NBS TECHNICAL NOTE

478

Some Evolving Conventions and Standards

For Character Information Coded in

Six, Seven, and Eight Bits

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U.S. DEPARTMENT OF COMMERCE

National Bureau of Standards

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UNITED STATES DEPARTMENT OF COMMERCE

Maurice H. Stans, Secretary

NATIONAL BUREAU OF STANDARDS • A. V. Astin, Director

NBS TECHNICAL NOTE 478

ISSUED MAY 1969

Nat. Bur. Stand. (U.S.), Tech. Note 478, 27 pages (May 1969)

CODEN: NBTNA

Some Evolving Conventions and Standards

for Character Information Coded in

Six, Seven, and Eight Bits

John L. Little

Office of Information Processing Standards

Center for Computer Sciences and Technology

National Bureau of Standards

Washington, D.C. 20234

NBS Technical Notes are designed to supplement the Bureau's regular publications program. They provide a means for making available scientific data that are of transient or limited interest. Technical Notes may be

listed or referred to in the open literature.

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CONTENT!

Abstract

Page

IV

1. The Evolution of the USA Standard Code

for Information Interchange 1

2. Structure of Seven Bit ASCII 3

3. Six, Seven and Eight Bit Considerations 6

k. Structure of Eight Bit USASCII-8 6

5. Preferred 6Lj.-Character Subset 8

6. Representation of ASCII in Six Bits 8

7. Representation of Concepts Beyond the Code 9

8. Mapping Between Seven and Eight Bit Codes 11

9. Codes of More Than Eight Bits 13

10. Collating Sequence of ASCII and USASCII-8 13

11. Octal and Hexadecimal Representation of

the Coded Characters 16

12. Three Evolutionary Forms of ASCII 17

13. National Versions of Seven Bit Codes 18

lU. The Russian Code 19

ILLUSTRATIONS

Figures:

1. Standard Code Table, Seven Bit ASCII 23

2. Eight Bit Code Table, USASCII-8 2k

3. USASCII-8 Rearranged with Bit E6 Low 25

h. USASCII-8 Rearranged to aid Octal Users 26

5. Russian Code Table 27

III
Some Evolving Conventions and Standards for

Character Information Coded in Six, Seven, and Eight Bits

John L Little

ABSTRACT

This Technical Note describes some of the properties of the USA

Standard Code for Information Interchange, widely known as ASCII

or USASCIIo It also relates this code to similar international

codes and presents the national code for Russia as an example of the

worldwide acceptance of this code, which is comprised of seven

information bits representing 128 coded characters. Some of the

conventions which are evolving to relate these seven bit codes to

six and eight bit computer codes are given, and conventions for

extending the code to represent an unlimited repertoire of concepts

is also given Two alternate arrangements of the code table are

shown to facilitate an understanding of its structure and application..

Keywords: ASCII; character codes; code extension; coded character

sets; collating sequence; computer codes; data transmission codes;

information code structure; international information code; Russian

code standard; standard information codes; USASCII.

IV
1. The Evolution of the USA Standard

Code for Information Interchange

Coding of character-oriented information into binary bit patterns is

as old as automatic telegraphy, or about a century. Perforated tape

and punched cards have been in use since about the turn of the century.

Magnetic wire, tape, cores, drums and disks have come into widespread

use in conjunction with automatic recording of data and processing by

digital computers. Independent development of such equipment resulted

in a chabtic variety of conventions, and practices, for the physical

techniques as well as the logical coding patterns.

Punched card codes, usually attributed to Herman Hollerith, represented

originally numbers and signs, later letters and still later special

symbols. The evolution always retained historical features of earlier

structure, and these in turn influenced the coding of numbers, letters

and symbols in many electronic computers developed much later than

the card codes. Although the grouping of characters in card codes

influenced the grouping of characters in computer codes, the card codes

were never carried over and used internally in computers, since they

are not well suited for that purpose. Minor variations in the special

symbol codes used in punched cards is still creating much confusion,

but standardization is being attempted.

Perforated tape and magnetic tape grew and proliferated in much greater

variety of widths, recording densities and coding schemes. Standardization

is attempting to bring order out of the chaos.
Magnetic disk packs are currently proliferating, and the ckaos is

somewhat in evidence, but relatively early attempts are being made

to provide interchangeability of disk packs in order to increase

their utility to users. This requires standards for physical dimensions,

magnetic properties, track layout, recording techniques and density,

and coding of character information as well as automatic labels for

identification and data structure or format specification.

By i960 the chaos of data representation had reached such proportions

that a committee on computers and information processing, known as

X3> was established by the American Standards Association, Among its

goals was the establishment of a standard code for the representation

of character-oriented information, and standard implementations of tnat

code on the various media, such as magnetic tape, perforated tape,

punched cards, and electrical communication.

The complexity of the problem and the many conflicting requirements

facing the subcommittee X3.2, known as Codes and Input/Output, posed

an awesome task, requiring such diverse considerations as collating

sequence, keyboard conventions, provision of an adequate assortment

of graphic symbols, format effectors, communication controls, device

controls, and information separators, as well as appropriate subsets

for use in smaller coded character sets, and provisions for expansion

to encompass an unlimited repertoire of concepts not explicitly

embedded in the code proper,, These considerations and their resolution
as reflected in the code are given in greater detail in the appendices

to the standard (References 1 and 12).

The initials ASCII (pronounced ask'-ee) standing for "American Standard

Code for Information Interchange" as well as USASCII (pronounced yousass-key) standing for "USA Standard Code for Information Interchange"

have become familiar by now in many circles dealing with automated

information in coded form. The code is the United States' national

version of an international code adopted by several international

standardizing bodies and manufacturing associations. Many countries

have adopted their own national versions of this code and have given

it a mandatory legal status. The United States Government has adopted

it as a Federal Information Processing Standard (FTPS-l) and it will

become a common requirement in many government-supported and sponsored

systems: federal, state, and local.

2. Structure of Seven Bit ASCII

ASCII is a seven bit code having 128 coded character positions, as

shown in Figure 1. The seven bits are designated bl through b7 from

low order to high order of significance. The eight columns are numbered

through 7 corresponding to the octal values of the three high order

bits b5, b6, and b7. The sixteen rows are numbered through 1$ in

accordance with the four low order bits bl, b2, b3, and blj.. The code

extends from seven "zero" bits, the Null character (ML) to seven "one"

bits, the Delete character (DEL). Columns and 1 contain 32 control

characters and columns 2 through 7 contain 95 graphic characters and the Delete

character.
The meanings of the two-or three-letter groups in the ASCII code

table are given below. Definitions of these functions and names

of the single-symbol, graphic characters are given in the standard

(Reference 1)

NUL Null

SOH Start of Heading

STX Start of Text

ETX End of Text

EOT End of Transmission

ENQ Enquiry

ACK Acknowledge

BEL Bell (Audible or attention signal)

BS Backspace

HT Horizontal Tabulation (punched card skip) EM End of Medium

LF Line Feed SUB Substitute

VT Vertical Tabulation ESC Escape

FF Form Feed FS File Separator

CR Carriage Return GS

50 Shift Out RS

51 Shift In US

SP

DEL Delete

ASCII is frequently referred to as "an eight level code." This is

usually due to the addition of a parity bit in paper tape and a parity

DLE Data Link Escape

DC1 Device Control 1

DC2 Device Control 2

DC3 Device Control 3

DCU Device Control k (STOP)

NAK Negative Acknowledge

SYN Synchronous Idle

ETB End of Transmission Block

CAN Cancel

Group Separator

Record Separator

Unit Separator

Space
bit included in the character structure of communication systems.

The parity bit is not included in the code standard (Reference 1) but

its inclusion and sense (odd or even) are basic to certain other

standards which specify the implementation of the code in media or in

communication. There are also various implementations of the seven

bit code in eight bit environments, and the method of embedment of

the seven code bits within an eight bit environment has caused much

debate, but a resolution appears to have been achieved, as will be

discussed.

The 128 characters of ASCII are arranged in a collating sequence,

with ML low and DEL high in the sequence. The non-printing graphic

character Space (SP) collates ahead of all other graphic characters.

The collating sequence presents a natural arrangement for machine

sorting and file structuring, and it Is the principal consideration

in the structure of ASCII.

The ten decimal digits are positioned in order in column 3 so that

their value is represented by the binary values of the four low

order bits bl through bU. Upper case and lower case Latin alphabets

are each located in 26 contiguous positions. The code for an upper

case letter differs from its corresponding lower case letter in only

one bit, b6. Other collating and character positioning considerations

are given in section 10 and in the standard (Reference 1),
3. Six, Seven, and Eight Bit Considerations

Original efforts to develop a standard code for general information

interchange, in the early 1960's, attempted to limit the code to six

bits, in which there can be only 6U uniquely coded characters. This

was soon deemed to be inadequate, although most computers of that

era represented characters in only six bits. Seven bits was deemed

to be the optimum size, with its attendant 128 unique coded bit

patterns, and that size was selected for ASCII. Eight bits was deemed

to be wasteful because of the need to transmit the extra bit in communication

systems.

Because computer design favors eight-bit groups in preference to

seven bits for several cogent technical reasons, an eight-bit form

of ASCII may become even more prevalent than the seven-bit form

currently used in several communication systems.

h. Structure of Eight Bit USASCII-8

Placement of the 128 ASCII characters within the framework of eightbits, with its 2^6 positions, has been a subject of intense controversy

in standardizing circles for several years, but it appears to have

stabilized into Hie form shown in Figure 2, in which the ASCII characters

are in the left-half of the eight-bit code table, where the high

order bit (E8) is zero.

In ASCII the seven bits are designated bl through b7, while in

USASCII-8 the bits are designated El through E8. In these notations,
"b" stands for "bit" and "E" is used for distinction, apparently

having come from the first letter of the word "eight."

Several arbitrary conventions have been evolved for the eight-bit

code table of Figure 2. The table has 16 rows designated through

15, and 16 columns designated with dual decimal digits 00 through

15. Positions in the table are specified by the column and row number

separated by a slant (slash) symbol. Thus the capital letter "T"

occupies position 05/U and the control "Carriage Return" (CR) occupies

00/13. The double digits 00 through 15 for column number distinguish

this notation from the similar seven-bit ASCII notation which has

only one digit for column number (0 through 7).

Specific standard character assignments for the right half of Figure

2, in which the high order bit E8=l, have not yet been made, except

possibly for EO, the eight ones position, which is immutable. However,

it is well agreed that columns 08 and 09 should contain additional

control characters, designated for reference as KO through K31 and

that the other six columns 10 through 1$ should contain 95 additional

graphic characters and EO. The graphics designated as NO through N63

map into the center four columns of ASCII. The graphics designated

GO through G30 differ from the lower case alphabet positions only

in bit E8, and hence are said to map from columns lU and 1$ into columns

6 and 7 if bit E8 is ignored or dropped.
5>. Preferred 6U-Character Subset

The center four columns (2,3>h,$) of ASCII have become recognized as a

preferred 6l4-character subset, which can be represented in six bits

by dropping bit b6, (or by dropping bits E6 and E8 in USASCII-8).

This 6L|.-character subset can be (and often is) represented in seven

bits and eight bits.

6. Representation of ASCII in Six Bits

A six-bit code is constrained to 6I4 unique characters. Sometimes

it is desired to represent the ASCII set of 128 characters or even

more in six-bit systems. In the six-bit world of seven-track magnetic

tape, especially in Europe, the six bits normally represent the 6I4.

characters shown in columns 2,3.? U> and 5 of Figure 1 with bit b6

being ignored. (In library work, though, the 6 -bits usually represent

characters in columns 2,3*6, and 7.) In this situation, the character

"Underline" in position 5/15> serves as a flag character whose meaning

isr the next six-bit character following the flag is from one of the

outside four columns of ASCII, two positions to the left or right of

the normal position from the 6I4 character set. This scheme allows

for the representation of 6k additional concepts as two-character

sequences. A "real Underline" is represented as two successive

Underlines, and hence the character "Delete" in 7/15> cannot be represented

by this particular convention.
7. Representation of Concepts Beyond the Code

The 7-bit ASCII is constrained to the 128 characters shown in Figure

1 or in the left half of Figure 2. Pressure has naturally arisen

from many user sources to allow for the representation of concepts

not explicitly representable in ASCII. This pressure has been noted

in 6, 7, and 8 bit environments. Several preferred solutions are

becoming apparent.

If a system is constrained to exist in seven bits, then additional

concepts can be provided with the aid of four of the ASCII control

characters: "Shift Out" (SO) in 0/1 U, "Shift In" (Si) in 0/15, "Escape"

(ESC) in 1/11, and "Data Link Escape" (DIE) in 1/0.

SO is used as a precedence character to alter the interpretation

of succeeding graphic characters from columns 2 through 7 until the

corresponding SI character appears and restores the normal ASCII

interpretation to those graphic characters. In seven-bits, the

meanings of the control characters in columns and 1 remains unchanged

by SO or SI.

The character "Data Link Escape" (DLE) in 1/0 is used exclusively

to alter the interpretation of immediately succeeding ASCII communication

control characters from columns and 1 of Figure 1. There are ten

of these (SOH, STX, ETX, EOT, ENQ, ACK, DLE itself, NAK, SYC\T, and ETB).

All ten of these are from the top half of columns or 1.

The character "Escape" (ESC) in 1/11 provides the greatest flexibility

and unlimited capability of any. A convention appears to be evolving

prescribing the use of ESC in seven bits, as follows: If the character
ESC is immediately followed by any graphic character from columns 3 }

h, 5, 6, or 7, then that two-character sequence defines a new

concept, which may be graphic or control in nature. If the character

ESC is immediately followed by an appropriate control character

from columns or 1 (such as a "format effector," a "device control"

or an "information separator" character) then that two-character

sequence defines a new control concept which is closely related

to the normal control function of the character following ESC. The

expressions "locking" or "non-locking" are commonly used in an

obvious manner to describe the duration of the newly defined concept.

The "locking" actions can endure until an "unlocking" action occurs.

"Locking" features can be cascaded one over the other, and a master

"restore" convention has not been prescribed as a standard.

Unlimited possibilities occur if the character ESC is immediately

followed by a graphic character from column 2 of Figure 1, still

confining our attention to seven bits. Complete details are yet

lacking, but in Europe a convention is evolving around the definition

of three-character Escape sequences in which the first character is

ESC, the second character is a graphic from column 2, and the third

is a "final" character, which can be any graphic character from

columns 3, h, 5, 6, or 7, or any suitably selected character from

columns or 1. The class of a concept defined by a three-character

sequence is determined by the middle character, from column 2, and

the classification is as follows, where "(F)" represents a "final"

character:

10
Sequence to Represent

ESC I (F) Device controls

ESC " (F) Format controls

ESC # (F) Sets of controls "K" in 8 bits,

columns 08 and 09

ESC $ (F) Control sets in 7 bits

ESC % (F) Shift Out sets in 7 bits

ESC & (F) Sets (columns to 7) in 7 bits

ESC ' (F) Sets with more or less than 7 bits

ESC -«- (F) National choice sets in 7 bits

Four-character Escape sequences can be generated using ESC followed

by two characters from column 2 and a final character. All fourcharacter Escape sequences are reserved for private use, not subject

to standardization.

Having defined means for representing an unlimited repertoire of

concepts in seven bits, we now come to the matter of representing

these concepts in eight bits and of relating the seven and eight bit

representations

8. Mapping Between Seven and Eight Bit Codes

Figure 2 is an eight-bit code table with the left half fully defined

as representing the 128 characters of ASCII. The right half is

defined only as having 32 controls, 95 graphics and the Eight Ones (EO)

character. It is unlikely that the right half will ever be defined

as fully as the left half for general use. Instead, it is likely that

a family of eight bit codes will evolve, each for a particular community

11
of interest, representing such communities as libraries, typesetting,

mathematics, organic chemistry, non-Latin alphabets, and many

others.

Referring again to Figure 2, we can think of the whole table as

representing an eight-bit code. Or if we choose, we can ignore

bit E8 and think of the table as representing two seven bit code

tables, the left one being ASCII, and the right one containing

the Shift Out set of graphics.

We note that there are 9$ graphic characters in ASCII, including

Space (SP) in 02/0, and we note that there are 9$ graphic characters

of either the N-type or G-type on the right half. Each of these

190 graphic characters has a unique bit code in eight bits, and hence,

in eight bits, they can be interspersed in a. character stream in any

order, without the use of the shift characters Shift Out (SO) or

Shift In (Si). The information conveyed by SO and SI (in seven

bits) is now inherent in the eighth bit E8.

In making a translation from a seven bit character stream into an

eight bit stream, we can monitor for SO and SI, use these to set bit

E8 for subsequent eight bit characters, and then either discard

or retain the SO and SI characters.

In going from a stream of eight bit graphic characters into a seven

bit stream, we can monitor bit E8, and when it changes, we can insert

an SO or SI character into the seven bit stream, to retain the

information conveyed by bit E8.

12
A convention has been gaining favor relating the 32 "K" controls

of columns 08 and 09 into two -character sequences in seven bits,

having ESC as the first character and a corresponding graphic from

columns h or $ as the second character. In this transform, the

six low-order bits of the graphic character (bl through b6) match

the six low-order bits of the K control (El through E6). In the

reverse process, going from seven bits to eight bits, a two-character

sequence comprised of ESC followed by a, graphic character from columns

k or £, transforms into a single eight bit control character in

columns 08 or 09, in a position corresponding to the position

of the graphic character. Other multi-character Escape sequences

remain the same in seven and eight bit streams.

9. Codes of More than Eight Bits

At the present time there does not appear to be any particular interest

in conventions for representing characters in codes larger than eight

bits, although devices exist, such as typesetting mechanisms, in which

more than eight bits are used to represent each character, and

coding schemes are used in computers in which two eight -bit groups

are used to represent a character or an image of a character (Reference 6)

10 o Collating Sequence of ASCII and USASCII-8

The 1963 version of the ASCII standard (Reference 3) disassociates

ASCII from collating sequence with the sentences in section 5 1„

13
"The standard code does not include any redundancy or define techniques

for error control. Further , it does not specify a standard collating

sequence." However , that position is reversed in 196$ ASCII (Reference 2) and in the current ASCII (Reference l) in section 6.3 which reads

"The relative sequence of any two characters, when used as a. basis

for collation, is defined by their binary values."

Figure 2 defines a collating sequence for the 25>6 characters of the

eight bit code, with the character NUL as the lowest in the sequence,

SOH next, and so on, with EO (Eight Ones) being the highest The

graphic character Space (Sp) collates lower than any other graphic

character.

Complaints are sometimes heard that all of the upper case letters

collate below all of the lower case letters, and that miscellaneous

symbols collate between the upper and lower case alphabets. It is

obvious from Figure 2 that these complaints are valid. However,

the painstaking structure of ASCII, in which collating sequence is

probably the dominant (though far from the only) feature allows

for a variation such as that shown in Figure 3.

Figure 3 is a rearrangement of Figure 2 in which bit E6 has been

moved to the lowest order position, and bits El through E£ are

moved up one place.

In Figure 3, the alphabetic characters collate in the sequence A, a,

B, b, C, c, etc., with no gaps in the sequence from A to z.

Ill
The character Space (SP) collates lower than all other characters,

graphic as wall as control, except for the character Null (NUL).

The numerals through 9 still collate in the proper sequence, but

they are interspersed with control characters and other graphic

characters intervene between the numerals and the letters, as in the

ASCII collating sequence.

At first glance this appears to be a highly advantageous arrangement

for purely alphabetic material, and such interspersed alphabets have

accordingly been used in some computer codes. However, there are

some highly subtle flaws in this collating sequence, as is vividly

illustrated in Reference 10.

For example, if a sort were made on alphabetic material using the

interleaved letter collating sequence of Figure 3, then all words

beginning with lower case letter 'a" would follow all words beginning with capital "A", which is not the arrangement usually desired

in listings of mixed upper and lower case material, suci as those

found in dictionaries, telephone directories, or library catalogs.

iThe case distinction must be ignored, by ignoring bit b6 or E6,

for sorting, but the case distinction must be retained for printing

and for fine sorts. More detailed consideration is given in

Reference 11.

Note that there is no bit reassignment i^hatever between Figure 2

and Figure 3. Only the order of presentation is different,, But

15
the interspersed alphabets of Figure 3 may suggest some of the

flexibility inherent in ASCII „ By suitable logical bit manipulation, one could obtain the interspersed alphabets of Figure 3

and the contiguous digits of Figure 2.

11. Octal and Hexadecimal Representation of the Coded Characters

The column/row notation of Figures 2 and 3 is readily convertible

to hexadecimal (libit) notation. Single decimal digits through

9 are used for both column and row, while 10 through 1$ are usually

represented as single capital letters A through F for both column

and row.

The arrangements of the code tables of Figures 1 or 2 make translation

of the bit patterns into octal (3 bit) characters quite an awkward

operation, since the bits are not grouped conveniently for that

purpose, and the octal characters do not come out even for either

seven or eight bits, although they would for six or nine bits, with

no leftover bits.

When seven bit characters are represented in octal form, three

octal digits are required to represent each character, and the

high order octal digit is always either zero or one, as shown

in the top half of Figure h° In representing all 2^6 eight-bit

characters, the high order octal digit can be 0, 1, 2, or 3o The

other two octal digits can, of course, have any value from to 7.

The octal digits are shown explicitly in Figure h instead of column

16
and row numbers „ The code table arrangement, of Figure k, was suggested by Crosby (Reference 7)

12. Three Evolutionary Forms of ASCII

The seven bit ASCII (American Standard Code for Information Interchange)

has existed in its evolution in three distinct, but closely related

versions o The first was known as American Standard X3oli - 1963, approved

by the American Standards Association on June 17, 1963 (Reference 3).

It did not contain lower case letters, nor the characters Backspace,

Underline, and several others which have been added subsequently

The second version was an extensive revision approved by ASA as

X3oii - 1965 but never distributed to the public due to pending

international modifications in the ISO 7-bit code,, However, the 1965>

version was published as a proposed revision. (Reference 2) along

with an exposition on the evolution of the ISO 7-bit code.

The present version is known as the United States of America Standard

Code for Information Interchange, X3.U - 1967 ^ approved by the United

States of America Standards Institute (successor to ASA) on July 7,

1967. This version was adopted as a Federal Standard by President

Lyndon B. Johnson in a memorandum for the Heads of Departments and

Agencies, dated March 11, 1968. The latest version was published

in 1968 as a combined ASCII and Federal Information Processing

Standard, FIPS - 1 (Reference 12).

17
The evolution of ASCIIs now also called USASCII, was influenced

heavily by concurrent developments of international 7-bit codes,

particularly the ISO 7-bit code (Reference h) and the CCITT Alphabet

No. 5, which is destined to become the successor to CCITT Alphabet

No. 2, the international five -bit Baudot code, which is still in

extensive but diminishing use.

The 1965 version of ASCII represented a major renaming and repositioning

of the control functions from those originally appearing in the 1963

standard. The graphic characters "Up arrow" and "Left arrow" and the

control character "RU" (Are you.„.?) were removed and replaced by

other characters. The character "@" (Commercial At) was moved

from U/0 to 6/0, but because of many complaints, it was moved back

to U/0 in the 1967 ASCII. "Commercial At" was originally moved to

make room for the character "Underline" in the preferred center four

columns. In a. CCITT meeting the Russian delegate requested that

Underline be moved from I4/O to 5/15 so as to pair with Delete, and

make room for 31 Cyrillic alphabetic characters in both upper and

lower case, displacing all of the characters from columns U, 5, 6, and

7 except Underline and Delete, as shown in the right half of Figure 5.

13. National Versions of the Seven Bit Codes

The Seven Bit Code of the International Organization for Standardization

(Reference h) and the nearly identical international communications

code of the International Consultative Committee on Telegraph and

Telephone (CCITT) contain eleven code table positions which are

18
reserved in varying degrees for "National Use." These eleven

positions are 2/3, U/0, 5/11, 5/12, 5/13, 5/lU, 6/0, 7/11, 7/12,

7/13, and 7/lU. Position 2/3 is known to contain only the number

sign (#) and the symbol for "Pound Sterling." All of the other

positions contain a variety of symbols. ASCII has assigned the

United States' preferred symbols to these positions, and it is

noted that many other nations have assigned the same symbols where

there was no other need. Some of the ASCII national use symbols are

shown as preferred assignments in the ISO code.

lU . The Russian Code

In a USSR State Standard (Reference 8) the Russians have changed

"Shift Out" to "Russian Register" and "Shift In" to "Latin Register.

In the Russian register, they have placed uppercase Cyrillic characters

in columns corresponding to lowercase Latin letters as shown in Figure

5, a seven bit code. Only 31 of the usual 33 Cyrillic letters are

included. Omitted is the silent symbol which resembles "bl" aid the

"E" or "e" with the double-dot (diaeresis) diacritical overmark. The

Cyrillic letters are arranged to match their Latin phonetic equivalents,

rather than being placed in alphabetical order. This facilitates LatinCyrillic keyboard pairing, but complicates alphabetical sorting by computer

of Cyrillic data.

The placement of uppercase Cyrillic letters in columns corresponding

to lowercase Latin letters was done to facilitate a third seven-bit code

arrangement, not illustrated, which has all lowercase letters removed,

19
and both Latin and Cyrillic uppercase letters in their usual positions.

This permits monocase operations with both Latin and Cyrillic alphabets

without the use of Shift Out and Shift In characters.

Use of the Russian code is explained in more detail in Reference 9-

20
References

1. (1967 ASCII) "USA Standard Code for Information Interchange,"

X3.U-1967. Available for $2.00 from United States of America

Standards Institute, 10 East l|0th Street, New York, N. I. 10016.

Also approved as Federal Information Processing Std. (FIPS-l).

2. (1965 ASCII) "Proposed Revised American Standard Code for

Information Interchange," Communications of the ACM, Vol. 8,

No. k, April 1965, pp. 207-211IT

3. (1963 ASCII) "American Standard Code for Information Interchange,"

approved June 17, 1963 by the American Standards Association

(now USASI, Ref. 1 above), no longer in print, but code table

shown in Ref. 2.

U. (ISO 7 Bit Code) "6 and 7 Bit Coded Character Sets for Information

Processing Interchange, " ISO Recommendation R6i|6, International

Organization for Standardization, available for $6.00 from USA

Standards Institute (see Ref. 1 above).

5. (USASCII-8) "Interchange Code Adds an Eighth Bit," by Eric

H. Clamons, C ontrol Engineering , July 1968, pp. 76-78.

6. (GPSDIC) "The Document Image Code System," National Bureau

of Standards Technical News Bulletin, Vol. 52, No. h, April

1968, pp. 86-88.

7. "Note on an ASCII-Octal Code Table" by Wm. S. Crosby, C ommunic at ions of the ACM , Vol. 8, No. 10, October 1965, p. 6l6.

8. USSR State Standard GOST 13052-67, "Computers and Data

Transmission Equipment Alpha-Numeric Codes," approved by

the Committee of Standards, Measures, and Measuring Equipment

of the Council of Ministers, USSR, July 10, 1967. Translator:

Mrs. A. Werner, and Editor of Translation: D. A. Kerr, Bell

Telephone Laboratories, Inc., Holmdel, New Jersey, June 25, 1968.

9. "Standard Data Transmission Code" by P. A. YeskLn and 0. P.

Kireyeo, Tele commani cations (USSR ) , published in English as Tele - communications and Radio Engineering, Vol. 22, No. 2, February,

1968, pp. 2h-2B, Scripta Publishing Corp., Washington, D. C.

10. "ESC Facility in USASCII," a letter by R W„ Bemer, in

Communications of the ACM, Vol. 10, No. U, April 1967, p. 202.
11. "Computer Filing of Index, Bibliographic, and Catalog Entries,"

by T. C. Hines and J. L. Harris, Bro-Dart Foundation, Newark,

No J., 1966, L. C. Cat, Card No. 66-23U8i|.

12. (1968 ASCII) "USA Standard Code for Information Interchange,"

published jointly as X30I4 - 1968 and FIPS-1. A very minor

revision of Ref . 1. The revisions, allowing "New Line" as an option for "Line Feed" is not included in FIPS-1.

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