Para poder acceder a una tabla ASCII:
man ascii

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ASCII(7) Linux Programmer's Manual ASCII(7)

NAME
ascii – ASCII character set encoded in octal, decimal, and hexadecimal

DESCRIPTION
ASCII is the American Standard Code for Information Interchange. It is
a 7-bit code. Many 8-bit codes (such as ISO 8859-1, the Linux default
character set) contain ASCII as their lower half. The international
counterpart of ASCII is known as ISO 646.

The following table contains the 128 ASCII characters.

C program ‘\X’ escapes are noted.

Oct Dec Hex Char Oct Dec Hex Char
────────────────────────────────────────────────────────────────────────
000 0 00 NUL » 100 64 40 @
001 1 01 SOH (start of heading) 101 65 41 A
002 2 02 STX (start of text) 102 66 42 B
003 3 03 ETX (end of text) 103 67 43 C
004 4 04 EOT (end of transmission) 104 68 44 D
005 5 05 ENQ (enquiry) 105 69 45 E
006 6 06 ACK (acknowledge) 106 70 46 F
007 7 07 BEL ‘\a’ (bell) 107 71 47 G
010 8 08 BS ‘\b’ (backspace) 110 72 48 H

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