Sixbit refers to various character codes designed for use on computers with word lengths a multiple of 6. There are 64 possible codes, so sixbit codes generally include only the upper-case letters, the numerals, a collection of punctuation characters, and sometimes control characters.

[edit] Types of sixbit code pages

  • Alphanumeric Binary-coded decimal (BCD), used by IBM. This was replaced by the 8-bit EBCDIC code when System/360 standardized on 8-bit bytes. There are some variants of such code page (see below).
  • Digital Equipment Corporation sixbit. This is simply the ASCII character codes from 32 to 95 coded as 0 to 63; it includes the space, punctuation characters, numbers, and uppercase letters, but no control characters. Since it included no control characters (not even end-of-line), it was not used for general text processing, but only for names such as filenames and assembler symbols.
  • Fieldata, used by UNIVAC's 1100-series computers. These systems used a 36-bit word (capable of storing 6 Fieldata characters).

[edit] Examples of BCD sixbit code pages

CDC 1604 : Magnetic tape BCD codes

.0 .1 .2 .3 .4 .5 .6 .7 .8 .9 .A .B .C .D .E .F
0. 1 2 3 4 5 6 7 8 9 0 # @ tape
mark
1. space / S T U V W X Y Z record
mark		 ,  %
2. − J K L M N O P Q R −0 $ *
3. & A B C D E F G H I +0 . ¤ group
mark

CDC 1604 : Punched card codes

.0 .1 .2 .3 .4 .5 .6 .7 .8 .9 .A .B .C .D .E .F
0. 1 2 3 4 5 6 7 8 9 0 = −
1. space / S T U V W X Y Z , (
2. --- J K L M N O P Q R −0 $ *
3. + A B C D E F G H I +0 . )

CDC 1612 printer codes (business applications)

.0 .1 .2 .3 .4 .5 .6 .7 .8 .9 .A .B .C .D .E .F
0.  : 1 2 3 4 5 6 7 8 9 0 = ≠ ≤  ! [
1. space / S T U V W X Y Z ] , ( → ≡ ~
2. − J K L M N O P Q R  % $ * ↑ ↓ >
3. + A B C D E F G H I < . ) ≥  ?  ;

[edit] External links