Serial Port Pin Outs - Brainboxes CC-618 Hardware Manual

PCI Photon 4 Port RS232

Serial Port Pin Outs.

The pinouts of the 9 & 25 pin Male D connectors are given below.
Figure 5-2. Serial Port RS232 Pin Outs.
9 Pin connector:
25 Pin connector:
9 Pin D Serial Port RS232 Cables.
To connect to the AT style RS232 Serial Port you will need a
cable terminating in a 9 way female D connector. It is sound
practice to use cables with screws fitted that will allow you to
fasten the cable securely to the PC card.
In general, you will need to make up a "cross over" cable to
correctly interface the PC to the RS232 port of another computer
or device. Traditionally, making up the cross over cable has been
considered a black art. However, provided you have the pin outs
RS232 Pinouts and Cabling
Chapter 4 Page 37