Design of Traffic Light based on FPGA

Xiaomin Han

1, a

, Shuzhen Huang

, Xiaohong Wang

, Yuying Ma

Shandong Vocational and Technical University of Engineering, Jinan 250200, China

Keywords: VHDL; traffic light; FPGA.

Abstract: This paper uses Altera's 5CSEMA5F31C6N chip to realize the hardware circuit description of the traffic

light system controller through VHDL language. It is compiled, simulated and downloaded to the FPGA

device for programming in Altera's EDA software platform Quartusii environment. The control process of

the traffic light system.

1 INTRODUCTION

With the increase of vehicles, traffic travel has

become a concern of everyone. Good traffic light

design can alleviate traffic pressure and ensure good

traffic order. This paper uses FPGA-based DE1-

SOC development board to simulate the intersection

traffic light. In addition to the basic traffic function,

the system also has a countdown function, which

simulates the actual traffic intersection. Provide a

theoretical basis for the actual traffic intersection.

Advantages of adopting VHDL language: (1)

powerful and flexible design; (2) modular and easy

to install; (3) reliable and easy to modify.

2 TRAFFIC SIGNAL CONTROL

TASKS

The intersection traffic light designed in this paper

has the function of indicating the opening and

stopping. Red, green and yellow signal lights and

digital tube displays are installed at each entrance.

Traffic rules: When the east-west direction is

open, when the north-south direction is forbidden,

the green light in the east-west direction is bright for

39 seconds, then the yellow light is on for 4 seconds,

the red light is bright, and the south-south direction

is red for 43 seconds, and the green light is bright.

When the north-south direction is open, when the

east-west direction is prohibited, the green light in

the north-south direction is bright for 20 seconds,

then the yellow light is on for 4 seconds, the red

light is bright, the east-west direction is red light for

24 seconds, and the green light is bright. Loop in

turn.

There is a set of countdown monitors in both the

east and west directions to show the passage time

and the forbidden time.

3 OVERALL DESIGN

This design is based on FPGA to complete the traffic

light control system. The 5CSEMA5F31C6N is used

as the core controller of the control system. The

three design entities are used to implement the

traffic light design in VHDL language, including:

crossover design entity, traffic signal light and

digital tube display circuit design entity, top-level

design entity (Qing Zhang, Xiaoping Cao, 2017).

4 DESIGN OF VARIOUS PARTS

OF THE SYSTEM

4.1 Frequency Division Circuit Design

The frequency of the DE1-SOC development board

is 50MHZ. This design requires 1HZ frequency, so

the process design and if...else statement are used to

complete the crossover design (Rundong Bi, Bo Gao,

2016). The schematic diagram module is shown in

Fig.1:

306

Han, X., Huang, S., Wang, X. and Ma, Y.

Design of Trafﬁc Light based on FPGA.

DOI: 10.5220/0008386103060309

In Proceedings of 5th International Conference on Vehicle, Mechanical and Electrical Engineering (ICVMEE 2019), pages 306-309

ISBN: 978-989-758-412-1

Fig 1. Frequency division circuit module.

Fig 2. Control circuit module.

4.2 Traffic Signal and Digital Tube

Display Circuit Design - Control

Circuit

This design uses LEDs as signal lights. The lamp is

turned on and off by means of the

5CSEMA5F31C6N chip. The digital tube uses a

seven-segment digital tube with a common anode. A

total of four digital tubes are used, two of which are

used for the display of the countdown of the east and

west roads, and the other two are used for the

display of the countdown of the north and south

roads. Using state machine to complete the signal

light off and digital tube counting design, it can be

divided into 4 states, namely: east and west green

light, north and south red light (S1); east and west

yellow light, north and south red light (S2); east and

west red light, north and south Green light (S3); red

light, north and south yellow light (S4). Program

design idea: first design a 68-ary addition counter,

and then design the 39-digit, 4-ary, 20-digit

subtraction counter to achieve the display count of

the digital tube; at the same time, complete the

design of the signal light on and off in each state (Bo

Li, Mengdi Yang, Xinxin Wang, 2019). The

generated schematic module is shown in Fig2.

4.3 Top Design

The top-level entity is formed by the frequency

dividing circuit and the control circuit, and the top-

level schematic diagram is shown in Fig3 (Zheming

He, Shen Yuan, et al, 2019).

Fig 3. Top-level entity.

The partial simulation circuit diagram is shown in Fig4.

Fig 4. Partial simulation circuit.

Design of Trafﬁc Light based on FPGA

307

Fig 5. Device selection.

Fig 6. Pin binding.

5. PROGRAMMING TEST AND

RESULT ANALYSIS

5.1 Device Selection

Select the CycloneV Series 5CSEMA5F31C6N chip

is shown in Fig.5.

5.2 Pin Binding

Pin binding is shown in Fig.6.

5.3 Analysis of Results

After the circuit is connected, the written test

program is downloaded to the chip for testing. It is

ICVMEE 2019 - 5th International Conference on Vehicle, Mechanical and Electrical Engineering

308

observed that the display state of a small lamp and

the digital tube display meet the task requirements,

indicating that the design has no problem.

6 SUMMARY

The FPGA-based traffic light design proposed in this

paper has the advantages of easy implementation,

convenient modification and stability. Compared

with the traditional MCU-based traffic light control

system, this design has a broader development

prospect.

REFERENCES

Bo Li, Mengdi Yang, Xinxin Wang, Design of Traffic

Light Control System Based on EDA Technology.

Hebei Agricultural Machinery, 2019, (05), 41-42.

Qing Zhang, Xiaoping Cao, Design of Intelligent Traffic

Signal Controller Based on FPGA. Shandong

Industrial Technology. 2017, (16), 141.

Rundong Bi, Bo Gao,Design of Traffic Signal Control

System Based on FPGA. Chinese Journal of Electron

Devices.2016, 39 (01), 229-234.

Zheming He, Shen Yuan, et al. Design of Traffic Control

Light Based on FPGA. Computer Knowledge and

Technology.2019, 15(07), 239-239+257.

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