Introduction - If you have any usage issues, please Google them yourself
This realization is mainly the realization of traffic lights to complete the 9 seconds countdown, with 18F452 MCU as the center,
Control traffic through the 1 digital tube and 8 signal lamps. The first is the north south direction of the green light, red light east-west direction
Light, digital tube countdown when the countdown reaches 0, the state changed to red light north-south direction, East and West
To the green light, and then repeat the process.