OK here goes
25 Pin Plug 9 Pin
2 Transmit Data 3 TX
3 Receive Data 2 RX
4 Reqest to send 7 RTS
5 Clear to send 8 CTS
6 Data set ready 6 DSR
7 Signal Ground 5 SG
8 Carrier Detect 1 CD
20 Data Terminal ready 4 DTR
22 Ring Indicator 9 RI
Wire up the plug male or female as required as described and you are away being careful as its easy to connect to the wrong pin.
Or go to your local electronics/ computer shop and buy ready made.
Good luck
