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Traffic light controller


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A minor project report on Traffic Light Controller using 8051(AT89C51) micro controller.

A minor project report on Traffic Light Controller using 8051(AT89C51) micro controller.

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  • 1. A MINOR PROJECT ON TRAFFIC LIGHT CONTROLLER Based on AT89C51 Microcontroller Presented By: Ramkrishna Mishra (5910428)
  • 2. HISTORY OF TRAFFIC LIGHT were invented by J The world's very first traffic lights P Knight installed near London's House of Commons, which was on the intersection of George and Bridge Street, in 1868. In 1914 The American Traffic Signal Company installed red and green traffic lights on every corner of the intersection of 105th Street and Euclid Avenue in Cleveland, Ohio. First traffic lights were all controlled by either timing, or manually switched
  • 3. RED Come to complete stop at stop line or before crosswalk or intersection. After stopping, you may turn right on red at most intersections if the way is clear. Some school districts have local policies that prohibit right turns on red by bus operators. Some intersections display “NO TURN ON RED,” which you must obey.
  • 4. YELLOW Stop The if you can do so safely. light will soon be red. GREEN Go, If but only if intersection is clear. turning left, wait for gap in oncoming traffic to complete turn.
  • 5. Few things about AT89C51  It has four Ports: Port 0 Port 1 Port 2 Port 3 These Four ports works as Input port as well as output port.
  • 6. ABSTRACT The function of traffic lights is to provide sophisticated control and coordination to ensure that traffic moves as smoothly and safely as possible.
  • 7. FEATURES OF TRAFFIC LIGHT CONTROLLER controller assumes equal traffic density on all the roads. The free left turn condition is provided throughout the entire signal period. The control can also be exercised manual when desired.
  • 8. INTRODUCTION • This project uses a LED light as an indicator. • A microcontroller for auto change signal after a specific time interval. • The LEDs are automatically on and off by making the corresponding port pin of the micro controller high.
  • 9. COMPONEN TS AT89C51 Microcontroller Capacitor (30pF x2,10µF) Resistor (8.2KΩ) Crystal oscillator (11.0592MHz) LED light (Red, Green, Blue) PCB Power supply
  • 12. WORKIN G  The pins of the various input output ports of the microcontroller are connected directly to the given LEDs.  The 8051 is programmed in a manner that the respective LEDs glow by setting the required bit using assembly language and a certain amount of delay is provided depending on the user.
  • 13. PROGRAM #include<reg51.h> sbit RE = P0^0; sbit YE = P0^1; sbit GE = P0^2; sbit RW = P0^3; sbit YW = P0^4; sbit GW = P0^5; sbit RN = P0^6; sbit YN = P0^7; sbit GN = P2^0; sbit RS = P2^1; sbit YS = P2^2; sbit GS = P2^3; void Delay(void)
  • 14. { unsigned int j;//,i; ////for(i=0;i<200;i++) for(j=0;j<700;j++); } void SuperDelay() { unsigned int i; for (i=0;i<25;i++); Delay(); } void main() { while (1) { RE=0; GE=1; YE=0; RW=1; GW=0; YW=0; RN=1; GN=0; YN=0; RS=1; GS=0; YS=0; SuperDelay(); GE=0; YE=1; Delay(); RE=1; GE=0; YE=0; RW=0; GW=1; YW=0; RN=1; GN=0; YN=0; RS=1; GS=0; YS=0; SuperDelay(); GW=0; YW=1; Delay(); RE=1; GE=0; YE=0; RW=1; GW=0; YW=0; RN=0; GN=1; YN=0; RS=1; GS=0; YS=0; SuperDelay(); GN=0; YN=1; Delay(); RE=1; GE=0; YE=0; RW=1; GW=0; YW=0; RN=1; GN=0; YN=0; RS=0; GS=1; YS=0; SuperDelay(); GS=0; YS=1; Delay(); } }
  • 15. MOTIVATION The project finds high practical and widespread use. It is a very primitive application of the microcontroller. Easy and convenient to be built for a beginner as the coding comprises of basic instructions.
  • 16. SCOP E This project can be enhanced in such a way as to control automatically the signals depending on the traffic density on the roads using sensors like IR detector/receiver module extended with automatic turn off when no vehicles are running on any side of the road which helps in power consumption saving.