ITU T.50

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ITU-T recommendation T.50 specifies the International Reference Alphabet (IRA), formerly International Alphabet No. 5 (IA5), a character encoding. ASCII is the U.S. variant of that character set.

ITU-T technical Commitee of the ITU

The ITU Telecommunication Standardization Sector (ITU-T) is one of the three sectors of the International Telecommunication Union (ITU); it coordinates standards for telecommunications.

Character encoding is used to represent a repertoire of characters by some kind of encoding system. Depending on the abstraction level and context, corresponding code points and the resulting code space may be regarded as bit patterns, octets, natural numbers, electrical pulses, etc. A character encoding is used in computation, data storage, and transmission of textual data. "Character set", "character map", "codeset" and "code page" are related, but not identical, terms.

ASCII American computer character encoding

ASCII, abbreviated from American Standard Code for Information Interchange, is a character encoding standard for electronic communication. ASCII codes represent text in computers, telecommunications equipment, and other devices. Most modern character-encoding schemes are based on ASCII, although they support many additional characters.

Contents

The original version from November 1988 corresponds to ISO 646. The current version is from September 1992.

History

At the beginning was the International Telegraph Alphabet No. 2 (ITA2), a five bits code. IA5 is an improvement based on seven bits bytes.

Use

This standard is referenced by other standards such as RFC 3966. It is also used by some analog modems such as Cisco ones. [4]

This standard is referenced by other standards such as RFC 3939 - Calling Line Identification for Voice Mail Messages.

Character Set

IA5 Character Set
_0_1_2_3_4_5_6_7_8_9_A_B_C_D_E_F
0_
0
NUL
0000
SOH
0001
STX
0002
ETX
0003
EOT
0004
ENQ
0005
ACK
0006
BEL
0007
BS
0008
HT
0009
LF
000A
VT
000B
FF
000C
CR
000D
SO
000E
SI
000F
1_
16
DLE
0010
DC1
0011
DC2
0012
DC3
0013
DC4
0014
NAK
0015
SYN
0016
ETB
0017
CAN
0018
EM
0019
SUB
001A
ESC
001B
FS
001C
GS
001D
RS
001E
US
001F
2_
32
SP
0020
!
0021
"
0022
#
 
$
 
%
0025
&
0026
'
0027
(
0028
)
0029
*
002A
+
002B
,
002C
-
002D
.
002E
/
002F
3_
48
0
0030
1
0031
2
0032
3
0033
4
0034
5
0035
6
0036
7
0037
8
0038
9
0039
:
003A
;
003B
<
003C
=
003D
>
003E
?
003F
4_
64
@
 
A
0041
B
0042
C
0043
D
0044
E
0045
F
0046
G
0047
H
0048
I
0049
J
004A
K
004B
L
004C
M
004D
N
004E
O
004F
5_
80
P
0050
Q
0051
R
0052
S
0053
T
0054
U
0055
V
0056
W
0057
X
0058
Y
0059
Z
005A
[
 
\
 
]
 
^
 
_
005F
6_
96
`
 
a
0061
b
0062
c
0063
d
0064
e
0065
f
0066
g
0067
h
0068
i
0069
j
006A
k
006B
l
006C
m
006D
n
006E
o
006F
7_
112
p
0070
q
0071
r
0072
s
0073
t
0074
u
0075
v
0076
w
0077
x
0078
y
0079
z
007A
{
 
|
 
}
 
~
 
DEL
007F

Standardisation

See also

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References

  1. 1 2 3 4 Salste, Tuomas (January 2016). "7-bit character sets: Revisions of ASCII". Aivosto Oy. urn:nbn:fi-fe201201011004 . Archived from the original on 2016-06-13. Retrieved 2016-06-13.
  2. 1 2 3 4 International Alphabet No. 5 - Recommendation T.50, International Telecommunication Union (ITU) - The International Telegraph and Telephone Consultative Committee (CCITT) - Series T: Terminal Equipment and Protocols for Telematic Services, 1993-04-16 [1988-11-25], E 33116, archived from the original on 2017-03-19, retrieved 2017-03-18
  3. International Reference Alphabet (IRA) - Information Technology - 7-bit Coded Character Set For Information Interchange - Recommendation T.50, International Telecommunication Union (ITU) - The International Telegraph and Telephone Consultative Committee (CCITT) - Terminal Equipment and Protocols for Telematic Services, 1993-04-16 [1992-09-18], E 3177, archived from the original on 2014-12-19, retrieved 2017-03-18
  4. "AT Command Set and Register Summary for NM-8AM-V2, NM-16AM-V2, WIC-1AM, and WIC-2AM Analog Modem WAN Interface Cards - 2: Syntax and Procedures [Cisco 3600 Series Multiservice Platforms] - Cisco Systems". Cisco.com. Archived from the original on 2011-09-07. Retrieved 2012-10-03.