Close menu

CDC display code


Source: http://en.wikipedia.org/wiki/CDC_display_code
Updated: 2015-11-06T22:52Z

Display code is the six-bit character code used by many computer systems manufactured by Control Data Corporation, notably the CDC3000 series and the following CDC 6000 series in 1964. The CDC 6000 series, and their followons, had 60 bit words. As such, typical usage packed 10 characters per word.

There were several variations of display code, notably the 63-character character set, and the 64-character character set. There were also 'CDC graphic' and 'ASCII graphic' variants of both the 63- and 64-character sets. The choice between 63- or 64-character character set, and between CDC or ASCII graphic was site-selectable. Generally, early CDC customers started out with the 63-character character set, and CDC graphic print trains on their line printers. As time-sharing became prevalent, almost all sites used the ASCII variant - so that line printer output would match interactive usage. Later CDC customers were also more likely to use the 64-character character set.

A later variation, called 6/12 display code, was used in the Kronos and NOS timesharing systems in order to support full ASCII capabilities. In 6/12 mode, an escape character (the circumflex, octal 76) would indicate that the following letter was lower case. Thus, upper case and other characters were 6 bits in length, and lower case characters were 12 bits in length.

The PLATO system used a further variant of 6/12 display code. Noting that lower case letters were most common in typical PLATO usage, the roles were reversed. Lower case letters were the norm, and the escape character preceded upper case letters.

The typical text file format used a zero-byte terminator to signify the end of each record. The zero-byte terminator was indicated by, at least, the final twelve bits of a 60-bit word being set to zero.[1] The terminator could actually be anywhere from 12- to 66-bits long - depending on the length of the record. This caused an ambiguity in the 64-character character set, when a colon character needed to be the final character in a record. In such cases a blank character was typically appended to the record after the trailing colon.

Display code characters (64-character character set version)

ASCIICDC
BinaryDecimalOctalGraphicGraphicName
000 000000 : :colon[2]
000 001101AA
000 010202BB
000 011303CC
000 100404DD
000 101505EE
000 110606FF
000 111707GG
001 000810HH
001 001911II
001 0101012JJ
001 0111113KK
001 1001214LL
001 1011315MM
001 1101416NN
001 1111517OO
010 0001620PP
010 0011721QQ
010 0101822RR
010 0111923SS
010 1002024TT
010 1012125UU
010 1102226VV
010 1112327WW
011 0002430XX
011 0012531YY
011 0102632ZZ
011 011273300
011 100283411
011 101293522
011 110303633
011 111313744
ASCIICDC
BinaryDecimalOctalGraphicGraphicName
100 000324055
100 001334166
100 010344277
100 011354388
100 100364499
100 1013745++
100 1103846--
100 1113947**
101 0004050//
101 0014151((
101 0104252))
101 0114353$$
101 1004454==
101 1014555  blank
101 1104656,,
101 1114757..
110 0004860#equiv
110 0014961[[
110 0105062]]
110 0115163 % %[3]
110 1005264"not eq
110 1015365_concat[4]
110 1105466 !log OR
110 1115567&log AND
111 0005670'super
111 0015771 ?sub[5]
111 0105872<<
111 0115973>>
111 1006074@
111 1016175\
111 1106276^¬NOT
111 1116377 ; ;
  1. ^ CDC often used the term byte to refer to 12-bit quantities, even though characters were only 6-bits long.
  2. ^ Display code 00 has no associated graphic in the 63-character set
  3. ^ Display code 63 (octal) is a : (colon) in the 63-character set
  4. ^ In CDC PASCAL, this is the left brace, {, character
  5. ^ In CDC PASCAL, this is the right brace, }, character

6/12 display code

The NOS 6/12 display code is one of the character sets used on CDC Cyber NOS computers to represent all ASCII characters.

ASCIIdisplay code
DecHexAbbrDecOct6/12
000NUL62 3276 40^5
101SOH62 3376 41^6
202STX62 3476 42^7
303ETX62 3576 43^8
404EOT62 3676 44^9
505ENQ62 3776 45^+
606ACK62 3876 46^-
707BEL62 3976 47^*
808BS62 4076 50^/
909HT62 4176 51^(
100ALF62 4276 52^)
110BVT62 4376 53^$
120CFF62 4476 54^=
130DCR62 4576 55
140ESO62 4676 56^,
150FSI62 4776 57^.
1610DLE62 4876 60^#
1711DC162 4976 61^[
1812DC262 5076 62^]
1913DC362 5176 63^%
2014DC462 5276 64^"
2115NAK62 5376 65^_
2216SYN62 5476 66^!
2317ETB62 5576 67^&
2418CAN62 5676 70^'
2519EM62 5776 71^?
261ASUB62 5876 72^<
271BESC62 5976 73^>
281CFS62 6076 74^@
291DGS62 6176 75^\
301ERS62 6276 76^^
311FUS62 6376 77^;
ASCIIdisplay code
DecHexGlyphDecOct6/12
32204555
3321!5466 !
3422"5264"
3523#4860#
3624$4353$
3725%5163 %
3826&5567&
3927'5670'
4028(4151(
4129)4252)
422A*3947*
432B+3745+
442C,4656,
452D-3846-
462E.4757.
472F/4050/
4830027330
4931128341
5032229352
5133330363
5234431374
5335532405
5436633416
5537734427
5638835438
5739936449
583A:60 474 04@D
593B;6377 ;
603C<5872<
613D=4454=
623E>5973>
633F?5771 ?
ASCIIdisplay code
DecHexGlyphDecOct6/12
6440@60 174 01@A
6541A101A
6642B202B
6743C303C
6844D404D
6945E505E
7046F606F
7147G707G
7248H810H
7349I911I
744AJ1012J
754BK1113K
764CL1214L
774DM1315M
784EN1416N
794FO1517O
8050P1620P
8151Q1721Q
8252R1822R
8353S1923S
8454T2024T
8555U2125U
8656V2226V
8757W2327W
8858X2430X
8959Y2531Y
905AZ2632Z
915B[4961[
925C\6175\
935D]5062]
945E^60 274 02@B
955F_5365_
ASCIIdisplay code
DecHexGlyphDecOct6/12
9660`60 774 07@G
9761a62 176 01^A
9862b62 276 02^B
9963c62 376 03^C
10064d62 476 04^D
10165e62 576 05^E
10266f62 676 06^F
10367g62 776 07^G
10468h62 876 10^H
10569i62 976 11^I
1066Aj62 1076 12^J
1076Bk62 1176 13^K
1086Cl62 1276 14^L
1096Dm62 1376 15^M
1106En62 1476 16^N
1116Fo62 1576 17^O
11270p62 1676 20^P
11371q62 1776 21^Q
11472r62 1876 22^R
11573s62 1976 23^S
11674t62 2076 24^T
11775u62 2176 25^U
11876v62 2276 26^V
11977w62 2376 27^W
12078x62 2476 30^X
12179y62 2576 31^Y
1227Az62 2676 32^Z
1237B{62 2776 33^0
1247C|62 2876 34^1
1257D}62 2976 35^2
1267E~62 3076 36^3
1277FDEL62 3176 37^4

External links

Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.

Also On Wow

    Advertisement

    Trending Now