Traffic Lights Circuit Help

[MiZZi]

We were ask to build a 1 input - 3 output traffic light system (green, orange & red) using only Decoders, Encoders, Multiplexers, Comparators & Adders. The input for the traffic lights will be done manually.The traffic lights turn green at logic 0 and there are two outputs at logic 1. First, orange will be high for 5 seconds, then red will be high and orange will be low after that. I don't know how to such system using only these components so I thought of using a counter wherein at logic 1 green is high. Then at logic 1 the counter will be high. From 000 - 011, orange will be active high then at 100 red will be active high. I have two questions:

1.) How can I keep red active high until the first input will be change manually to logic 0 (active high = green)?

2.) Is there anyway to put up a traffic system with these components(Decoders, Encoders, Multiplexers, Comparators & Adders) while achieving what is expected? Thanks

 

[KrisBlueNZ]

This sounds like a homework question so I've moved it to the homework forum. If it isn't, let me know and I'll move it back.

Let me clarify what you want. Your circuit has one input, and three outputs - that drive the green, amber and red LEDs in a single traffic light. Is that right?

When the control input is low, the traffic light turns green. (Green LED turns ON, and red and amber turn OFF).

When the control input is high, the traffic light first changes to amber, then five seconds later, changes to red. Is that all correct?

 

[MiZZi]

This sounds like a homework question so I've moved it to the homework forum. If it isn't, let me know and I'll move it back.

Let me clarify what you want. Your circuit has one input, and three outputs - that drive the green, amber and red LEDs in a single traffic light. Is that right?

When the control input is low, the traffic light turns green. (Green LED turns ON, and red and amber turn OFF).

When the control input is high, the traffic light first changes to amber, then five seconds later, changes to red. Is that all correct?

Definitely! It is what I wanted.

 

[KrisBlueNZ]

OK, so you can actually do most of the control very simply. Can you define the control signal for the green LED in terms of the input signal?

And can you define the amber and red LED control signals in terms of the input signal, along with a timer?

It's pretty clear that a five second delay is needed. "Decoders, Encoders, Multiplexers, Comparators & Adders" can't provide a delay unless you have a clock source at a known frequency. So you're going to need some kind of frequency source.

Once you have a frequency source, can you design a circuit using those components that will create a five second delay when triggered by a particular edge on the control input?

 

[MiZZi]

OK, so you can actually do most of the control very simply. Can you define the control signal for the green LED in terms of the input signal?

And can you define the amber and red LED control signals in terms of the input signal, along with a timer?

It's pretty clear that a five second delay is needed. "Decoders, Encoders, Multiplexers, Comparators & Adders" can't provide a delay unless you have a clock source at a known frequency. So you're going to need some kind of frequency source.

Once you have a frequency source, can you design a circuit using those components that will create a five second delay when triggered by a particular edge on the control input?

Thanks for your response! But I guess, our teacher was just challenging and fooling around with us. He then told us that it would be hard for us to do such a thing if we won't add a flip flop so I made this circuit with a flip flop and here is what I did:

If you can suggest something about this, then feel free. Thanks!