Indian Script Code for Information Interchange

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Indian Standard Code for Information Interchange (ISCII) is a coding scheme for representing various writing systems of India. It encodes the main Indic scripts and a Roman transliteration. The supported scripts are: Assamese, Bengali (Bengla), Devanagari, Gujarati, Gurmukhi, Kannada, Malayalam, Oriya, Tamil, and Telugu. ISCII does not encode the writing systems of India based on Arabic, but its writing system switching codes nonetheless provide for Kashmiri, Sindhi, Urdu, Persian, Pashto and Arabic. The Arabic-based writing systems were subsequently encoded in the PASCII encoding.

The Brahmi-derived writing systems are mostly rather similar in structure, but have different letter shapes. So ISCII encodes letters with the same phonetic value at the same codepoint, overlaying the various scripts. For example, the ISCII codes 0xB3 0xDB represent [ki]. This will be rendered as कि in Devanagari, as ਕਿ in Gurmukhi, and as கி in Tamil. The writing system can be selected in rich text by markup or in plain text by means of the ATR code described below.

One motivation for the use of a single encoding is the idea that it will allow easy transliteration from one writing system to another. However, there are enough incompatibilities that this is not really a practical idea. See About ISCII.

ISCII is an 8-bit encoding. The lower 128 codepoints are plain ASCII, the upper 128 codepoints are ISCII-specific. In addition to the codepoints representing characters, ISCII makes use of a codepoint with mnemonic ATR that indicates that the following byte contains one of two kinds of information. One set of values changes the writing system until the next writing system indicator or end-of-line. Another set of values select display modes such as bold and italic. ISCII does not provide a means of indicating the default writing system.

ISCII has not been widely used outside of certain government institutions and has now been rendered largely obsolete by Unicode. Unicode uses a separate block for each Indic writing system, and largely preserves the ISCII layout within each block.

Codepage layout[edit]

The following table shows the character set for Devanagari. The code sets for Assamese, Bengali, Gujarati, Gurmukhi, Kannada, Malayalam, Oriya, Tamil, and Telugu are similar, with each Devanagari form replaced by the equivalent form in each writing system. Each character is shown with its decimal code and its Unicode equivalent.

ISCII Devanagari
—0 —1 —2 —3 —4 —5 —6 —7 —8 —9 —A —B —C —D —E —F
 
0_
 
NUL
0000
0
SOH
0001
1
STX
0002
2
ETX
0003
3
EOT
0004
4
ENQ
0005
5
ACK
0006
6
BEL
0007
7
BS
0008
8
HT
0009
9
LF
000A
10
VT
000B
11
FF
000C
12
CR
000D
13
SO
000E
14
SI
000F
15
 
1_
 
DLE
0010
16
DC1
0011
17
DC2
0012
18
DC3
0013
19
DC4
0014
20
NAK
0015
21
SYN
0016
22
ETB
0017
23
CAN
0018
24
EM
0019
25
SUB
001A
26
ESC
001B
27
FS
001C
28
GS
001D
29
RS
001E
30
US
001F
31
 
2_
 
SP
0020
32
!
0021
33
"
0022
34
#
0023
35
$
0024
36
%
0025
37
&
0026
38
'
0027
39
(
0028
40
)
0029
41
*
002A
42
+
002B
43
,
002C
44
-
002D
45
.
002E
46
/
002F
47
 
3_
 
0
0030
48
1
0031
49
2
0032
50
3
0033
51
4
0034
52
5
0035
53
6
0036
54
7
0037
55
8
0038
56
9
0039
57
:
003A
58
;
003B
59
<
003C
60
=
003D
61
>
003E
62
?
003F
63
 
4_
 
@
0040
64
A
0041
65
B
0042
66
C
0043
67
D
0044
68
E
0045
69
F
0046
70
G
0047
71
H
0048
72
I
0049
73
J
004A
74
K
004B
75
L
004C
76
M
004D
77
N
004E
78
O
004F
79
 
5_
 
P
0050
80
Q
0051
81
R
0052
82
S
0053
83
T
0054
84
U
0055
85
V
0056
86
W
0057
87
X
0058
88
Y
0059
89
Z
005A
90
[
005B
91
\
005C
92
]
005D
93
^
005E
94
_
005F
95
 
6_
 
`
0060
96
a
0061
97
b
0062
98
c
0063
99
d
0064
100
e
0065
101
f
0066
102
g
0067
103
h
0068
104
i
0069
105
j
006A
106
k
006B
107
l
006C
108
m
006D
109
n
006E
110
o
006F
111
 
7_
 
p
0070
112
q
0071
113
r
0072
114
s
0073
115
t
0074
116
u
0075
117
v
0076
118
w
0077
119
x
0078
120
y
0079
121
z
007A
122
{
007B
123
|
007C
124
}
007D
125
~
007E
126
DEL
007F
127
 
8_
 
 
9_
 
 
A_
 

0901
161

0902
162

0903
163

0905
164

0906
165

0907
166

0908
167

0909
168

090A
169

090B
170

090E
171

090F
172

0910
173

090D
174

0912
175
 
B_
 

0913
176

0914
177

0911
178

0915
179

0916
180

0917
181

0918
182

0919
183

091A
184

091B
185

091C
186

091D
187

091E
188

091F
189

0920
190

0921
191
 
C_
 

0922
192

0923
193

0924
194

0925
195

0926
196

0927
197

0928
198

0929
199

092A
200

092B
201

092C
202

092D
203

092E
204

092F
207

095F
206

0930
205
 
D_
 

0931
208

0932
209

0933
210

0934
211

0935
212

0936
213

0937
214

0938
215

0939
216
INV

217

093E
218
ि
093F
219

0940
220

0941
221

0942
222

0943
223
 
E_
 

0946
224

0947
225

0948
226

0945
227

094A
228

094B
229

094C
230

0949
231

094D
232

093C
233

0964
234
ATR

239
 
F_
 
EXT

240

0966
241

0967
242

0968
243

0969
244

096A
245

096B
246

096C
247

096D
248

096E
249

096F
250

Special code points[edit]

ii

INV character—code point D9 (217)
The INV character is used as a pseudo-consonant to display combining elements in isolation. For example, क (ka) + ् (halant) + INV = क्‍ (half ka). The Unicode equivalent is no break space 00A0 or dotted circle ◌ 25CC.
ATR character—code point EF (239)
The ATR character followed by a byte code is used to switch to a different font attribute (such as bold) or language (such as Bengali), up to the next ATR sequence or the end of the line. This has no direct Unicode equivalent, as font attributes are not part of Unicode, and each script has a distinct set of code points.
EXT character—code point F0 (240)
The EXT character followed by a byte code indicates a Vedic accent. This has no direct Unicode equivalent, as Vedic accents are assigned to distinct code points.
Halant character ़—code point E8 (232)
The halant character removes the implicit vowel from a consonant and is used between consonants to represent conjunct consonants. For example, क (ka) + ् (halant) + त (ta) = क्त (kta). The sequence ् (halant) + ् (halant) displays a conjunct with an explicit halant, for example क (ka) + ् (halant) + ् (halant) + त (ta) = क्‌त. The sequence ् (halant) + ़ (nukta) displays a conjunct with half consonants, if available, for example क (ka) + ् (halant) + ़ (nukta) + त (ta) = क्‍त.
ISCII Unicode
single halant E8 halant 094D
halant + halant E8 E8 halant + ZWNJ 094D 200C
halant + nukta E8 E9 halant + ZWJ 094D 200D
Nukta character ़—code point E9 (233)
The nukta character after another ISCII character is used for a number of rarer characters which don't exist in the main ISCII set. For example क (ka) + ़ (nukta) = क़ (qa). These characters have precomposed forms in Unicode, as shown in the following table.
ISCII
code point
Original
character
Character
with nukta
Unicode
code point
A1 (161) 0950
A6 (166) 090C
A7 (167) 0961
AA (176) 0960
B3 (179) क़ 0958
B4 (180) ख़ 0959
B5 (181) ग़ 095A
BA (186) ज़ 095B
BF (191) ड़ 095C
C0 (192) ढ़ 095D
C9 (201) फ़ 095E
DB (219) ि 0962
DC (220) 0963
DF (223) 0944
EA (234) 093D

Code pages for ISCII conversion[edit]

To convert from Unicode (UTF-8) to an ISCII / ANSI coding, the following code pages may be used:

 * 57002 Devanagari (Hindi, Marathi, Sanskrit, Konkani)
 * 57003 Bengali
 * 57004 Tamil
 * 57005 Telugu
 * 57006 Assamese (same as Bengali)
 * 57007 Oriya
 * 57008 Kannada
 * 57009 Malayalam
 * 57010 Gujarati
 * 57011 Punjabi (Gurmukhi)

Code points for all languages[edit]

Each alphabet is listed in the order of its ISCII code point. Code points with asterisks (*) indicate the code point followed by nukta, e.g. क (ka) + ़ = क़ (qa); इ (i) + ़ = ऌ (ḷ). Each character is listed along with its Unicode code point.

External links[edit]