pic16f84 programming

iam doing an embedded systems project using the pic16f84 picocontroller. its purpose is to measure times of two cars in drag race with the assistance of infra red sensors. the whole thing starts of with a sequence of traffic lights(l.e.d.s.) that change from red, amber and then to green. a delay of 1 sec is assumed. when the grren light goes on the timers for both cars start the timing and at the end of the racing distance are infra red sensors for each car. the lanes are separated to allow for the infra red to allow each car to have its own infra red beam ti trip. when disturbed they will make the particular clock to stop. i need help on the circuit design and the programming of the pic16f84.