DC serial port:

back-side:

--------------------------------------------------------------
|                                                            |
|                                 video          serial      |
|                              |          |    |       |     |
|                                             B1       B10   |
|                                                            |
--------------------------------------------------------------
 

b1  +5V
b2
b3  GND
b4  RX2
b5  TX2
b6  RTS
b7  CTS
b8
b9
b10  +3,3V

(c) by bITmASTER