Two way Traffic Light. How to transition.

Discussion in 'The Projects Forum' started by nubpwn3r, Oct 15, 2015.

  1. nubpwn3r

    Thread Starter New Member

    Oct 15, 2015
    We were tasked to make a two way traffic light.
    Ive thought of hwo to make it.

    I will use two 15 seconds timer for the Green and Red display and use flip flop for a 3 second countdown for the yellow

    The only problem i have at the moment is how to switch/make the transition between the timers.

    Like: 15 seconds BCD counter for green, then adter the 15secsonds, id like to switch to the yellow 3 seconds countdown timer then to the Red.

    As of now, i just read about the decade counter IC 4017 it could be a good alternative for the BCD 15 seconds timer, but still, how do I make the transitions between timer? THANKS IN ADVANCE!!! :))
  2. djsfantasi

    AAC Fanatic!

    Apr 11, 2010
    Depending on if you are limited to exactly those times (e.g., can yellow be 5 seconds?), a 4017 will do the transitions for you. And you only need one counter.
  3. nubpwn3r

    Thread Starter New Member

    Oct 15, 2015

    I chose the yellow light to only be 3 seconds :)) cuz it would be too odd to see a yellow light on for 5 secs, but yea we are not restricted on that condition :))

    please correct me if im wrong, but 4017 is only 10 counter right?
    and by saying it will do transitions for me, you mean, by cascading them?

    Edit1: Im getting an idea already. Thx!!

    Edit2: 4017 counter have A - J individual outputs yes? Is it possible to connect all outputs A - J to only 1 LED? What I have in mind is to let the LED stay on for the set period of time
    Last edited: Oct 15, 2015