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BCD (character encoding)

April 10, 2024

Not to be confused with four-bit numeric binary-coded decimal.

BCD (binary-coded decimal), also called alphanumeric BCD, alphameric BCD, BCD Interchange Code,[1] or BCDIC,[1] is a family of representations of numerals, uppercase Latin letters, and some special and control characters as six-bit character codes.

BCD Interchange Codes
Classification6-bit alphanumeric basic Latin encodings
Succeeded byEBCDIC

Unlike later encodings such as ASCII, BCD codes were not standardized. Different computer manufacturers, and even different product lines from the same manufacturer, often had their own variants, and sometimes included unique characters. Other six-bit encodings with completely different mappings, such as some FIELDATA[1] variants or Transcode, are sometimes incorrectly termed BCD.

Many variants of BCD encode the characters '0' through '9' as the corresponding binary values.

History edit

Technically, binary-coded decimal describes the encoding of decimal numbers where each decimal digit is represented by a fixed number of bits, usually four.

With the introduction of the IBM card in 1928, IBM created a code[a] capable of representing alphanumeric information,[2] later adopted by other manufacturers. This code represents the numbers 0-9 by a single punch, and uses multiple punches for upper-case letters and special characters.[3] A letter has two punches (zone [12,11,0] + digit [1–9]); most special characters have two or three punches (zone [12,11,0,or none] + digit [2–7] + 8).

The BCD code is the adaptation of the punched card code to a six-bit binary code by encoding the digit rows (nine rows, plus unpunched) into the low four bits, and the zone rows (three rows, plus unpunched) into the high two bits.[4] The digit zero (a single punch in row 0) is usually handled specially in some way, and the digit code was extended to values 10 through 15 by combining a digit in the range 2–7 with a punch in row 8. IBM applied the terms binary-coded decimal and BCD to the variations of BCD alphamerics used in most early IBM computers, including the IBM 1620, IBM 1400 series, and non-Decimal Architecture members of the IBM 700/7000 series.

Among the vendors using BCD were Burroughs,[5] Bull, CDC,[6] IBM, General Electric (the computer division was purchased by Honeywell in 1969), NCR, Siemens, and Sperry-UNIVAC.

IBM announced the 8-bit Extended Binary Coded Decimal Interchange Code (EBCDIC), based on BCDIC, in 1964 with the introduction of its System/360 line.

Special characters edit

The Recordmark or Record mark character (represented as ‡) is a character used to mark the end of a record.[7] The BCD code for this character is 328 in some BCD variants. The closest Unicode equivalent is U+29E7 ⧧ THERMODYNAMIC, but that is not found in many fonts, so U+2021 ‡ DOUBLE DAGGER is often used instead. Functionally this corresponds to the EBCDIC IRS character (ASCII RS), X'1E'.

The Groupmark or Group mark character (represented as  ) is a character used to indicate the start or finish of a group of related fields.[8] The BCD code for this character is 778 in some BCD variants. The groupmark was proposed for Unicode standardization in 2015,[9] and was assigned to value U+2BD2 ⯒ GROUP MARK. Functionally this corresponds to the EBCDIC IGS character (ASCII GS), X'1D'. It is now in Unicode 10.0 at this position, but only the Symbola and Unifont fonts support it.

The Wordmark, by contrast, is not a BCD character. Rather, it is a flag bit used to mark the end of a word on some variable word length computers such as the IBM 1401.

BCD code variations edit

There are many different versions of the six-bit BCD code. There are three major categories of difference:

  1. The mapping from zone punches to high-order bits. All codes translate no zone punches to a bit pattern of 00, but some encode the zone punches in 12-11-0 order, preserving alphabetical order, while others use 0-11-12 order, resulting in a partially reversed alphabet.
  2. The handling of the digit 0. The straightforward translation from punched form would place the blank before digits 1–9, and encode 0 at the start of the line with 'S' in it. All codes have some special-case handling which either translates the digit 0 to the all-zero binary code (and moves the blank elsewhere), or gives it binary code 001010 (decimal 10) and moves the 8+2 punch elsewhere.
  3. The assignment of special characters. The characters assigned to codes beyond the basic alphanumeric set varied widely, even within one model of computer.

In "Spanish speaking countries", the character "Ñ" did not exist in the original system, therefore "@" was chosen by most manufacturers: Bull, NCR, and Control Data, but there was an inconsistency when merging databases to 7-bit ASCII code, for in that coding system the "/" character was chosen, resulting in two different codes for the same character.

Examples of BCD codes edit

The following charts show the numeric values of BCD characters in hexadecimal (base-16) notation, as that most clearly reflects the structure of 4-bit binary coded decimal, plus two extra bits. For example, the code for 'A', in row 3x and column x1, is hexadecimal 31, or binary '11 0001'.

Tape style edit

48-character BCD code edit

The first versions of BCDIC had 48 characters, as they were based on card punch patterns and the character sets of printers, neither of which encouraged having a power-of-two number of characters.

IBM 48-character BCDIC code[1]: 68 
x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF
0x space 1 2 3 4 5 6 7 8 9 0 # @
1x / S T U V W X Y Z , %
2x - J K L M N O P Q R $ *
3x & A B C D E F G H I . ⌑

This was based on a 40-character punched card code; the original 37 (10 digits, 26 letters, and blank), plus three commercially important characters added around 1932:[1]: 67  hyphen-minus used for printing credit balances and hyphenated names, the ampersand also used in many names and addresses (Procter & Gamble, Mr. & Mrs. Smith), and the asterisk used to overprint unused fields when printing cheques.

IBM 1401 BCD code edit

Rather than following the IBM 704's storage representation, IBM 1401 followed the tape representation (descended from the 48-character BCD), thus using the all-zero code for blank and the code 10 (0x0A) for the digit zero. It had defined character forms for all possible values, for documentation purposes,[10] but only 48 of the 63 non-blank characters were printable, and there was considerable variation in how the other code values (shaded in the table below) were depicted in practice. Even the other characters varied between different available print chains for the IBM 1403 printer.

x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF
0x space 1 2 3 4 5 6 7 8 9 0 # @ : > √
1x ¢ / S T U V W X Y Z ⧧ , % = ' "
2x - J K L M N O P Q R ! $ * ) ; Δ
3x & A B C D E F G H I ? . ⌑ ( < ⯒

Code page 353 edit

The BCDIC-A Code page was assigned as Code page 353, also known as CP353. Some of the characters in this code page are not in Unicode. (The duplication of '#' can be found in IBM's own documentation and is not a mistake here.[11])

x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF
0x space 1 2 3 4 5 6 7 8 9 0 # @ : > √
1x ␢ / S T U V W X Y Z ⧧ , % γ \ ⧻
2x - J K L M N O P Q R ! # * ] ; Δ
3x & A B C D E F G H I ? . ⌑ [ < ⯒

At 0x1A is the record mark. At 0x3F is the group mark.

PTTC/BCD code pages edit

PTTC/BCD had 5 options. There were five code pages. They are shown below. The PTTC/BCD Standard Option was assigned as Code page 355, or CP355.

x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF
0x space 1 2 3 4 5 6 7 8 9 0 #
1x @ / S T U V W X Y Z ⧧ , γ
2x - J K L M N O P Q R < $
3x & A B C D E F G H I ) .

The PTTC/BCD H Option was assigned as Code page 357, or CP357.

x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF
0x space 1 2 3 4 5 6 7 8 9 0 =
1x ' / S T U V W X Y Z ⧧ ,
2x - J K L M N O P Q R ! $
3x + A B C D E F G H I ? .

The PTTC/BCD Correspondence Option was assigned as Code page 358, or CP358.

x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF
0x space 1 2 3 4 5 6 7 8 9 0 '
1x ! / S T U V W X Y Z ⧧ ,
2x - J K L M N O P Q R < ;
3x = A B C D E F G H I > .

The PTTC/BCD Monocase Option was assigned as Code page 359, or CP359.

x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF
0x space 1 2 3 4 5 6 7 8 9 0 #
1x @ / S T U V W X Y Z ,
2x - J K L M N O P Q R $
3x & A B C D E F G H I .

The PTTC/BCD Duocase Option was assigned as Code page 360, or CP360.

x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF
0x space 1 2 3 4 5 6 7 8 9 0 #
1x @ / S T U V W X Y Z ,
2x - J K L M N O P Q R $
3x & A B C D E F G H I .

IBM 704 storage style edit

IBM 704 BCD code edit

The IBM 704 reordered the BCDIC code to allow a normal alphabetic collating order internally, with 0 before 1 and A before Z. It could automatically translate between this internal form and the earlier BCDIC when reading and writing magnetic tapes.[12]: 35 

The following table shows the code assignments for the IBM 704 computer. Unassigned code positions appear as blanks.[12]: 35 

IBM 704 character set
x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF
0x 0 1 2 3 4 5 6 7 8 9 # @
1x & A B C D E F G H I +0 . ⌑
2x - J K L M N O P Q R −0 $ *
3x space / S T U V W X Y Z ⧧ , %

(+0 and −0 were rarely used characters that corresponded to the punched-card convention of a digit 0 with an overpunched sign in rows 12 or 11.)

The following table shows the code assignments for the type 716 printer used starting with the IBM 704 computer and through the 7094.[12]: 58  The 704 interface[b] sent virtual punched-card rows to this printer, two words (72 bits) at a time, so the mapping from 6-bit BCD characters was done by software, and was not built into the printer.

IBM 716 printer character set G
x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF
0x * 1 2 3 4 5 6 7 8 9 + -
1x + A B C D E F G H I . ⌑
2x - J K L M N O P Q R $ *
3x 0 / S T U V W X Y Z , %

This is a repertoire of 45 characters (not counting blank, which is handled specially by the printer), as the characters +, - and * are duplicated.

Fortran character set edit

There was some variation; IBM 704 Fortran had a different set of special characters (preserving only the duplicated minus sign).[13]

IBM 716 printer Fortran character set
x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF
0x * 1 2 3 4 5 6 7 8 9 = -
1x + A B C D E F G H I . )
2x - J K L M N O P Q R $ *
3x 0 / S T U V W X Y Z , (

A similar code was used for the IBM 709, 7090 and 7094 successors,[14] but with some of the special characters reassigned:

IBM 7090/7094 character set
x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF
0x 0 1 2 3 4 5 6 7 8 9 = "
1x & A B C D E F G H I +0 . )
2x - J K L M N O P Q R −0 $ *
3x space / S T U V W X Y Z ± , (

GBCD code edit

Below is the table of GE/Honeywell's GBCD code, a variant of BCD.[15]

x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF
0x 0 1 2 3 4 5 6 7 8 9 [ # @ : > ?
1x space A B C D E F G H I & . ] ( < \
2x ^ J K L M N O P Q R - $ * ) ; '
3x + / S T U V W X Y Z _ , % = " !

Burroughs B5500 BCD code edit

The following table shows the code assignments for the Burroughs B5500 computer, sometimes referred to as BIC (Burroughs Interchange Code).[16]

x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF
0x 0 1 2 3 4 5 6 7 8 9 # @ ? : > ≥
1x + A B C D E F G H I . [ & ( < ←
2x × J K L M N O P Q R $ * - ) ; ≤
3x space / S T U V W X Y Z , % ≠ = ] "

See also edit

Notes edit

  1. ^ There are actually multiple card codes, e.g, by 1964 there were ten versions of the IBM 026 with slightly different character sets.
  2. ^ The interface on, e.g., the 7090, is different, although the software still must do mapping.

References edit

  1. ^ a b c d e Mackenzie, Charles E. (1980). Coded Character Sets, History and Development (PDF). The Systems Programming Series (1 ed.). Addison-Wesley Publishing Company, Inc. ISBN 0-201-14460-3. LCCN 77-90165. (PDF) from the original on 2016-05-26. Retrieved 2017-04-22. [1]
  2. ^ Pugh, Emerson W.; Heide, Lars. . IEEE Global History Network. Archived from the original on 2012-05-11. Retrieved 2012-06-09.
  3. ^ Pugh, Emerson W. (1995). Building IBM: Shaping and Industry and Its Technology. MIT Press. pp. 50–51. ISBN 978-0-262-16147-3.
  4. ^ Jones, Douglas W. "Punched Card Codes". Retrieved 2014-01-01.
  5. ^ (PDF). Burroughs Corporation. 1964. Archived from the original (PDF) on 2020-07-29. Retrieved 2012-06-08.
  6. ^ Control Data Corporation (1965). Codes/Control Data 6600 Computer System (PDF).
  7. ^ "Record-mark". Encyclopedia. PC Magazine. Retrieved 2016-04-09.
  8. ^ "group mark". Encyclopedia.com. Retrieved 2016-04-09.
  9. ^ Shirriff, Ken. "Proposal for addition of Group Mark symbol" (PDF). unicode.org. Retrieved 2016-04-09.
  10. ^ (PDF). IBM. April 1962. p. 170. A24-1403-5. Archived from the original (PDF) on 2012-03-14.
  11. ^ (PDF). www-03.ibm.com. Archived from the original (PDF) on 2013-01-21. Retrieved 2022-06-30.
  12. ^ a b c IBM 704 electronic data-processing machine manual of operation (PDF). IBM. 1955. pp. 35, 58. Form 24-6661-2. Retrieved 2017-04-22.
  13. ^ "Fortran Automatic Coding System for the IBM 704" (PDF). IBM. 1956-10-15. p. 49. Retrieved 2015-09-15.
  14. ^ Harper, Jack (2001-08-21). "IBM 7090/94 Character Representation". Retrieved 2017-04-22.
  15. ^ (PDF). Archived from the original (PDF) on 2011-07-08. Retrieved 2010-11-15.
  16. ^ Burroughs B 5500 Information Processing Systems Extended Algol Reference Manual (PDF). 1966. p. B-1.

Further reading edit

  • (PDF). Bull S.A. CEDOC. November 2003. 67 A2 RJ78 REV00. Archived from the original (PDF) on 2015-02-12.
  • Bonten, Jo H. M. (2009-03-08) [2007]. "Data formats in old 48- and 36-bits computers: Six-bits characters". Geldrop, Netherlands. from the original on 2016-06-16. Retrieved 2016-06-16.

April 10, 2024
character, encoding, confused, with, four, numeric, binary, coded, decimal, binary, coded, decimal, also, called, alphanumeric, alphameric, interchange, code, bcdic, family, representations, numerals, uppercase, latin, letters, some, special, control, characte. Not to be confused with four bit numeric binary coded decimal BCD binary coded decimal also called alphanumeric BCD alphameric BCD BCD Interchange Code 1 or BCDIC 1 is a family of representations of numerals uppercase Latin letters and some special and control characters as six bit character codes BCD Interchange CodesClassification6 bit alphanumeric basic Latin encodingsSucceeded byEBCDICvteUnlike later encodings such as ASCII BCD codes were not standardized Different computer manufacturers and even different product lines from the same manufacturer often had their own variants and sometimes included unique characters Other six bit encodings with completely different mappings such as some FIELDATA 1 variants or Transcode are sometimes incorrectly termed BCD Many variants of BCD encode the characters 0 through 9 as the corresponding binary values Contents 1 History 2 Special characters 3 BCD code variations 4 Examples of BCD codes 4 1 Tape style 4 1 1 48 character BCD code 4 1 2 IBM 1401 BCD code 4 1 3 Code page 353 4 1 4 PTTC BCD code pages 4 2 IBM 704 storage style 4 2 1 IBM 704 BCD code 4 2 2 Fortran character set 4 2 3 GBCD code 4 2 4 Burroughs B5500 BCD code 5 See also 6 Notes 7 References 8 Further readingHistory editTechnically binary coded decimal describes the encoding of decimal numbers where each decimal digit is represented by a fixed number of bits usually four With the introduction of the IBM card in 1928 IBM created a code a capable of representing alphanumeric information 2 later adopted by other manufacturers This code represents the numbers 0 9 by a single punch and uses multiple punches for upper case letters and special characters 3 A letter has two punches zone 12 11 0 digit 1 9 most special characters have two or three punches zone 12 11 0 or none digit 2 7 8 The BCD code is the adaptation of the punched card code to a six bit binary code by encoding the digit rows nine rows plus unpunched into the low four bits and the zone rows three rows plus unpunched into the high two bits 4 The digit zero a single punch in row 0 is usually handled specially in some way and the digit code was extended to values 10 through 15 by combining a digit in the range 2 7 with a punch in row 8 IBM applied the terms binary coded decimal and BCD to the variations of BCD alphamerics used in most early IBM computers including the IBM 1620 IBM 1400 series and non Decimal Architecture members of the IBM 700 7000 series Among the vendors using BCD were Burroughs 5 Bull CDC 6 IBM General Electric the computer division was purchased by Honeywell in 1969 NCR Siemens and Sperry UNIVAC IBM announced the 8 bit Extended Binary Coded Decimal Interchange Code EBCDIC based on BCDIC in 1964 with the introduction of its System 360 line Special characters editThe Recordmark or Record mark character represented as is a character used to mark the end of a record 7 The BCD code for this character is 328 in some BCD variants The closest Unicode equivalent is U 29E7 THERMODYNAMIC but that is not found in many fonts so U 2021 DOUBLE DAGGER is often used instead Functionally this corresponds to the EBCDIC IRS character ASCII RS X 1E The Groupmark or Group mark character represented as nbsp is a character used to indicate the start or finish of a group of related fields 8 The BCD code for this character is 778 in some BCD variants The groupmark was proposed for Unicode standardization in 2015 9 and was assigned to value U 2BD2 GROUP MARK Functionally this corresponds to the EBCDIC IGS character ASCII GS X 1D It is now in Unicode 10 0 at this position but only the Symbola and Unifont fonts support it The Wordmark by contrast is not a BCD character Rather it is a flag bit used to mark the end of a word on some variable word length computers such as the IBM 1401 BCD code variations editThere are many different versions of the six bit BCD code There are three major categories of difference The mapping from zone punches to high order bits All codes translate no zone punches to a bit pattern of 00 but some encode the zone punches in 12 11 0 order preserving alphabetical order while others use 0 11 12 order resulting in a partially reversed alphabet The handling of the digit 0 The straightforward translation from punched form would place the blank before digits 1 9 and encode 0 at the start of the line with S in it All codes have some special case handling which either translates the digit 0 to the all zero binary code and moves the blank elsewhere or gives it binary code 001010 decimal 10 and moves the 8 2 punch elsewhere The assignment of special characters The characters assigned to codes beyond the basic alphanumeric set varied widely even within one model of computer In Spanish speaking countries the character N did not exist in the original system therefore was chosen by most manufacturers Bull NCR and Control Data but there was an inconsistency when merging databases to 7 bit ASCII code for in that coding system the character was chosen resulting in two different codes for the same character Examples of BCD codes editThe following charts show the numeric values of BCD characters in hexadecimal base 16 notation as that most clearly reflects the structure of 4 bit binary coded decimal plus two extra bits For example the code for A in row 3x and column x1 is hexadecimal 31 or binary 11 0001 Tape style edit 48 character BCD code edit The first versions of BCDIC had 48 characters as they were based on card punch patterns and the character sets of printers neither of which encouraged having a power of two number of characters IBM 48 character BCDIC code 1 68 x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF0x space 1 2 3 4 5 6 7 8 9 0 1x S T U V W X Y Z 2x J K L M N O P Q R 3x amp A B C D E F G H I This was based on a 40 character punched card code the original 37 10 digits 26 letters and blank plus three commercially important characters added around 1932 1 67 hyphen minus used for printing credit balances and hyphenated names the ampersand also used in many names and addresses Procter amp Gamble Mr amp Mrs Smith and the asterisk used to overprint unused fields when printing cheques IBM 1401 BCD code edit Rather than following the IBM 704 s storage representation IBM 1401 followed the tape representation descended from the 48 character BCD thus using the all zero code for blank and the code 10 0x0A for the digit zero It had defined character forms for all possible values for documentation purposes 10 but only 48 of the 63 non blank characters were printable and there was considerable variation in how the other code values shaded in the table below were depicted in practice Even the other characters varied between different available print chains for the IBM 1403 printer x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF0x space 1 2 3 4 5 6 7 8 9 0 gt 1x S T U V W X Y Z 2x J K L M N O P Q R D3x amp A B C D E F G H I lt Code page 353 edit The BCDIC A Code page was assigned as Code page 353 also known as CP353 Some of the characters in this code page are not in Unicode The duplication of can be found in IBM s own documentation and is not a mistake here 11 x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF0x space 1 2 3 4 5 6 7 8 9 0 gt 1x S T U V W X Y Z g 2x J K L M N O P Q R D3x amp A B C D E F G H I lt At 0x1A is the record mark At 0x3F is the group mark PTTC BCD code pages edit PTTC BCD had 5 options There were five code pages They are shown below The PTTC BCD Standard Option was assigned as Code page 355 or CP355 x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF0x space 1 2 3 4 5 6 7 8 9 0 1x S T U V W X Y Z g2x J K L M N O P Q R lt 3x amp A B C D E F G H I The PTTC BCD H Option was assigned as Code page 357 or CP357 x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF0x space 1 2 3 4 5 6 7 8 9 0 1x S T U V W X Y Z 2x J K L M N O P Q R 3x A B C D E F G H I The PTTC BCD Correspondence Option was assigned as Code page 358 or CP358 x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF0x space 1 2 3 4 5 6 7 8 9 0 1x S T U V W X Y Z 2x J K L M N O P Q R lt 3x A B C D E F G H I gt The PTTC BCD Monocase Option was assigned as Code page 359 or CP359 x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF0x space 1 2 3 4 5 6 7 8 9 0 1x S T U V W X Y Z 2x J K L M N O P Q R 3x amp A B C D E F G H I The PTTC BCD Duocase Option was assigned as Code page 360 or CP360 x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF0x space 1 2 3 4 5 6 7 8 9 0 1x S T U V W X Y Z 2x J K L M N O P Q R 3x amp A B C D E F G H I IBM 704 storage style edit IBM 704 BCD code edit The IBM 704 reordered the BCDIC code to allow a normal alphabetic collating order internally with 0 before 1 and A before Z It could automatically translate between this internal form and the earlier BCDIC when reading and writing magnetic tapes 12 35 The following table shows the code assignments for the IBM 704 computer Unassigned code positions appear as blanks 12 35 IBM 704 character set x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF0x 0 1 2 3 4 5 6 7 8 9 1x amp A B C D E F G H I 0 2x J K L M N O P Q R 0 3x space S T U V W X Y Z 0 and 0 were rarely used characters that corresponded to the punched card convention of a digit 0 with an overpunched sign in rows 12 or 11 The following table shows the code assignments for the type 716 printer used starting with the IBM 704 computer and through the 7094 12 58 The 704 interface b sent virtual punched card rows to this printer two words 72 bits at a time so the mapping from 6 bit BCD characters was done by software and was not built into the printer IBM 716 printer character set G x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF0x 1 2 3 4 5 6 7 8 9 1x A B C D E F G H I 2x J K L M N O P Q R 3x 0 S T U V W X Y Z This is a repertoire of 45 characters not counting blank which is handled specially by the printer as the characters and are duplicated Fortran character set edit There was some variation IBM 704 Fortran had a different set of special characters preserving only the duplicated minus sign 13 IBM 716 printer Fortran character set x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF0x 1 2 3 4 5 6 7 8 9 1x A B C D E F G H I 2x J K L M N O P Q R 3x 0 S T U V W X Y Z A similar code was used for the IBM 709 7090 and 7094 successors 14 but with some of the special characters reassigned IBM 7090 7094 character set x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF0x 0 1 2 3 4 5 6 7 8 9 1x amp A B C D E F G H I 0 2x J K L M N O P Q R 0 3x space S T U V W X Y Z GBCD code edit Below is the table of GE Honeywell s GBCD code a variant of BCD 15 x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF0x 0 1 2 3 4 5 6 7 8 9 gt 1x space A B C D E F G H I amp lt 2x J K L M N O P Q R 3x S T U V W X Y Z Burroughs B5500 BCD code edit The following table shows the code assignments for the Burroughs B5500 computer sometimes referred to as BIC Burroughs Interchange Code 16 x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF0x 0 1 2 3 4 5 6 7 8 9 gt 1x A B C D E F G H I amp lt 2x J K L M N O P Q R 3x space S T U V W X Y Z See also editBinary coded decimal Six bit character code EBCDIC SQUOZENotes edit There are actually multiple card codes e g by 1964 there were ten versions of the IBM 026 with slightly different character sets The interface on e g the 7090 is different although the software still must do mapping References edit a b c d e Mackenzie Charles E 1980 Coded Character Sets History and Development PDF The Systems Programming Series 1 ed Addison Wesley Publishing Company Inc ISBN 0 201 14460 3 LCCN 77 90165 Archived PDF from the original on 2016 05 26 Retrieved 2017 04 22 1 Pugh Emerson W Heide Lars STARS Punched Card Equipment IEEE Global History Network Archived from the original on 2012 05 11 Retrieved 2012 06 09 Pugh Emerson W 1995 Building IBM Shaping and Industry and Its Technology MIT Press pp 50 51 ISBN 978 0 262 16147 3 Jones Douglas W Punched Card Codes Retrieved 2014 01 01 Burroughs B5500 Information Processing Systems Reference Manual PDF Burroughs Corporation 1964 Archived from the original PDF on 2020 07 29 Retrieved 2012 06 08 Control Data Corporation 1965 Codes Control Data 6600 Computer System PDF Record mark Encyclopedia PC Magazine Retrieved 2016 04 09 group mark Encyclopedia com Retrieved 2016 04 09 Shirriff Ken Proposal for addition of Group Mark symbol PDF unicode org Retrieved 2016 04 09 IBM 1401 Data Processing System Reference Manual PDF IBM April 1962 p 170 A24 1403 5 Archived from the original PDF on 2012 03 14 Systems i Software Globalization cp00353z PDF www 03 ibm com Archived from the original PDF on 2013 01 21 Retrieved 2022 06 30 a b c IBM 704 electronic data processing machine manual of operation PDF IBM 1955 pp 35 58 Form 24 6661 2 Retrieved 2017 04 22 Fortran Automatic Coding System for the IBM 704 PDF IBM 1956 10 15 p 49 Retrieved 2015 09 15 Harper Jack 2001 08 21 IBM 7090 94 Character Representation Retrieved 2017 04 22 Section Tables of characters in BULL computers PDF Archived from the original PDF on 2011 07 08 Retrieved 2010 11 15 Burroughs B 5500 Information Processing Systems Extended Algol Reference Manual PDF 1966 p B 1 Further reading editOperating System GCOS 8 Operating System Programmer s Guide Bull NovaScale 9000 Series Assembly Instructions GCOS 8 PDF Bull S A CEDOC November 2003 67 A2 RJ78 REV00 Archived from the original PDF on 2015 02 12 Bonten Jo H M 2009 03 08 2007 Data formats in old 48 and 36 bits computers Six bits characters Geldrop Netherlands Archived from the original on 2016 06 16 Retrieved 2016 06 16 Retrieved from https en wikipedia org w index php title BCD character encoding amp oldid 1213749174, wikipedia, wiki, book, books, library,

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