Traffic Lights With D-Flip Flop Moore Model?

Thread Starter


Joined Mar 20, 2008
Hi all,

I will design 4-way traffic lights. In north-south way there are NS-Red, NS-Yellow,NS-Green lamps and in east-west way there are EW-Red, EW-Yellow and EW-Green lamps.

When green or yellow light is ON for a way, on the other way there will be red.

The sequence of lights is in that way: green-yellow-red-green-yellow-red-...

Time of each light:
Green light: 45 seconds
Yellow Light: 15 seconds
Red Light: 60 seconds.
Clock period that will be applied on each flip flop is 15 seconds.

Create state diagrams and state tables and execute the circuit with D-flip flops in Moore model?

Can anybody help me with this?

Thanks from now...

Thread Starter


Joined Mar 20, 2008
I know I should start with state diagram of the model but I got stuck. I tried a state table but I am not sure with it. I attached it to my message.



Joined Oct 2, 2009
Are there not eight possible states using three flip flops?

When I do this, I draw a state transition diagram before I create a table...


Joined Oct 18, 2012
no help for the circuit? I have to finish it until tomorrow
Why did you wait this long with nothing to show for it? If you don't understand, you should ask the question while you still have time to rectify it.

Anyway, you know you need to count at some point. Do you have to create the counters from D flip flops as well?

I'm afraid you haven't been entirely clear on the requirements.