Hello,
First of all you need a special cable to connect the powerbase to the computer (on serial port) more information here : http://www.pclapcounter.be/scalextric_digital_new.html
About pitstop detection, there is many possibility but if you don't have knowledge in electronic (like me
) then the best is to ask a pitstop by pressing the LC or Brake button of your hand controler during 3 seconds, more information here : http://www.pclapcounter.be/fuel_management.html
So no need to add special hardware to detect pitstop