       9-pin    25-pin        PC       Angeschl. Geraet
------------------------------------------------------------
TX      3        2            ------>  
RX      2        3            <------
RTS     7        4            ------>
CTS     8        5            <------
DSR     6        6            <------
DCD     1        8            <------
DTR     4       20            ------>
RI      9       22            <------

Gnd     5        7


Ansichten von VORNE auf Stecker/Buchse:
                
9-PIN    

       1 2 3 4 5      MALE
       5 4 3 2 1      FEMALE
    ---------------      
   |   o o o o o   |     
    |             |       
     |  o o o o  |         
      -----------
        9 8 7 6       FEMALE 
        6 7 8 9       MALE
                
25-PIN  

       01  02  03  xx  13         MALE
       13  12  11  xx  01         FEMALE
    -----------------------                
   |   o   o   o   o   o   |          
    |                     |                 
     |   o   o   o   o   |                 
      -------------------                         
         25  24  xx  14           FEMALE
         14  15  xx  25           MALE

Spannungen:

TRUE  = Logical 1= Spannung -
FALSE = Logical 0= Spannung +
                            









   9-pin         25-pin              25-pin   9-pin         Description
   ----------------------------------------------------------------------
   pin 5         pin 7    <------>   pin 7    pin 5         Ground-Ground
   pin 3         pin 2    <------>   pin 3    pin 2         Xmit-Rcv
   pin 7         pin 4    <------>   pin 5    pin 8         RTS-CTS
   pin 1 and 6   pin 6    <------>   pin 20   pin 4         DSR-DTR 
   pin 2         pin 3    <------>   pin 2    pin 3         Xmit-Rcv
   pin 8         pin 5    <------>   pin 4    pin 7         CTS-RTS
   pin 4         pin 20   <------>   pin 6    pin 1 and 6   DTR-DSR 
