Downloaded 2,617 times
Uploaded bySubash Sambath Kumar
TRAFFIC LIGHT CONTROL SYSTEM USING 8085 MICROPROCESSOR
The document describes a traffic light control system using an 8085 microprocessor. It discusses the need for a traffic light system, describes the basic components including colors and signals. It then covers the hardware details of the 8085-based system and interface board, including ICs used. Algorithms and state diagrams are presented to show the logic for controlling lights and pedestrians.
More Related Content
Similar to TRAFFIC LIGHT CONTROL SYSTEM USING 8085 MICROPROCESSOR
TRAFFIC LIGHT CONTROL SYSTEM USING 8085 MICROPROCESSOR
- 1. Batch 5 MICRO PROCESSORASSIGN. PRESENTATION. - 2
- 2. OUR TOPIC IS: TRAFFICLIGHT CONTROL SYSTEM
- 3.
- 4. NEED FOR THESYSTEM : Traffic lightsstoplights/ traffic lamps/ traffic signals/ signal lights/ robots/ semaphore signaling devices positioned at road intersections, pedestrian crossings and other locations to control competing flows of traffic. Preventing accidents Improving safety Minimize travel time
- 5. ABOUT THE COLORSOF TRAFFIC LIGHT CONTROL Traffic lights alternate the right of way of road users by displaying lights of a standard color (red, yellow/amber, and green) By using a universal color code (and a precise sequence to enable comprehension by those who are color blind
- 6.
- 7.
- 8.
- 9. WHY 8085? Sufficient memoryfor the given scenario Basic units to be interfaced are supported by 8085 Less complicated in the aspect of coding Supports the necessary instruction sets Simple and robust
- 10. BASIC BLOCK DIAGRAM TIMER 5vPower Supply 8085 Microprocessor LED Display OUTPUT SIGNAL INPUT 7 Segment Display DISPLAYS WAITING
- 11.
- 12.
- 16. STATE DIAGRAM FORTRAFFIC CONTROLER
- 17.
- 18. HARWARE DETAILS: 2 PARTS •8085 Processor based system • Traffic Light Controller Interface board
- 19. IC’S USED: 8085 Microprocessor 8255 PPI 8253 Timer 8279 Keyboard and Display Interface
- 20.
- 21.
- 22.
- 23. 8255 FOR TRAFFICLIGHT : MVI A, 80H : OUT 83H (CR) : START: MVI A, 09H OUT 80H (PA) : MVI A, E4H OUT 81H (PB) : Initialize 8255, port A and port B in output mode Send data on PA to glow R1 and R2 MVI A, 0CH OUT 82H (PB) : Send data on PB to glow G3 ,G4,G3R,G4R Send data on PC to glow G3 R ,G4L
- 24. MVI C, 28H: Load multiplier count for delay CALL DELAY : Call delay subroutine MVI A, 09H OUT 80H (PA) : R2 MVI A, 24H OUT 81H (PB) : G4 MVI A, 00H OUT 82H (PB) : ,G4L & MVI C, 28H : Send data on PA to glow R1 and Send data on PB to glow G3 and Send data on PC to disable G3 L Enable Pedestrian Crossing Load multiplier count for delay
- 25. MVI A, 12H OUT(81H) PA : OUT (81H) PB : Y3 and MVI C, 0AH : CALL DELAY : MVI A, E4H OUT (80H) PA : MVI A, 09H OUT (81H) PB : R3 and MVI C, 28H : MVI A, 03H OUT 82H (PB) : L ,G2L CALL DELAY : Send data on Port A to glow Y1 and Y2 Send data on port B to glow Y4 Load multiplier count for delay Call delay subroutine Send data on port A to glow G1 and G2,G1R,G2R Send data on port B to glow R4 Load multiplier count for delay Send data on PC to glow G1 Call delay subroutine
- 26. MVI A, E4H OUT(80H) PA : Send data on port A to glow G1 and G2 MVI A, 09H OUT (81H) PB : Send data on port B to glow R3 and R4 MVI A, 00H OUT 82H (PB) : Send data on PC to disable G1 L ,G2L Enable Pedestrian Crossing MVI C, 28H : Load multiplier count (40i?) for delay CALL DELAY : Call delay subroutine MVI A, 12H OUT PA : Send data on port A to glow Y1 and Y2 OUT PB : Send data on port B to glow Y3 and Y4 MVI C, 0AH : Load multiplier count (10i?) for delay
- 27. DELAY SUBROUTINE: DELAY: DCR C: Decrement counter JNZ DELAY RET : Return to main program
- 28. LOGIC FOR PEDESTRIANSCROSSING
- 29.
- 30. 7 SEGMENT DISPLAYFOR TRAFFIC LIGHT- WORKING : The processor initializes the look up table pointer. The look up table contains the format for the 7 segment display
- 31. SEGMENT CODES FORCOMMON CATHODE DISPLAY
- 32. LOOK UP TABLEFOR DIGITS 1-8:
- 33. The microprocessor sendsthe data to the latch From the latch, the data is sent to 8279 Display Interface It then stores the data in its 16 X 8 Internal RAM
- 34. WRITING TO RAM: Thereare 6 seven segment displays in 8085 kit I 4 displays address II 2 displays data Here we make use of last two displays to interpret the waiting time in each signal
- 35. Hence we requirea decoder to select among the two displays Since there are 6 displays, we require a 3X8 decoder(74138) The inputs to these pins will be s1,s2,s0 of 8279 Output of decoder xx0 Left display xx1 Right Display Output to the seven segment displays will be from A3-0 and B3-0
- 36. ANALOG TO DIGITALCONVERTOR This is required because 8085 will require only +5V power supply
- 37.
- 38. Batch members DINESH .S (11I309) MARIAJERIN .J (11I324) SARATHY .K (11I340) SRINIVASAN .R (11I347) SUBASH .S (11I348) MURALI KRISHNAN .P (12I469)
- 39.