Hi, I have a question about to use serial port replace IR-Blaster to control external device,example for cable Box. The function is as the same as Replay box to control satellite box to record program. But the RS-232 only has two pin, pin2 and pin3 for TX and RX, in this situation is it possiblely to do this function? May someone can give me an advice to resolve this problem. Thanks a lot. Vivian