Traffic light sytem
CONTENTS:
1. Introduction.
2. System design.
A) Timing circuits.
B) Sequential circuits.
c) Combinational circuits.
3. Bill of materials.
4. Hardware design.
5. References.
6. Appendices.
1. Introduction:
This report is about the traffic light system through use of the digital logic design. The objective of this assignment is as follows:
• To design and construct a prototype for digital logic circuit applications.
• To apply and integrate the digital logic circuit principles taught in EEN1036.
• To gain experience of hardware construction.
• To appreciate the importance of coordinated teamwork and project management.
• To appreciate the nature of systems design.
The requirements of our assignment are listed below: • resistors: 470 × 3, 22k, 100k • 555 timer IC, such as NE555
• capacitors: 0.1μF, 1μF 16V radial, 10μF 16V radial • 4017 counter IC
• diodes: 1N4148 × 6
• LEDs: red, amber (or yellow), green • on/off switch
• 1M preset, horizontal • battery clip for 9V PP3
• stripboard: 20 rows × 21 holes
• Transistors: 2n3904
This project operates red, yellow and green in the correct sequence for the traffic lights.There are six lights to operate. The Red, yellow, and Green lights in the North-South direction will be designated as R1, Y1, G1. Similarly, the lights in the East-West direction will be called R2, Y2, and G2.
2. System design:
The system design of this project consists of the timing circuits, sequential circuits and combinational circuits which are all explained below.
A) Timing circuits:
The time taken for the complete red - red & yellow - green – yellow sequence can be varied from about 7s to about 2½ minutes by adjusting the 1M preset. Some yellow LED’s emit light that is almost red so you may prefer to use a yellow LED. The 555 ICtimer stable circuit provides clock pulses for the 4017 counter which has ten outputs (Q0 to Q9). Each
1. Introduction.
2. System design.
A) Timing circuits.
B) Sequential circuits.
c) Combinational circuits.
3. Bill of materials.
4. Hardware design.
5. References.
6. Appendices.
1. Introduction:
This report is about the traffic light system through use of the digital logic design. The objective of this assignment is as follows:
• To design and construct a prototype for digital logic circuit applications.
• To apply and integrate the digital logic circuit principles taught in EEN1036.
• To gain experience of hardware construction.
• To appreciate the importance of coordinated teamwork and project management.
• To appreciate the nature of systems design.
The requirements of our assignment are listed below: • resistors: 470 × 3, 22k, 100k • 555 timer IC, such as NE555
• capacitors: 0.1μF, 1μF 16V radial, 10μF 16V radial • 4017 counter IC
• diodes: 1N4148 × 6
• LEDs: red, amber (or yellow), green • on/off switch
• 1M preset, horizontal • battery clip for 9V PP3
• stripboard: 20 rows × 21 holes
• Transistors: 2n3904
This project operates red, yellow and green in the correct sequence for the traffic lights.There are six lights to operate. The Red, yellow, and Green lights in the North-South direction will be designated as R1, Y1, G1. Similarly, the lights in the East-West direction will be called R2, Y2, and G2.
2. System design:
The system design of this project consists of the timing circuits, sequential circuits and combinational circuits which are all explained below.
A) Timing circuits:
The time taken for the complete red - red & yellow - green – yellow sequence can be varied from about 7s to about 2½ minutes by adjusting the 1M preset. Some yellow LED’s emit light that is almost red so you may prefer to use a yellow LED. The 555 ICtimer stable circuit provides clock pulses for the 4017 counter which has ten outputs (Q0 to Q9). Each
References: We followed instructions using Digital Fundamentals by Floyd, and websites like www.doctronics.co.uk, www.educypedia.be/electronics/digitallogic.htm. 6. Appendices: The data sheets for this project are on the next page.