Symbols can be looked up in "The Comprehensive LaTeX Symbol List":

UTF-8 as input encoding
If UTF-8 is used as input encoding, then the symbols can be defined using packages ascii for the symbols and newunicodechar for an easier interface of \DeclareUnicodeCharacter:
\documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage{ascii}
\usepackage{newunicodechar}
\newunicodechar{☺}{\SOH}
\newunicodechar{☻}{\STX}
\newunicodechar{♥}{\ETX}
\newunicodechar{♣}{\ENQ}
\newunicodechar{♠}{\ACK}
\newunicodechar{•}{\BEL}
\newunicodechar{○}{\HT}
\begin{document}
☺☻♥♣♠•○
\end{document}

Remarks:
The symbol • is already defined with \textbullet. Therefore \newunicodechar generates a warning, when replacing it with \BEL:
Package newunicodechar Warning: Redefining Unicode character on input line 11.
8-bit encodings
Some of the control character slots are covered by package inputenc. Others cannot be used, because line ends control characters are needed for line ends, for example.
However, if an 8-bit encoding is used with package inputenc, then usually the control characters are not assigned. With package ascii for the symbols it can be done the following way. To avoid trouble with copy and paste from the web page, I have used the ASCII replacement notation with ^^ after \begin{document}:
\documentclass{article}
\usepackage{ascii}
\usepackage[ansinew]{inputenc}
% \NUL
\DeclareInputText{1}{\SOH}% ^^A
\DeclareInputText{2}{\STX}% ^^B
\DeclareInputText{3}{\ETX}% ^^C
\DeclareInputText{4}{\EOT}% ^^D
\DeclareInputText{5}{\ENQ}% ^^E
\DeclareInputText{6}{\ACK}% ^^F
\DeclareInputText{7}{\BEL}% ^^G
\DeclareInputText{8}{\BS}% ^^H
% \HT
% \LF
\DeclareInputText{11}{\VT}% ^^K
% \FF
% \CR
\DeclareInputText{14}{\SO}% ^^N
\DeclareInputText{15}{\SI}% ^^O
\DeclareInputText{16}{\DLE}% ^^P
\DeclareInputText{17}{\DCa}% ^^Q
\DeclareInputText{18}{\DCb}% ^^R
\DeclareInputText{19}{\DCc}% ^^S
\DeclareInputText{20}{\DCd}% ^^T
\DeclareInputText{21}{\NAK}% ^^U
\DeclareInputText{22}{\SYN}% ^^V
\DeclareInputText{23}{\ETB}% ^^W
\DeclareInputText{24}{\CAN}% ^^X
\DeclareInputText{25}{\EM}% ^^Y
\DeclareInputText{26}{\SUB}% ^^Z
\DeclareInputText{27}{\ESC}% ^^[
\DeclareInputText{28}{\FS}% ^^ \DeclareInputText{29}{\GS}% ^^]
\DeclareInputText{30}{\RS}% ^^^ or ^^1e
\DeclareInputText{31}{\US}% ^^_
\DeclareInputText{127}{\DEL}% ^^?
\begin{document}
\noindent
\NUL^^A^^B^^C^^D^^E^^F^^G\\
^^H\HT\LF^^K\FF\CR^^N^^O\\
^^P^^Q^^R^^S^^T^^U^^V^^W\\
^^X^^Y^^Z^^[^^\^^]^^1e^^_\\
^^?
\end{document}
