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Pedestrian Crossing

In this lab session we'll build a puffin crossing. Complete all of the following tasks.
  1. Basic traffic light
    Using the available components (or the Wokwi simulator) create a single traffic light for cars (green, yellow, red). Run this traffic light controller in an endless loop.
  2. Pedestrian crossing
    Add a button for a pedestrian to press. Implement a handler function that should be called when the button is pressed. Make the button handler interrupt the regular program execution by triggering an interrupt request. Modify your original traffic light such that, when the button was pressed, the red light will light up longer. In addition, add a green light for pedestrians.
  3. Dealing with visually impaired people
    Add a buzzer to the system that helps visually impaired people to cross the street safely.