help with reading from serial port

Question

I'm newbie in programming. Want to send series of pulses (square waves) to PC and use C# to count the incoming pulses and display it like a running counter (real time). Frequency of pulses: 1-10Hz

however i cant figure out how to do this. Should i connect the pulses to CTS of serial port? (instead of sending the pulses via TX pin), and how about the logic level of Serial port? my pulses is 5V (hi), and 0V (low). Do i need MAX 232?


how to keep reading (listening) to the port while the application does something else?


please help. i need enlightenment from expert here :)  some sample code will be much appreciated.