ASCII Characters
 The ASCII character set defines 128 characters (0 to 127 decimal, 
 0 to FF hexadecimal, and 0 to 177 octal). This character set is a 
 subset of many other character sets with 256 characters, including 
 the ANSI character set of MS Windows, the Roman-8 character set of 
 HP systems, and the IBM PC Extended Character Set of DOS, and the 
 ISO Latin-1 character set used by Web browsers. They are not the 
 same as the EBCDIC character set used on IBM mainframes.
 The Control Characters
 The first 32 values are non-printing control characters, such as 
 Return and Line feed. You generate these characters on the keyboard 
 by holding down the Control key while you strike another key. For 
 example, Bell is value 7, Control plus G, often shown in documents 
 as ^G. Notice that 7 is 64 less than the value of G (71); the 
 Control key subtracts 64 from the value of the keys that it modifies.
-----------------------------------------------------------------
      Oct Dec Hex Ctrl-key  Control Action
 NUL   0   0   0    ^@      Null character
 SOH   1   1   1    ^A	   Start of heading, = console interrupt
 STX   2   2   2    ^B	   Start of text, maintenance mode on HP console
 ETX   3   3   3    ^C	   End of text
 EOT   4   4   4    ^D	   End of transmission, not the same as ETB
 ENQ   5   5   5    ^E	   Enquiry, goes with ACK; old HP flow control
 ACK   6   6   6    ^F	   Acknowledge, clears ENQ logon hang
 BEL   7   7   7    ^G	   Bell, rings the bell		
  BS  10   8   8    ^H	   Backspace, works on HP terminals/computers
  HT  11   9   9    ^I	   Horizontal tab, move to next tab stop
  LF  12  10   a    ^J	   Line Feed
  VT  13  11   b    ^K	   Vertical tab
  FF  14  12   c    ^L	   Form Feed, page eject
  CR  15  13   d    ^M	   Carriage Return
  SO  16  14   e    ^N	   Shift Out, alternate character set
  SI  17  15   f    ^O	   Shift In, resume default character set
 DLE  20  16  10    ^P	   Data link escape
 DC1  21  17  11    ^Q	   XON, with XOFF to pause listings; "okay to send"	
 DC2  22  18  12    ^R	   Device control 2, block-mode flow control
 DC3  23  19  13    ^S	   XOFF, with XON is TERM=18 flow control
 DC4  24  20  14    ^T	   Device control 4
 NAK  25  21  15    ^U	   Negative acknowledge
 SYN  26  22  16    ^V	   Synchronous idle
 ETB  27  23  17    ^W	   End transmission block, not the same as EOT
 CAN  30  24  18    ^X	   Cancel line, MPE echoes !!!
  EM  31  25  19    ^Y	   End of medium, Control-Y interrupt
 SUB  32  26  1a    ^Z	   Substitute
 ESC  33  27  1b    ^[	   Escape, next character is not echoed
  FS  34  28  1c    ^\	   File separator
  GS  35  29  1d    ^]	   Group separator
  RS  36  30  1e    ^^	   Record separator, block-mode terminator
  US  37  31  1f    ^_ 	   Unit separator


 Printing Characters
 Char  Octal   Dec     Hex   Description
  SP   	 40  	32  	20   	Space
  !  	 41  	33  	21	Exclamation mark
  "      42     34      22      Quotation mark (" in HTML)
  #  	 43  	35  	23	Cross hatch (number sign)
  $  	 44  	36	24	Dollar sign
  %  	 45  	37	25	Percent sign
  &      46     38      26      Ampersand
  '  	 47  	39	27	Closing single quote (apostrophe)
  (  	 50  	40	28	Opening parentheses
  )  	 51  	41	29	Closing parentheses
  *  	 52  	42	2a	Asterisk (star, multiply)
  +  	 53  	43	2b	Plus
  ,  	 54  	44	2c	Comma
  -  	 55  	45	2d	Hypen, dash, minus
  .  	 56  	46	2e	Period
  /  	 57  	47	2f	Slant (forward slash, divide)
  0 	 60  	48	30	Zero		
  1  	 61  	49	31	One
  2  	 62  	50	32	Two
  3  	 63  	51	33	Three
  4  	 64  	52	34	Four
  5  	 65  	53	35	Five
  6  	 66  	54	36	Six
  7  	 67  	55	37	Seven
  8  	 70  	56	38	Eight
  9 	 71  	57	39	Nine
  :  	 72  	58	3a	Colon
  ;  	 73  	59	3b	Semicolon
  <      74     60      3c      Less than sign (&amp;lt; in HTML)
  =  	 75  	61	3d	Equals sign
  >      76     62      3e      Greater than sign (&amp;gt; in HTML)
  ?  	 77  	63	3f	Question mark
  @ 	100  	64	40	At-sign
  A 	101  	65	41	Uppercase A
  B 	102  	66	42	Uppercase B
  C 	103  	67	43	Uppercase C
  D 	104  	68	44	Uppercase D
  E 	105  	69	45	Uppercase E
  F 	106  	70	46	Uppercase F
  G 	107  	71	47	Uppercase G
  H 	110  	72	48	Uppercase H
  I 	111  	73	49	Uppercase I
  J 	112  	74	4a	Uppercase J
  K 	113  	75	4b	Uppercase K
  L 	114  	76	4c	Uppercase L
  M 	115  	77	4d	Uppercase M
  N 	116  	78	4e	Uppercase N
  O 	117  	79	4f	Uppercase O
  P 	120  	80	50	Uppercase P
  Q 	121  	81	51	Uppercase Q
  R	122  	82	52	Uppercase R
  S 	123  	83	53	Uppercase S
  T 	124  	84	54	Uppercase T
  U 	125  	85	55	Uppercase U
  V 	126  	86	56	Uppercase V
  W 	127  	87	57	Uppercase W
  X 	130  	88	58	Uppercase X
  Y 	131  	89	59	Uppercase Y
  Z 	132  	90	5a	Uppercase Z
  [ 	133  	91	5b	Opening square bracket
  \ 	134  	92	5c	Reverse slant (Backslash)
  ] 	135  	93	5d	Closing square bracket
  ^ 	136  	94	5e	Caret (Circumflex)
  _ 	137  	95	5f	Underscore
  ` 	140  	96	60	Opening single quote
  a 	141  	97	61	Lowercase a
  b 	142  	98	62	Lowercase b
  c 	143  	99	63	Lowercase c
  d 	144    100	64	Lowercase d
  e 	145    101	65	Lowercase e
  f 	146    102	66	Lowercase f
  g 	147    103	67	Lowercase g
  h 	150    104	68	Lowercase h
  i 	151    105	69	Lowercase i
  j 	152    106	6a	Lowercase j
  k 	153    107	6b	Lowercase k
  l 	154    108	6c	Lowercase l
  m 	155    109	6d	Lowercase m
  n 	156    110	6e	Lowercase n
  o 	157    111	6f	Lowercase o
  p 	160    112	70	Lowercase p
  q 	161    113	71	Lowercase q
  r 	162    114	72	Lowercase r
  s 	163    115	73	Lowercase s
  t 	164    116	74	Lowercase t
  u 	165    117	75 	Lowercase u
  v 	166    118	76	Lowercase v
  w 	167    119	77	Lowercase w
  x 	170    120	78	Lowercase x
  y 	171    121	79	Lowercase y
  z 	172    122	7a	Lowercase z
  { 	173    123	7b	Opening curly brace
  | 	174    124	7c	Vertical line
  } 	175    125	7d	Closing curly brace
  ~ 	176    126	7e	Tilde (approximate)
 DEL    177    127      7f      Delete (rubout), cross-hatch box