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Because of the varying lengths of the codes for the characters Morse code was unsuitable for machine encoding and decoding. There was a great intrest in replacing the human telegrap operators vith machines, and in the 1870's the Baudot code was invented by a Frenchman named Emilie Baudot.
The Baudot Code used the same number of signal elements (bits) to represent each character, and was far better suited to machine encoding and decoding.


The five-bit code could generate only 32 possible combinations, not enough to represent the 26 characters of the alphabet, the 10 decimal digits, etc. Therfore Baudot used two shift-control characters (1111 and 11011) to select one of the two character sets each composed of 26 and 28 characters.
Code  L   F
11001 A   -
10011 B   ?
01110 C   :
10010 D   Who are you?
10000 E   3
10110 F   Not allocated
01011 G   Not allocated
00101 H   Not allocated
01100 I   8
11010 J   Bell
11110 K   (
01001 L   )
00111 M   :
00110 N   ,
00011 O   9
01101 P   0
11101 Q   1
01010 R   4
10100 S   ,
11100 U   7
01111 V   =
11001 W   2
10111 X   /
10101 Y   6
10001 Z   +
00000 BLANK
11111 Letters(L) shift
11011 Figures(F) SHift
00100 SPACE
00010 Carrage Return
01000 Line Feed
The first question that pops to mind is 'Why aren't the codes sorted alphabetically?' Answer: Because it was originally designed to by typed by hand on a five finger keyboard (2 left 3 right) and printed/punched on ticker tape. Baudot keying was synchronized with a mechanical timer that alternately unlocked the keys and advanced the ticker tape on the receiving end about 8 to 10 times a second--advance,unlock,punch,lock,advance....

The codes were arranged so that the frequently-used letters required the least amount of keys pressed. Here is a Baudot table, arranged for operator keying:

5 4  L F  3 2 1     5 4  L F  3 2 1   
---------------     ---------------   
     A 1  *         *    - .  *       
     E 2    *       *    X 9/   *     
     Y 3      *     *    S 7/     *   
     / 1/ * *       *    Z :  * *     
     I 3/   * *     *    W ?    * *   
     U 4  *   *     *    T ^2 *   *   
     O 5  * * *     *    V ^1 * * *   
                                      
  *  J 6  *         * *  K (  *       
  *  G 7    *       * *  M )    *     
  *  B 8      *     * *  R -      *   
  *  H '  * *       * *  L =  * *     
  *  F 5/   * *     * *  N £    * *   
  *  C 9  *   *     * *  Q /  *   *   
  *  D 0  * * *     * *  P +  * * *   

Control Codes
5 4 3 2 1   
---------
  *       Space and Figures follow (F row)	 
*         Space and Letters follow (L row)
* *       Error, delete previous character
Keyboard mapping:
  1. Right ring finger
  2. Right middle finger
  3. Right index finger
  4. Left index finger
  5. Left middle finger
The 1/ 3/ 5/ 7/ 9/ were used to transmit fraction numerators for stock market quotes.

For example:

    M S F T   2 4 1/8   I B M   8 3 3/4 
--------------------------------------------
\ o o o   o           o     o   o           \
/   o   o   o       o     o o o o           /         
\         o     o o                   o     \
/   o   o     o   o     o   o       o       /
\     o o o     o   o   o o     o o o o     \  
--------------------------------------------
  1. Can you guess which symbol actually was written to ticker tape at one point?
  2. Did you notice the + symbol is all holes punched, and three in a row means 'tear off here'. There's something familiar about that ...

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