Traffic Light Controller

By:Candace Lee

AndNayeon Kim

Instructors: Rajesh Gupta, Choon Kim, Shirley Miranda, Bridget Benson, Arash ArafeeCluster 1: Adventures in Embedded Computer SystemsJuly 2008

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The world's very first traffic lights were invented by J 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

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Computerised traffic control box

There are a couple of types of controlling systems used for traffic lights today. They are fixed timed, dynamic, coordinated, and actuated controls.

Fixed time:

Now used mainly in heavily traffic places, like large cities

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Uses a timer that changes the lights at certain times, unaffected by traffic

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Dynamic:

Uses inductive loops, or sensors, that are buried in pavement

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Detects oncoming cars, causing to change the lights

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Coordinated

Long strips of continuous green lights so that lots of cars can go long distances at a time

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Only used on one-way streets with fairly constant levels of traffic

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Modified Lab #5, added LEDs

Used the capsense wizard to place a different command for each slider port touched

Placed wires connecting LEDs and the LCD to ports that were previously assigned using the PSoC Designer 5.0

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CapSense slider, which represents the street

CY3214-PSoCEval USB developer kit.

Three LEDs (Light Emitting Diodes) which represent the 3 traffic lights

Used an LCD screen to caption the different phases.

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1. Create a new project on chip level (device CY8C24894)2. Open the user module and click on the Misc Digital tab then

select LCD and place it in the design.3. Set the LCD port to Port_44. Open the user module again and add three LED functions.

Place them in the design. Place them under the following ports and pins.1.LED_1- Port_3, Pin_3_0 2.LED_2-Port_3, Pin_3_1 3.LED_3-Port_3, Pin_3_2

5. Open the user module again and click on CapSensor, CSD, and finally CSD with PRS16 as clock source and place it in the design.

6. Select “properties” on the right-mouse-pull-down-menu of CSD_1 module and change the following propertiesScanning Speed: FastResolution: 9Modulator Capacitor Pin: P0[5]Feedback Register Pin: P1[5]

7. Select the “CSD Wizard” on right-mouse-pull-down-menu of CSD_1 module. This located at the bottom.

8. Enter 2 on N Sensors and double click inside the slot to apply the new value.

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9. Enter 1 on N Slider slot and double click inside the sot to apply the new value.

10. Click and drag P3[7] and drag it on SW0.11. Click and drag P3[0] and drag in on SW1.12. Enter 8 on N Sliders of “Slider-0” and double click within the slot.13. Enter 100 on Resolution of “Slider-0” and double click within the

slot.14. Click and drag the following ports:

P5[7] into W0 P5[5] into W1P5[3] into W2 P5[1] into W3P5[0] into W4 P5[2] into W5P5[4] into W6 P5[6] into W7

15. Then open up the main. c and enter the c codes that are required16. Open the tools tab at the top of the page and click options,

followed by build and compiler and select ImageCraft.17. Compile and build the project.18. Connect a wire between P0[5] and P1[5].19. Finally test out the project.

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The capsense slider has different points that respond to the different places touched.

The first two points on the slider shows that there are no cars are at the intersection, which is displayed on the LCD screen. LED number one stays on representing that the light is red.

As you slide your finger down the slider, the LCD screen displays that cars are approaching and the LED will change to LED 3. This represents that the light has changed green.

As you slide your finger down further, the LCD screen will change again and display caution, meaning that cars must slow down. LED 2 will turn on. This represents that the light is turning yellow.

Finally the LCD displays that there are no more cars passing and the LED 1 turns back on.

The sensor works accordingly:

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In conclusion our traffic light sensor is a great way to speed up traffic and keep streets running smoothly.

Stay safe on the roads =)

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