Sunday, September 13, 2009

EBCDIC CODE

EBCDIC CODE
EBCDIC was devised in 1963 and 1964 by IBM and was announced with the release of the IBM System/360 line of mainframe computers. It was created to extend the Binary-Coded Decimal encoding that existed at the time. It is an 8-bit character encoding, in contrast to, and developed separately from, the 7-bit ASCII encoding scheme.

While IBM was a chief proponent of the ASCII standardization committee, they did not have time to prepare ASCII peripherals (such as card punch machines) to ship with its System/360 computers, so the company settled on EBCDIC at the time. The System/360 became wildly successful, and thus so did EBCDIC.

All IBM mainframe peripherals and operating systems (except Linux on zSeries or iSeries) use EBCDIC as their inherent encoding,[1] but software can translate to and from other encodings. Many hardware peripherals provide translation as well and modern mainframes (such as IBM zSeries) include processor instructions, at the hardware level, to accelerate translation between character sets.

At the time it was devised, EBCDIC made it relatively easy to enter data into a computer with punch cards. Since punch cards are no longer used on mainframes, EBCDIC is used in modern mainframes primarily for backwards compatibility. It does have an advantage of limiting the number of hole punches per column to 2 holes for uppercase and numbers, which increases the durability of these punch cards as they are handled by a card reader. This encoding is also known as Hollerith code. [2]

EBCDIC has no modern technical advantage over ASCII-based code pages such as the ISO-8859 series or Unicode. There are some technical niceties in each, e.g., ASCII and EBCDIC both have one bit which indicates upper or lower case. But there are some aspects of EBCDIC which make it much less pleasant to work with than ASCII (such as a non-contiguous alphabet). As with single-byte extended ASCII codepages, most EBCDIC codepages only allow up to 2 languages (English and one other language) to be used in a database or text file.

Where true support for multilingual text is desired, a system supporting far more characters is needed. Generally this is done with some form of Unicode support. There is an EBCDIC Unicode Transformation Format called UTF-EBCDIC proposed by the Unicode consortium, but it is not intended to be used in open interchange environments and, even on EBCDIC-based systems, it is almost never used. IBM mainframes support UTF-16, but they do not support UTF-EBCDIC natively.

Arabic EBCDIC versions are typically in presentation order, in left to right order as displayed by an older mainframe or line printer, rather than in the right to left logical order used by modern encodings such as Unicode.


EBCDIC Table



Dec Hex Code Dec Hex Code Dec Hex Code Dec Hex Code
0 00 NUL 32 20
64 40 space 96 60 -
1 01 SOH 33 21
65 41
97 61 /
2 02 STX 34 22
66 42
98 62
3 03 ETX 35 23
67 43
99 63
4 04
36 24
68 44
100 64
5 05 HT 37 25 LF 69 45
101 65
6 06
38 26 ETB 70 46
102 66
7 07 DEL 39 27 ESC 71 47
103 67
8 08
40 28
72 48
104 68
9 09
41 29
73 49
105 69
10 0A
42 2A
74 4A [ 106 6A |
11 0B VT 43 2B
75 4B . 107 6B ,
12 0C FF 44 2C
76 4C < 108 6C %
13 0D CR 45 2D ENQ 77 4D ( 109 6D _
14 0E SO 46 2E ACK 78 4E + 110 6E >
15 0F SI 47 2F BEL 79 4F | ! 111 6F ?
16 10 DLE 48 30
80 50 & 112 70
17 11
49 31
81 51
113 71
18 12
50 32 SYN 82 52
114 72
19 13
51 33
83 53
115 73
20 14
52 34
84 54
116 74
21 15
53 35
85 55
117 75
22 16 BS 54 36
86 56
118 76
23 17
55 37 EOT 87 57
119 77
24 18 CAN 56 38
88 58
120 78
25 19 EM 57 39
89 59
121 79
26 1A
58 3A
90 5A ! ] 122 7A :
27 1B
59 3B
91 5B $ 123 7B #
28 1C IFS 60 3C
92 5C * 124 7C @
29 1D IGS 61 3D NAK 93 5D ) 125 7D
30 1E IRS 62 3E
94 5E ; 126 7E =
31 1F IUS 63 3F SUB 95 5F ^ 127 7F "
Dec Hex Code Dec Hex Code Dec Hex Code Dec Hex Code
128 80
160 A0
192 C0 { 224 E0 \
129 81 a 161 A1 ~ 193 C1 A 225 E1
130 82 b 162 A2 s 194 C2 B 226 E2 S
131 83 c 163 A3 t 195 C3 C 227 E3 T
132 84 d 164 A4 u 196 C4 D 228 E4 U
133 85 e 165 A5 v 197 C5 E 229 E5 V
134 86 f 166 A6 w 198 C6 F 230 E6 W
135 87 g 167 A7 x 199 C7 G 231 E7 X
136 88 h 168 A8 y 200 C8 H 232 E8 Y
137 89 i 169 A9 z 201 C9 I 233 E9 Z
138 8A
170 AA
202 CA
234 EA
139 8B
171 AB
203 CB
235 EB
140 8C
172 AC
204 CC
236 EC
141 8D
173 AD
205 CD
237 ED
142 8E
174 AE
206 CE
238 EE
143 8F
175 AF
207 CF
239 EF
144 90
176 B0
208 D0 } 240 F0 0
145 91 j 177 B1
209 D1 J 241 F1 1
146 92 k 178 B2
210 D2 K 242 F2 2
147 93 l 179 B3
211 D3 L 243 F3 3
148 94 m 180 B4
212 D4 M 244 F4 4
149 95 n 181 B5
213 D5 N 245 F5 5
150 96 o 182 B6
214 D6 O 246 F6 6
151 97 p 183 B7
215 D7 P 247 F7 7
152 98 q 184 B8
216 D8 Q 248 F8 8
153 99 r 185 B9
217 D9 R 249 F9 9
154 9A
186 BA
218 DA
250 FA
155 9B
187 BB
219 DB
251 FB
156 9C
188 BC
220 DC
252 FC
157 9D
189 BD
221 DD
253 FD
158 9E
190 BE
222 DE
254 FE
159 9F
191 BF
223 DF
255 FF

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