DB9 male pins are as follows:
1 --------------- NC
2 ------------- - RX (Receive)
3 --------------- TX (transmitter)
4 --------------- NC
5 ----------------- GND
6 --------------- NC
7 ----- ------------ RTS (Output)
8 --------------- CTS (input)
9 ------- ---------- NC
Buy 2 pieces. power supply, for example. DC12V / 1.5A-R-Q