DB25 - DB25 Nullmodem cable
DB25  2 (TD) ___________ (RD) 3

 3 (RD) ___________ (TD) 2

20 (DTR) _________ (DSR) 6
               \___ (CD) 8

 7 (GND) _________ (GND) 7

 6 (DSR) _________ (DTR) 20
 8 (CD) ___/

 4 (RTS) _________ (CTS) 5

 5 (CTS) _________ (RTS) 4		 DB25
DSR and CD are tied together to let software think it's online

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