powershell serial port processor

Hello! server 2008R2 has 4 serial ports. program that i need should listen on all ports and catch input data (strings) if match is found- other data should be send to one of this ports. for example, if "HELLO" comes from COM1: than "DF109" should be sent to COM4: when something is written to the port program should check for feedback "OK" or similar. powershell coding will be preferred thank you philip