traffic light controller

[ratu semut]

i have a question here on how to design a traffic light controller. The controller should be be able to control a traffic light at 4-turn junction ( cross junction)

 

[crust]

A traffic light controller is just a finite state machine. The easiest way to do it is to draw the state diagram and then you can directly convert the state diagram to code for a micro or some vhdl.

For example, the start state is 1 light red, the other green, then go to yellow, then red, then pause, then the other goes green, etc.

 

[hotwaterwizard]

Something like this?

 

[hotwaterwizard]

Or like this?

 

[hotwaterwizard]

I have Lots more!

 

[plot]

:lol:

This has to be the most popular school project given to people to teach them how to do something of all time.

 

[hotwaterwizard]

I don't agree.
The Code Practice Oscillator is more popular beginners project.

 

[samcheetah]

how about a PIC based traffic light controller? has anyone built such a traffic light system?

hotwaterwizard can u explain the Code Practice Oscillator circuit????

 

[crust]

As for popular state machine type projects, the three that I see reappear each term are 1) traffic light controller, 2) eleveator controller, 3) soda machine.

 

[ratu semut]

i wanted to know the traffic light controller FSM state table. i have 8 current state, 4 inputs( RESET, C, TL, TS) , there are the next steps also, and 4 outputs.(each output has R Y G). R is red, Y is yellow, and G is green.
how can i do the K-maps from the outputs?
how about the state diagram?
how about the final ASM chart for the traffic light controller that has 8 current state?
please.....

 

[hotwaterwizard]

hotwaterwizard can u explain the Code Practice Oscillator circuit????

I started a new thread on this subject so The original Subject would remain here.
The new thread is located Here https://www.electro-tech-online.com/threads/float-recharging-what-does-it-mean.11316/

 

[zachtheterrible]

wile were on this subject, ive always wundered about this:

Is there a way to control trafic lights remotely? I see these little things on the top of the light that i think are sensors cuz they have a cover over the top to filter out sunlight im guessing, and i think that there are two sensors, one on top of the other. can ambulances n fire truks control them via IR?

 

[toolmantk]

Traffic light controller kit

Check this link for a kit to build a traffic light controller.

https://www.plans-kits.com/kits/index.html

 

[aires]

hotwaterwizard . . .

i tried sim ur ckt in an elec. workbench . . .it doesnt seem to work

i tried it all . . . it doesnt to work though

i'am trying to build a traffic light controller too . . .

like teh concept of ur design .. . .

and can you explain wat is d function of the DECADE COUNTER

in the ckt? THX !!!

 

[hotwaterwizard]

Here is the original link.
https://www.redcircuits.com/Page72.htm

 

[jrz126]

wile were on this subject, ive always wundered about this:

Is there a way to control trafic lights remotely? I see these little things on the top of the light that i think are sensors cuz they have a cover over the top to filter out sunlight im guessing, and i think that there are two sensors, one on top of the other. can ambulances n fire truks control them via IR?

Here in Erie, we have a system like this. There is actually a white light that will flash when it is used to switch the lights so that the drivers know to get the heck out of the way. It's controlled by radio too, there's little antennas sticking out of them
I think IR would be too dificult to use b/c you would have to line up the transmitter and reciever.
I cant remember the name of it, but I was told that some guy here in town invented it? I dunno if it's used everywhere though.

As for popular state machine type projects, the three that I see reappear each term are 1) traffic light controller, 2) eleveator controller, 3) soda machine.

I had to do #'s 1 and 3 last year. I wish I woulda known about this message board back then.

 

[skeeterb]

Traffic Light

Is this a single LED or multiple LED setup? If it is a single LED setup what would it take to make it a multiple LED setup?. What I mean is, is each direction a single LED or multiple LED.

 

[Rawle Alexander]

traffic light design

hey all;
I need some assistance in designing a 4way traffic light system and ped crossing using a pic16f877. I have already developed the codes for the 4 way lights but i am having trouble with incorporating the ped crossing. Could someone give me some assistance please.
Rawle.

ps. here is what i have.
View attachment Traffic light program.txt

 

[mneary]

Is there a way to control trafic lights remotely?

Everywhere in the USA that I've been they have those sensors. Emergency vehicles have strobes that flash in a particular pattern, and activate the appropriate signal state. Sometimes it's red in all directions, sometimes the emergency vehicle gets a green.

Some systems have to be enabled by a radio signal to prevent the kids from making their own strobes and playing with the signals.

 

[EasyGoat]

Thanks all! Especially HotWaterWizard for schematics.