I am trying to write a program which will listen to the serial input from Arduino board connected via usb, and sending output to serial port (COM4). But I don't know how to get input from serial port in Delphi. I need program to listen to the port, and whenever the input comes, it should react to it. Any suggestions?
http://sourceforge.net/projects/tpapro/ is a freeware tool we've used with great success for many years.