Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Traffic light system

Status
Not open for further replies.

rway

New Member
I am planning to do a traffic light system for my final year project....

Can anybody help me out with some special features to be added on to the system?

I need also the schematic diagram for the whole system..... Tq!

Best regards!
 
You won't learn anything if we do it for you.

Your first decision is whether to use a microcontroller such as a PIC or to do it in hardware.

Once you decide that, post your ideas and we can give you guidance.

Len
 
555 Timers would be a very crude way to do it.

A more elgant way (assuming he chooses the hardware option) would be to use counters.

Len
 
One thing to consider is the timing of the green,yellow and red lights.
For example the green and red lights may be on the same length of time, while the yellow is only on for a short time. Another thing to consider is that when the East/West is red the North/South is green.
I once did a simple one with a 555 timer as a clock driving a 4017 counter
with some outputs or'd for the red and green and a single output going to the yellow.
If you are going to be realistic and have traffic sensors, then a uprocessor is probably the best way to go.
 
The LED traffic Light circuit controls 6 LEDs (red, yellow and green) for both north/south directions and east/west directions. The timing sequence is generated using a CMOS 4017 decade counter and a 555 timer. Counter outputs 1 through 4 are wire ORed using 4 diodes so that the (Red - North/South) and (Green - East/West) LEDs will be on during the first four counts. The fifth count (pin 10) illuminates (Yellow - East/West) and (Red - North/South). Counts 6 through 9 are also wire ORed using diodes to control (Red - East/West) and (Green - North/South). Count 10 (pin 11) controls (Red - East/West) and (Yellow - North/South). The time period for the red and green lamps will be 4 times longer than for the yellow and the complete cycle time can be adjusted with the 47K resistor. The eight 1N914 diodes could be subsituted with a dual 4 input OR gate (CD4072).

**broken link removed**
 
The light sequence goes from G--->R--->Y--->G, would it be better for it to go from G--->Y--->R--->G?

:D
 
Take note of the position notes in the schematic:

Red (north/south) is on the (e/w) side.
Red (east/west) is on the (n/s) side;

The LEDs will have to be positioned on the pole in the correct way.


*now that I'm looking at it, I'm confused... could someone else here check it? :D*
 
Arctic Fox said:
*now that I'm looking at it, I'm confused... could someone else here check it? :D*

No, your description is not what the circuit says. Red (north/south) is actually as stated on the north/south side.

Here it goes.

Code:
4017 Pins  Direction E/W    Direction N/S
========================================
    11               R              Y
9,6,5,1              R              G
    10               Y              R
7,4,2,3              G              R
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top