867 1lo7

Set horizontal pitch
to 6.6 char/in

w
8
ESC [
@33 133 @70 167

Set horizontal pitch
to 8.25 char/in

Horizontal Margins -- The left horizontal margin specifies the
first printable column on a 1line; the right horizontal margin

specifies

the

column

printable

last

Printing

line.

1is

permitted only within the left and right margins inclusive (Figure
The set horizontal margins sequence when accompanied by two
parameters, sets the left and right margins. If both parameters

are not zero, and the first is the smaller of the two, the 1left

margin

set to

the

first specified parameter and

the

right

margin is set to the second. The carriage is then repositioned to
the new left margin.

the horizontal
NOTE:\n\nChanging the horizontal pitch modifies

margins. The left margin is set to column one and the right margin
is set to the maximum right margin in the selected horizontal
(Table

pitch

2-3).

The sequence is ignored if the first parameter 1is greater than the
second

parameter.

The

sequence

1is

also

1ignored

one

the

specified parameters would set the right margin further right than
13.2

inches.

If the first parameter in the sequence is omitted, the remaining
parameter sets the right margin to the specified value. If an
attempt is made to set the right margin to the left of the left
margin,

the sequence is ignored.

If the second parameter in the sequence is omitted, the first
parameter sets the left margin to the specified value. If an
attempt is made to set the left margin to the right of the right

margin, the sequence is ignored. If the active column is less than

the new left margin,

it is set to

carriage is repositioned.

the new left margin and

the

RIGHT MARGIN

TAB SE

TTING

/
S

LEFT MARGIN

Figure

2-4

Horizontal Margins

and Tabs

Table 2-3
Horizontal
10

Maximum Right Margins
Pitch

Maximum Column
132

158
168
216
66

79
84
108

If both parameters are zero or omitted,

The

default

The

setting

following

Name

Set

left

and

right

for

the

sequence

the

right

left

margin

used

the margins are unchanged.

margin

column

set

the

left

column

one.

The

132.

and

right

Mnemonic

Sequence

DECSLRM

ESC

[

933

Set

133

***

@73

***

163

margins

margins.

Function

margins

left

values

and

right

to the
given

NOTE:\n\nThe *** character is used to indicate variable numeric
parameters within the octal representation of the control or
escape

sequence.

Horizontal Tabs -- A horizontal tab is a preselected point
on a
line
to
which
the
printe
head
advances
when
a
horizontal
tab
control
character
is
received
(Figure 2-4). The
LAl9@
has
217
possible horizontal tab stops, one for each column. Tab stops
are
associated
with
column
numbers,
not
physical
positions
on
the
paper.

Therefore,

physical

position

independently.
is

true

cleared

for

settings
The

changing

Setting

clearing
regardless

for

tab

horizontal

following

pitch

stop

may

also

already set has no
already cleared. Tab

margins

tabs

sequences

Each

stop

stop
of

horizontal

stops.

are

changes

set

horizontal

every nine columns.

used

set

pitch.

clear

The

Mnemonic

Sequence

Horizontal

Function

HTS

ESC
@33

Set horizontal
stop at active

tabulation
set

tab

column

Horizontal

DECHTS

tabulation

ESC

Set

B33

@61

stop

set

horizontal
at

tab

active

column

Tabulation

TBC

clear
Tabulation

TBC

clear

Tabulation

TBC

clear

Clear

default

horizontal

Name

H
110

cleared

effect; the same
stops may be set

one

stops.

the

All

horizontal
tabs

DECCAHT

ESC

[

)

Clear

@33

133

060

147

tab

ESC

Clear

@33

133

062

147

tab

active
all

column

horizontal

stops

ESC

[

Clear

B33

133

@63

147

tab

all

horizontal

stops

ESC

@33

Clear

062

tab

horizontal

all

stops

horizontal

NOTE:\n\nThe *** character is used to indicate variable numeric
parameters within the octal representation of the control or
escape

sequence.

DECSHTS

Set

ESC
@33

horizontal
tabs

[
Pn
133 ***x

H
@73

.es
,,.

PN
***

u
165

Set
horizontal
stops
given

tab
the

values

*Vertical

Pitch

Vertical

pitch

determines

the

spacing

between

lines, not the height of printed characters
(Figure 2-5). The
LA190@ has six vertical pitch selections. Changing vertical pitch
changes:

the active line. Causes the active line to
the next vertical motion command so that

between the top margin and the active line
the pitch selected.

multiple of

the action of

the

form

move down on
the distance

is an

integer

length command.

the action of set top and bottom margin commands.
the position of the last printed line on the form. The
last printed line will always be above the bottom margin.
the

position

* Note

that

DIGITAL

terminals.

Changing

vertical

the vertical

the

top of

the

form

vertical

pitch

pitch does

the

tabs.

feature

not

is different

affect:

reference.

length.

top margin.

The

the

same position.

the

bottom

margin.

first

The

below the bottom margin.

line will

last

line

always be

will

never

The vertical pitch default selection is six lines
following sequences are used to set vertical pitch.
Name
Set
vertical
pitch

from previous

Mnemonic
DECVERP

per

printed

inch.

The

Sequence
z
Y
ESC [
@33 133 060 172

Function
Set vertical pitch to
six lines per 1inch

ESC
@33

Set vertical pitch
six lines per inch

[
133

1
@61

z
172

2 LPI

$ELE (2 kb, -

3LPI

4 LPI

KX174
2X 0T

6 LPI

Creero

LUESLE

AA R

"ESLR

DA+

8 LPI
(A

S WO

FEAR
O A+,

D TEEUR

& 25IR

$%LC
() A+

CESUR
$F$UR

()(A A+

¥4787 Ok+,

v X (Y +,?’”?‘
A+,

LR
A+,
-,
B
A,

74 R GF TINEN

$FSAR

OVA+,

SUR
O k+,~

(YA+,~.70

Figure

2-5

Vertical

O k+,-./

Pitch

Examples

ESC
@33
ESC

[
2
z
133 062 172

Set vertical pitch to
eight lines per inch

@33

133

[

Set vertical

pitch

ESC
@33

[
133

4
064

z
172

Set vertical pitch
two lines per inch

ESC

[

Set vertical

@33

133 065

172

three lines per

ESC

[

Set vertical

@33

133

066

172

four

@63

172

twelve

lines per

inch

pitch

inch

pitch

lines per

inch

*Form Length -- The LAl@#@ can operate in one of two modes: form
mode or no form mode (roll paper). In the no form mode, there is

no form length or vertical
lines being
*

Note

DIGITAL

margins,

spaced appart according

that

the

form

length

printing

occurs

continuously,

the current pitch.

feature

different

from

terminals.

When
in form mode,
the terminal will
not print above
the
top
margin or below the bottom margins, and lines will be spaced so
that the distance between active line and top margin is always a

(Figure 2-6).

multiple of the current pitch.

When a form length of zero is defined for the terminal, the LAl00®
assumes that roll paper is being used and enters the no form mode,
When a non zero form length is given, the terminal assumes that
form paper is being used, and enters the form mode.

The form length is measured in lines 1/24 of an inch. The form
length can be no longer than 21 inches. To set form length, first
try to ensure that the terminal is at the top of form.
NOTE :\n\nRemember

top margin,

top margin must

Measure
current

the

form

cleared.

feed

puts

the

pitch,

set

multiple

the

form

this

1length

new vertical

active

pitch.
not

that
that

the

multiple

default
sets

form
form

length

the

know
the
new form

the

vertical

pitch

1is

pitch.

and all

Then, send the form length command with the parameter
form length multiplied by the current vertical pitch.

sequence

form the

you
the

current

NOTE:\n\nMost form lengths are a multiple of 1/12,
form lengths are either a multiple of 1/12 or 1/8.

The

line

To advance to the top of

the
form
1length
in
inches.
Ensure
vertical
pitch of
the
terminal
and

length

unknown

that

not the top of form.

selection

length.
35

1is

inches.

equal

The

allowed

the

following

X |e

o 1234567890abcdefghij

]

1/3 m_I °

-a -

T -G

1234567890abcdefghij.

1234567890abcdefghij
1234567890abcdefghij
1234567890abcdefghij

- E

MARGIN

1234567890abcdefghij

1234567890abcdefghij
———UNUSED

1234567890abcdefghij

AREELEEE-ELE
N o

L+

BOTTOM

1234567890abcdefghij

—X < 1234567890abcdefghij

1/2 in.

o
.

——F 1° 1934567890abcdefghij

1/2in. |

3 1pi TO 2 Ipi

LIV
i

1/3 En‘" °

TOP MARGIN

oilooo oo

o
£

Qf@GQQQQQQQQQQGQQ o

2 Ipi

=== == ===
R====

TOP OF FORM —

c0c0c0006000
0o

FORM

NOTE:

ALWAYS START PRINTING AT TOP MARGIN OR AT SOME DISTANCE FROM TOP MARGIN THAT IS A MULTIPLE OF THE
CURRENT VERTICAL PITCH. NEVER PRINT BELOW BOTTOM MARGIN.

NO FORM
3 Ipi
1234567890abcdefghij

31pi TO 2 Ipi

1/3 m.,

1234567890abcdefghij

1234567890abcdefghij
1234567890abcdefghij

Lol

1234567890abcdefghij

e IRt§

2 lpi
1234567890abcdefghij

1234567890abcdefghij
1234567890abcdefghij

1/2 in.
1234567890abcdefghij

1234567890abcdefghij

1/2 in.

1234567890abcdefghij

1/2 in.
1234567890abcdefghij

1234567890abcdefghij

1234567890abcdefghij
1234567890abcdefghij

NOTE:

ALWAYS PRINT LINES EVENLY ACCORDING TO VERTICAL PITCH,

Figure

2-6

Form/No

Form Mode

MA-B388

Sequence
Pn
ESC [
@33 133 ***

Mnemonic
Name
DECSLPP
Set lines
per physical
page

Function
Set form 1eggth to n
X pitch in inches,
set top margin to 0

t
164

active line

inches,

to line one, set top
of form to current
position, and a set

form

bottom margin to

length.

NOTE :\n\nThe *** character is used to indicate variable numeric
parameters within the octal representation of the control or
escape

sequence.

Vertical Margins -- The top vertical margin specifies the first
printable line; the bottom vertical margin specifies the limit for
the last printable line (Figure 2-8). Printing is allowed only on
the lines between the top and bottom margins (including the top

margin).

The

vertical

bottom margin

may

pitch.

not

included

depending

the

To set the top and bottom margins, first be sure that the distance
between the top of form and the desired margin is a multiple of
the vertical pitch selected. Otherwise, change the pitch and then
send the set margin command with a parameter equal to the desired

margin in inches multiplied by the current vertical pitch in lines
per

inch.

Attempting
to print above
the
top margin or below
the
bottom
margin automatically advances the active line to the top margin of
the next page.
For example,
a
line
feed
(LF)
received at the
bottom margin causes the terminal to perform a form feed.
The
set

set vertical
the top and

and the

first

margins sequence, accompanied by two parameters,
bottom margins. If both parameters are not zero

the

smaller

the

two,

the

top margin

set

than

the first parameter and the bottom is set to the second. Then the
paper may be repositioned to the new top margin depending on the
current line position and terminal activity.

The

sequence

the

equal

specified

assigned

ignored

form

the

parameters

length.

first parameter

parameter

the second parameter.

sets

the

bottom

first parameter

The sequence

would

the

set

sequence

margin

the

is greater

is also

ignored

omitted,

the

bottom

margin

specified

if one

past

remaining

line.

attempt is made to set the bottom margin above the top margin,
sequence

ignored.

the

second

parameter

parameter
in
the
sequence
is
top margin to the specified

sets

omitted,
line. If

the

the
first
an attempt

is
made
sequence

to
set
the
top
margin
below
the
bottom
margin,
is ignored.
If the active line is less than the new
margin,
it
1is
set
to
the
new
top
margin
and
the
paper
repositioned.

top
is

If
both parameters
are
unchanged.
The default

are
The

default
The

selection

following

Name

Set

top,

for

set
to
zero
or
omitted
the margins
top margin selection is top of form.
the bottom margin is 11 inches.

sequences

set

the

top

and

bottom margins.

Mnemonic

Sequence

DECSTBM

ESC

P33

133

***

(73

***

162

bottom
margins

Function

Set

top margin

to line Pn and
bottom margin to
line

NOTE:\n\nThe
parameters
escape

the

octal

used

indicate

representation

variable

the

preselected

line

numeric

control

sequence,

Vertical
print

*** character

withln

the

Tabs

head

received

-- A vertical

advances

(Figure

positions.

tab

when

2-7).

vertical

The

tab

terminal

control

has

168

which

the

character

vertical

tab

Vertical tabs may be set and cleared like horizontal
tabs.
Vertical
tab
stops
are
associated
with
specific
1line
numbers, not physical positions on the paper. Therefore, changing

vertical
the

pitch

paper.

line.

The

168

inches

lines

the

default

following

NOTE:\n\n2l

first

changes

The

printing

settings

sequences

set

tab

set

lines.

Only

stops.

233

DECVTS

stops.

inch

ESC J

Vertical

tab

Sequence

set

vertical

per

Mnemonic

tab

one

lines

VTS

tabs

are

vertical

Vertical

vertical

tabs

clear

Name

vertical

can have

position

for

252

every

the

Function

Set vertical

112

tab stop at
active line

ESC

Same

@33

063

NOTE:\n\nThe *** character is used to indicate variable numeric
parameters within the octal representation of the control or
escape

sequence.

Name

Mnemonic

Sequence

Set

DECSVTS

ESC

[

@33

133

***

@73

vertical
tab

stops

Function

ees

Set

vertical

***

166

tab

stops

lines

given

(=]

[«]

-fl
o

[+
o

-2

INCHES 1 o
3

wrior)

SiX

-t MHOFQRETY

PER

NOFORS TUVKX

[ LINES )
|

KLMNOPORSTY

‘

lsnoparsTuvkd

MA-TT13A

Figure

2-7

Vertical Features

Tabulation

TBC

ESC
@33

clear

[
133

1
@6l

g
147

Clear
vertical
stop

active

Tabulation

TBC

clear

tab

line

ESC

[

Clear

@33

133

964

147

vertical

all
tab

stops

Clear

All

DECCAVT

vertical

ESC

#33

@64

Same

tabs

Active Column
the

and

Active

character

will

Line
be

Active

printed.

column

Active

line

the
is

column

the

the next character is printed. Column and line numbers
one,
not zero.
Printable characters usually increment

column.
Line
active line.

feeds,

vertical

tabs,

and

form

feeds

where

line

where

begin with
the active

increment

the

The active column and active line are collectively known as active
position. Active position is only loosely linked to the physical
position of the carriage and paper mechanism.

When

auto

last

moves

inches

one

second.

character
to

This

the

view

right

action

selected,

whenever

allows

the

printing
last

terminal

stops

character

viewed.

carriage
more

printed

However
active
column
is
not
affected
by
this
characters do not have an active position attribute.

Bell
not

for

guaranteed

sounded

any

particular

Name
Index

escape

sequences

modify

active

feature.
They are

position.

In addition to the control characters (backspace,
carriage
return,
1line
feed,
vertical
tab,
and
following

than
to

column

horizontal
form
feed)

and

active

tab,

the

line.

Mnemonic

Sequence

Function

IND

ESC

933

104

Increment active line
and advance paper -line feed new line mode

has no effect
feature

this

NOTE :\n\nThe *** character is used to indicate variable numeric
parameters within the octal representation of the control
or
escape

sequence,

Vertical
position

VPA

ESC
@33

[
133

Pn
***

absolute

d
144

Set active line to Pnif Pn is less than or
equal to active line,
or

greater

bottom margin,
line is set to
margin on next

than
active
top
page

line

Horizontal
position

NEL

HPA

ESC

@33

105

Set active column to
left margin and
increment active line

ESC

@33

133

***

149

absolute

Set active column
to column Pn -- if Pn
is greater than right
margin, active column
is set to left margin

on
is
to

next line -less than or
left margin,

column

set

if Pn
equal
active

left

margin
Horizontal
position
relative

HPR

ESC

[

@33

133

**%

Advance

141

of
--

actual value of
1f Pn = @, then

motion
Cursor

Cuu

ESC

[

P33

133

***

101

current

active column by Pn
columns -- if active
column exceeds right
margin, active column
is set to left margin
on next line regardless
Pn
no

occurs

Decrement

current

active line by Pn lines
without going past top
~margin -- if Pn is
greater

than

equal

to current active line,
sequence 1is ignored

Vertical
position
relative

VPR

ESC
G333

[
133

Pn
**%

145

Advance active line by
Pn lines -- if Pn = @,
256 lines is assumed,
if parameter exceeds
bottom margin, active
line is set to top
margin on next page
regardless of actual
value

NOTE :\n\nThe PLD sequence does not modify active line. To avoid
losing the top of form reference send an equal number of PLU
sequences to the terminal.
Partial
line down

PLD

ESC

P33

113

Index paper up .212
cm (1/12 inch) -- 1line
feed new line mode has
no effect on this
sequence

NOTE:\n\nThe PLU sequence does not modify active
losing the top of form reference, send an equal
sequences to the terminal.
Partial

line

PLU

ESC
P33

L
114

line. To avoid
number of PLD

Index paper down .212
cm (1/12 inch) =-- 1line

feed

new

line

effect

mode

has

this

sequence

Reverse

index

ESC

Decrement

@33

115

and

move

line

active

paper

line

down

feed

line mode has no
on this sequence

Product

Identification

The

LAl@@

automatically

one

new

effect

transmits

answer to the ANSI standard request for device attributes.
The
following sequences cause the terminal to transmit 1its product
identification sequence.
Name
Device
attributes

Mnemonic
DA

Sequence
ESC |
C
@33 133 143

Function
Transmits
ESC [ 21 @ ¢
which forms the

product
identification

the

basic

LA1Q@.

Device
attributes

ESC
33

[
133

*Identify

DECID

ESC

@33

132

terminal

* This sequence

is provided

]
960@

for compatibility with previous

It may not be supported

therefore

not

CONTROL

When

the

Same

products.

ANSI

C
143

in future products and

1is

recommended.
STRINGS

terminal

receives

any

the

escape

sequences

1listed

below, it responds as usual to control characters received (octal
pP@ -- 937 and 177) and discards any printable characters received

when

(octal

040

one

the

176).

The

following

terminal

occur.

is received.
(substitute),

received
an

reverts

conditions

text

processing mode

ESC

(escape)
V

occurs.

1is

Name

Mnemonic

Sequence

Application
program
command

APC

ESC
@33

137

Operating

0SC

ESC
@33

]
135

ESC ~

system
command

Privacy
message
Device

DCS

@33

136

ESC

@33 120

control

NOTE:\n\nThe LAl0¢ remains in DCS mode until it recognizes a valid
protocol selector, or the terminal receives the terminator
sequence ESC \. For more detail on DCS mode refer to the Graphics
Mode and Answerback Message sections 1n this chapter.

GRAPHICS MODE

While

text mode,

dots

graphics

mode,

characters

printed.

are printed

received

Graphics

mode

allows

combinations anywhere on
pictures and plot graphs

a page. This
(Figure 2-8).

After

mode,

pitch,

margins

entering

graphics

the

and horizontal margins change.
section describes

define
mode

they

are

received.

specific

columns

users

dot

can

used

draw

vertical

pitch,

horizontal

The graphics mode pitch

and

these changes.

DIGITAL does not recommend using single
paper when operating in graphics mode.

sheet

tractor
|

feed

The terminal has a horizontal resolution of 132 columns per inch
with a 50 percent overlap, and a vertical resolution of 72 dots
per inch with no overlap between dots.
There is a 44 percent dot
overlap between lines.
The aspect ratio (ratio of horizontal to
vertical resolution) 1is 1.83.
GRAPHICS

STRING

FORMAT

The format for a string of graphics data is as follows.
DCS

introducer

Protocol

Data

ESC

selector

DCS terminator
DCS

INTRODUCER

and

waits

Pn g

Control characters or column definitions
ESC \

when the terminal receives the DCS introducer,
for

the

correct

protocol

selector.

is the ANSI DCS introducer sequence ESC P

DCS

introducer

(octal 033 129).

When the protocol selector is received the
process data as described in the data section.
43

it enters DCS mode
The

terminal

begins

"Vd*el

a““‘

EXPENDITURES

FURLIC AAD PRIERTE SXHMRE
S

ENROLLMENT

BILLIONS OF DOLLARS

KHILLIONS

100

109
Errollment,

7% |-

total

7 Public EnrolIlment :}— Right Scale
R Private Enroliment

— Total Expenditures
--»- Public Expenditures

Left Scale

- Pravate Expenditures

- 50

| #

- 25

|
1972

1974
MA B389

Figure

2-8

Graphics

Capabilities
e

The

terminal

is not
out of

remains

DCS

mode

the

proper

protocol

selector

received, or if the terminal receives a character that is
range before the correct protocol selector
is recognized.

PROTOCOL

SELECTOR

After receiving the DCS 1ntroducer, the protocol selector causes
the terminal to enter graphics mode. The protocol selector for the
terminal consists of a numeric parameter and a final character.
The correct protocol selector is 1 (octal @061) and g (octal 161).
Valid

protocol

selectors

include:

selects

default graphics protocol

selects

DECwriter

255

reserved

IV protocol

for

(same as

(described

for
this

LAl10%)
section)

future development.

DATA

The data contained within a graphics string can either be control
characters or printable data.
The following paragraphs describe

the

control

mode,

characters

which

the

terminal

responds

and the format of the printable characters received.

Control

Characters

In graphics mode,

the

terminal

responds

the

graphics

following

control

characters.

ANSI Control Characters
Table 2-4 lists and describes the
in
the
@08
to
037 octal
range
graphics mode.

Private

Control

ANSI control characters
that are processed
1in

Characters

Table
2-5
1lists
and
describes
the
private
control
characters
in
the
0404
-@076
octal
range
that
are
processed in graphics mode.
Printable

Data

After the proper protocol selector
1is received,
any
received in the @77 -- 176 octal range 1is considered

character
printable

data. These characters define a column of six dots to be printed.
This

allows

(Figure

not

used

2-9).
in

Printable

of fset

printhead
is

The

set

firing

seventh,

graphics mode.

characters

(octal

character
bit

selective

@77)

received.

wire
to

1is

are

The

result
and

dot

from

is a

six

top

ninth

the

dot

printed,

six

printhead

wires

printhead

wires

are

following

way.

The

binary

column
if

the

value

the

definition.

corresponding

one.

The least significant bit is
wire
(wire one).
The sixth

printhead wire,

mode.

and

processed

subtracted

fired,

the

eighth

and

is the

associated with the top printhead
bit 1s associated with the sixth
last wire that can be fired in graphics

Table

2-4

Graphics

ANSI

Control

Characters

Name

Mnemonic

Octal
Code

Cancel

CAN

@30

Immediately
graphics.

Substitute

SUB

@332

Replaces any character received
with errors.
When received in

Function

graphics,
one
Escape

ESC

233

SUB

column

Causes

the

graphics

causes

exit

processed

space.
terminal

and

process

exit

the

sequence.

NOTE :\n\nNUL,

text mode

EOT,

(refer

ENQ,

BEL,

to Table 2-1).

DEL,

SI,

and

are

BS, LF, CR,'FF, HT, and VT are ignored in graphics.

processed

Table 2-5

Graphics Private Control Characters
Octal

ASCII

Character

Function

DECGRI

p41

Begin repeat sequence

DECGCR

g44

Returns to graphics
left margin

DECGNL

@55

Returns to graphics

Name

Mnemonic

Graphics

Code

Repeat

Introducer

Graphics
Carriage
Return

Graphics

New Line

left margin and and

~advances

graphics

line

Figure

2-9

COU~
MNP Wy

BOTTOM

000000000

WIRE

TOP

BIT 1
BIT 2

BIT3

BIT 4
BITS
BIT6

NOT USED
NOT USED
NOT USED

Graphics

Printhead

Use
RNy

ve
AU bW

W+~
YUt

Top

Wire

Not

used

Not

used

Bottom

Not

used

Refer

Repeat

Sequence

Table

2-6

for

several

printable

character

examples.

A repeat sequence allows the terminal to continually print a dot
column for a specified number of times.
It has the same effect as

receiving

the

defined

follows.

dot

column

Repeat introducer
Numeric parameter
Dot

column

The

repeat

(octal

sequence

that

many

times.

repeat

sequence

1is

!
(octal 041)
Number
of
times
to
print
the
(characters in the octal range of
Character in the @77 -- 176 octal

dot
column
068 - @71)
range

introducer

character

the

private

control

@41).

The numeric parameter specifies the number of times to print the
column definition that follows. The numeric parameter 1s a string
of
characters
in
the
@60
-@71
octal
range.
If
a
numeric
parameter is not specified,
a value of zero is assumed for the
numeric
parameter.
If
the
wvalue
specified
1is
larger
than
the

graphic printer limit for numeric parameters (64 K), the limit
assumed. All decimal digits are processed as part of the count.

1is

The

1is

dot

printed
All

column

character

as many times

control

the

@977

specified

characters

received

during

usual.

example,

the

processed

the

repeat

sequence

All

unspecified

DCS

Terminator

For

by the

176

numeric
a

octal

repeat

control

range)

parameter

count.

sequence

character

are

resets

count.

characters

(octal

@872

076)

are

ignored.

The DCS terminator ESC \ (octal @33 134) causes the- terminal to
exit graphics mode and revert to text mode character processing.
The CAN (cancel) or ESC (escape) control characters also cause the
terminal to exit graphics mode.
If the ESC control character 1s

terminal

received,

the

sequence.

escape

exits

graphics mode

and

starts

processing

Table

2-6

Character

Printable Character

Octal Value

Binary Value
(minus

077

Examples

Wires

Offset)

0e000000

o
o

O
O
O
O

100

0P0B0001

*
O
O
O
O

176

P3111111

*
*

137

00100000

o
O

O
O
O
*

Fired

After an exit graphics, the terminal is set to the following:
Text mode features (margins, pitch) are restored

Vertical

position

the

control

just before

entering

according

modified

characters received while in graphics mode

position

Horizontal

graphics mode

the

same as

The first text mode vertical motion command causes the
terminal to advance to the next text mode line before
executing the command.

GRAPHICS MODE PITCH

In graphic mode
inch

the horizontal

(9.5 characters per inch).

lines per

pitch

set

132

columns

per

The vertical pitch is set to 1/12

inch.

GRAPHICS MODE MARGINS

Graphics mode maximum line length depends on the horizontal pitch
and the margins selected in text mode. In graphics mode, the

maximum line 1length is 13.1 inches (1,736 dots). To use the
maximum line length, the following conditions must be met before
entering graphics mode.

the

inch

actual

horizontal

(depends

density selection).

pitch

must

setting,

pitch

characters

mode,

and

per

the

Text mode left margin must be set to column one

Text mode right margin must be set to column 132
Active column must be column one

After entering graphics mode the left margin is repositioned to
the right .11 inches maximum of the last printed column in text
mode. Graphics mode left margin is calculated as follows:
Left Margin =

(Current Active Column - 1)

X 0ld Pitch

If there is a remainder, round up to the next whole number.
After

entering graphics mode

the

right margin

the left of the text mode right margin

repositioned

(.11 inches maximum).

graphics mode right margin is calculated as follows:
01ld Right Margin X 0ld Pitch
Right Margin =

Discard

any

remainder.
51

The

attempt

responds

made

according

the

auto

past

the

right

wraparound

Superscript or
subscript
can
be
used
to
mode comments.
Reverse line feed is

the

graphics

mode

vertical

ANSWERBACK

MESSAGE

Answerback

1is
a

the

terminal

pitch

may

not

pitch.

ENTRY
message

for

the

thirty

computer.

This

the

terminal

selection.

label
grahic
data
with
not recommended because

text

mode

margin,

mode

the

same

characters

message

that

the

text

identifies

transmitted

upon
request from the computer,
the keyboard
(Letterwriter 10¢ only),
or automaticallly if enabled (refer to the auto answerback feature
in the Operator Guide).

Both

printable

the

answerback

and

control

characters
To

characters,

Answerback

Message

The

format

for

DCS

introducer

Protocol

the

message

Format
an answerback

ESC

selector

Data

terminator

DCS

Introducer

When

the

and

waits

the

ESC

terminal

for

ANSI

message

hexadecimal

encoded.

is:

P
Answerback

Message

Text

receives

the

introducer,

enters

correct

protocol

selector.

introducer

The

DCS

sequence

ESC

the

DCS

Encoded

DCS

and control characters can be part of
allow down line entry of both printable

message.

DCS

(octal

@33

DCS monde
introducer

129).

The protocol
selector
is
followed by the text of the answerback
message coded in hexadecimal
format.
The terminal
remains in DCS
mode
1f
the proper protocol selector is not received,
or if the
terminal
receives
a
character
that
is
out
of
range
before
the
correct

protocol

Protocol

selector

recognized.

Selector

After
receiving
the terminal to
selector

for

parameter

g6l)

and

the DCS
introducer,
the protocol
selector causes
enter answerback message entry mode. The protocol
answerback
message
entry
consists
of
a
numeric

final

(octal

character.

The

correct

protocol

166).

(octal

NOTE:\n\nWhen

the protocol selector is recognized the message
operating memory
is erased. However the message stored
in user permanent memory remains the same until the next store 1is
performed.
Stored

Data

After

the

proper

@37

and

--—

177

protocol

octal

selector

range)

are

received,

executed

control

usual.

characters

Hexadecimal digits (character in the 0606 -- @971, 191 -- 106, 141
-- 146 octal range) are grouped in pairs to give the hexadecimal
equivalent
of
the
character
to
be
entered
in
the
answerback
message. Any character from @ -- 177 (octal) can be entered in the
answerback message using the hex encoding system (see example).

When

the

protocol

operating

memory

selector
is

erased.

recognized

Then

the

message

character

1is

stored

added

in
the

message every time a pair of hexadecimal digits has been received.
NOTE:The message

padding
in

NUL

is not made

control

characters

long

characters are needed,

automatically.
If

they must be

included

the message.

Example:

The

following

DCS

introducer

|
l

string will

Protocol
I

| ==~

down

selector
Hex

| ===

| =r e

line

the message

encoded

message

LAl@0

DCS
I

terminator

| ——-|

ESC

)

ESC \

@33

120

¥61

166

064

103

064

061

063

@61

063

P60

063

P60

@33

not

Octal

134

Equivalent

Error Processing
Any character received
digit is discarded

odd

processed

the

number
by

hex

which

digits

1is

control

character

received,

the

1last

character

larger

hex

digit

1is

than

itself

value

received

HEX,
the character
(1A HEX).

for

replaced

Once
30
answerback message
characters are discarded.

the

SUB

control

characters

are

received,

character

further

Digital Equipment Corporation « Bedford, MA 01730