RADIX50 Character Code Reference 

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RADIX50 is a character coding system used in earlier Digital Equipment Corporation computers, such as the PDP-10, DECsystem-10 and DECsystem-20. It was implemented as a way to pack as many characters into as few bits as possible.

RADIX50 actually contains 40 codes, or 50 in octal. Because this is not a power of two, the PDP-10 processor had instructions to pack several RADIX-50 words into a single 36-bit word or extract RADIX-50 words from a 36-bit word. The assignments are shown in the following table.

Least Significant Bits
0
0000
[00]
1
0001
[01]
2
0010
[02]
3
0011
[03]
4
0100
[04]
5
0101
[05]
6
0110
[06]
7
0111
[07]
M
o
s
t

S
i
g
n
i
f
i
c
a
n
t

B
i
t
s

0
000
[00]
SP
(0)
00
[00]
0
(1)
01
[01]
1
(2)
02
[02]
2
(3)
03
[03]
3
(4)
04
[04]
4
(5)
05
[05]
5
(6)
06
[06]
6
(7)
07
[07]

1
001
[10]
7
(8)
08
[10]
8
(9)
09
[11]
9
(10)
0A
[12]
A
(11)
0B
[13]
B
(12)
0C
[14]
C
(13)
0D
[15]
D
(14)
0E
[16]
E
(15)
0F
[17]

2
010
[20]
F
(16)
10
[20]
G
(17)
11
[21]
H
(18)
12
[22]
I
(19)
13
[23]
J
(20)
14
[24]
K
(21)
15
[25]
L
(22)
16
[26]
M
(23)
17
[27]

3
011
[30]
N
(24)
18
[30]
O
(25)
19
[31]
P
(26)
1A
[32]
Q
(27)
1B
[33]
R
(28)
1C
[34]
S
(29)
1D
[35]
T
(30)
1E
[36]
U
(31)
1F
[37]

4
100
[40]
V
(32)
20
[40]
W
(33)
21
[41]
X
(34)
22
[42]
Y
(35)
23
[43]
Z
(36)
24
[44]
.
(37)
25
[45]
$
(38)
26
[46]
%
(39)
27
[47]
(Information on printing color tables on color printers can be found here.)

In this table, the code or symbol name is shown on the first line, followed by the decimal value for that code or symbol, followed by the hexadecimal value and then the octal value. The binary, hexdecimal and octal value can also be computed based on the row and column where the code or symbol resides, or directly from the hexadecimal value. For example, the character "B" has the binary value "001 100", with "001" taken from the row and "100" taken from the column. Similarly, the "W" letter has the binary value "100 001".

The background color for each code or symbol indicates the category that the code resides in. Orange indicates basic punctuation and symbols. Yellow indicates numeric digits. Green indicates the uppercase letters.


Related Topics

American Standard Code for Information Interchange Reference (ASCII) (HTML)

SIXBIT Character Code Reference (HTML)

Extended Binary Coded Decimal Information Code Reference (EBCDIC) (HTML)

Baudot (5-Level) Character Code Reference (HTML)

Return to the Telecommunications Reference Index (HTML) 


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Mirroring of any material on this site in any form is expressly prohibited.
The official web site for this material is:  http://nemesis.lonestar.org
Contact this address for use clearances: clearance at nemesis.lonestar.org
Comments and queries to this address: web_reference at nemesis.lonestar.org]

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