PCI 3 Port RS232
RS232 Pinouts and Cabling
Chapter 4 Page 39
9 Pin D Serial Port To A Modem.
If you are connecting a MODEM to a 9 pin D Serial Port then
you will NOT need a cross over cable and a straight through cable
connected as the 9 to 25 pin adapter given in Figure 4-5.
9 Pin D Serial Port Loop Back Connector.
A loop back connector can be used to echo RS232 data
transmitted by a serial port back into its own RS232 receiver. In
this way, the function of the serial port can be tested.
For an AT style Serial Port use the a female 9 way connector
wired as in Figure 4-4.
Figure 4-4. 9 Pin D Serial Loop Back Connector.
9 PIN D CONNECTOR
25 PIN D CONNECTOR
5
3
2
7
6
4
8
1
SCHEMATIC REPRESENTATION
ACTUAL REPRESENTATION