Design And Construction Of Automatic Quiz Buzzer System

ABSTRACT

Here we propose a design of Quiz Buzzer Module by using AT89C51 microcontroller for 6 players. Earlier when the question is thrown upon the players two or more players hit the buzzer at the same time and it is so difficult to identify which team has pressed the buzzer first .This increases manual work and require lots of time. So to overcome such problems we have proposed a design of quiz buzzer module using AT89C51 microcontroller which will display the name of the team who has pressed the buzzer first and it will also display the time

TABLE OF CONTENTS

 TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWELDGEMENT

ABSTRACT

TABLE OF CONTENT

CHAPTER ONE

• INTRODUCTION
• BACKGROUND OF THE PROJECT
• AIM AND OBJECTIVE
• JUSTIFICATION OF THE STUDY
• SCOPE OF THE STUDY
• CONTRIBUTION TO KNOWLEDGE
• APPLICATIONS OF QUIZ BUZZER CIRCUIT
• LIMITATIONS OF THE STUDY

CHAPTER TWO

LITERATURE REVIEW

2.0      LITERATURE REVIEW

2.1      HISTORY OF 8 CHANNEL QUIZ BUZZER CIRCUIT

2.2     DESCRIPTION OF THE STUDY

2.3      SOFTWARE USED

2.4       HARDWARE

2.5      OPERATION

2.6      COMPARISON WITH HUMAN PLAYERS

2.7      DEVELOPMENT OF THE SYSTEM

CHAPTER THREE

3.0      METHODOLOGY

3.1      DATA ANALYSIS AND DISCUSSION

3.2      HARDWARE DESIGN

CHAPTER FOUR

4.0       TESTING AND IMPLEMENTATION

4.1      COMPONENT TESTING

4.2     PROJECT LIMITATIONS

4.3      PROBLEM FACED

4.4     CIRCUIT DESCRIPTION

4.5     BLOCK DIAGRAM
4.6    QUIZ BUZZER WORKING MODEL AND DESIGN

CHAPTER FIVE

5.0    CONCLUSION AND RECOMMENDATION

• CONCLUSIONS
• RECOMMENDATION

REFERENCES

CHAPTER ONE

1.0      INTRODUCTION

1.1      BACKGROUND OF THE STUDY

Quiz buzzers are used often at places like educational institutions where it is required for game shows and also in live quiz competitions broadcasted via television. A quiz buzzer allows any user to press the switch quickly in response to a question posed during competitions that are conducted in schools and colleges. The pressed switch gives a buzzing sound or alarm for some duration of time and the reaction time is very small. Buzzer can also be used in different applications such as annunciator panels; electronic metronome microwave oven and other house hold application.

Conventional systems require human intervention to decide which team has pressed the button and this system can be erroneous and even biased. Another problem arises when two members pressed the button at a negligible interval and it is difficult to guess who has pressed the buzzer first. Here we designed an automatic quiz buzzer system such that when more than one team presses the buzzer, the delay is accurately taken into account and number is displayed. We build the circuit using a microcontroller which scans the input from push buttons and displays the corresponding number on a display device. It is a simple circuit with minimum number of components and sans any complexities. The microcontroller takes into account the time delay between two buttons and the accurate number is displayed. Even though this system is only for 8 teams, more teams can be added by using another set of 8 push buttons.

1.2      AIM AND OBJECTIVE

The aim of this project is to designed and construction of automatic quiz buzzer system such that when more than one team presses the buzzer, the delay is accurately taken into account and number is displayed.

1.3      JUSTIFICATION OF THE STUDY

The circuit is a simple embedded system with a set of 8 push buttons being the input devices, a microcontroller as the controller and the output devices being a buzzer and a display. The whole operation is carried out by a microcontroller through a program written in C language and dumped inside the microcontroller. When one of the buttons is pressed, the buzzer starts ringing and the corresponding number is displayed on the liquid crystal display.

A quiz buzzer circuit can be implemented in several ways with the use of various controllers. These controllers include 555 timer and microcontrollers. The 555 timer based buzzer circuit is a simple and low-cost device wherein the time duration is determined by the resistor and capacitor value (RC constant). A microcontroller based buzzer circuit is a programmable timer wherein the time duration can be varied by changing the program code of the microcontroller.

1.4         SCOPE OF THE STUDY

The whole design process involves six steps. First step requires designing the circuit; the second step is drawing the circuit on any software like Proteus. The third step involves writing the code using high level language or assembly language and then compiling it on a software platform like Kielu Vision. The fourth step is dumping the code in microcontroller and fifth step is simulating the circuit.

The circuit involves using five major components – a Microcontroller, 8 SPST push buttons, a buzzer and liquid crystal display. The microcontroller used in this case is AT89C51, an 8 bit microcontroller manufactured by Atmel.

Reset Circuit Design

The reset resistor is selected such that the voltage at the reset pin, across this resistor is at minimum of 1.2V and the width of the pulse applied to this pin is greater than 100ms. Here we select a resistor of 100K ohms and a capacitor of 10uF.

Oscillator Circuit Design

The oscillator circuit is designed using a crystal oscillator of 12 MHz and two ceramic capacitors each 15pF. The crystal is connected between pins 18 and 19 of the microcontroller

Microcontroller Interfacing Design

The set of 8 push buttons are interfaced to port P1 of the microcontroller and a buzzer is interfaced to the port pin P0.0. The liquid crystal display is interfaced to the microcontroller such that all the input pins are connected to port P2.

Microcontroller Code

The code can be written using C language or assembly language. Here we select to write the program in C language using Kielu Vision. This is accomplished by the following steps

1. Create a new project on Kiel window and select the target.
2. Create a new file under the project and write the code.
3. Save the code with .c extension and add the file to the source group folder under the target folder.
4. Configure flash tools and create the hex file.
5. Compile the code by pressing F7.

Once the code is compiled and a hex file is created, next step is to dump the code into the microcontroller. Since here we are not using any hardware device, we simply use Proteus to dump the code. This is done by first drawing the circuit on Proteus and then adding the code to the microcontroller by right clicking on the device.

1.5       CONTRIBUTION TO KNOWLEDGE

Once the circuit is powered, the compiler will initialize the stack pointer and the variables having the non-zero initial values and perform other initialization process and then calls the main function. It then checks if any of the buttons is pressed. In other words the microcontroller scans for any of its input pins at port P1 to be zero or at logic low level. In case pressed, the display function is called by passing the corresponding number. The microcontroller then sends the relevant signals to the port connected to the liquid crystal display. The BCD to liquid crystal decoding operation is not required in this case as direct values are send to the port pins or the input pins of the liquid crystal display such that the corresponding LEDs start glowing and the number is displayed. Simultaneously, a high logic signal is also sent to the buzzer pin such that current flows through the device and the buzzer start ringing.

1.6       APPLICATIONS OF QUIZ BUZZER CIRCUIT

1. This device can be used at quiz competitions organized at schools, colleges and other institutions.
2. It can be also used for other games.
3. It can be used as at public places like banks, restaurants as a digital token display system.

1.6      LIMITATIONS OF THE STUDY

1. The microcontroller used is a CMOS device and is highly static and hence cannot be touched by bare hands.
2. It is a low range circuit, i.e. it is not possible to operate the circuit remotely.
3. It is a battery operated circuit and can easily run out of power once the battery life time ends.
4. It is a theoretical circuit and in practical application may require some passive components and even designing a linear power supply circuit to power the circuit directly using the mains supply

CHAPTER FIVE

CONCLUSION AND RECOMMENDATION

5.0      CONCLUSIONS

Quiz buzzers are used often at places like educational institutions where it is required for game shows. Conventional systems require human intervention to decide which team has pressed the button and this system can be erroneous and even biased. Another problem arises when two members pressed the button at a negligible interval and it is difficult to guess who has pressed the buzzer first. Here we designed an automatic quiz buzzer system such that when more than one team presses the buzzer, the delay is accurately taken into account and number is displayed. We build the circuit using a microcontroller which scans the input from push buttons and displays the corresponding number on a display device. It is a simple circuit with minimum number of components and sans any complexities. The microcontroller takes into account the time delay between two buttons and the accurate number is displayed. Even though this system is only for 8 teams, more teams can be added by using another set of 8 push buttons.

The design, specification and implementation of 8channel quiz buzzer circuit using microcontroller illustrate well the concept of the partition of control and data flow based on the virtual environment idea.

The basic idea of the software solution for a quiz buzzer circuit is to parse the string created by punch button and execute it if appropriate it sounds simple.

A Quiz buzzer circuit can be implemented in several ways with the use of various controllers. These controllers include 555 timers and microcontrollers. The 555 timer based buzzer circuit is a simple and low-cost device wherein the time duration is determined by the resistor and capacitor values (RC constant). A Microcontroller based buzzer circuit is a programmable timer wherein the time duration can be varied by changing the program code of the microcontroller. The following description of both these circuits will help you to compare both the circuits and their operations.

A timer can be operated in three modes such as monostable, astable and bistable for multivibrator circuits. The timer is used for generating pulses using pulse modulation technique. In a monostable mode, the output is set to high for a certain time period determined by the RC time constant when the timer is triggered at pin

2. In a bistable mode, the triggering input is connected at pin 2. When the triggered input is low, the output of the circuit will be in high state.

The reset button is connected at pin 4, and if the input is low, then the output is also in a low state.

Once the circuit is powered, the compiler will initialize the stack pointer and the variables having the non-zero initial values and perform other initialization process and then calls the main function. It then checks if any of the buttons is pressed. In other words the microcontroller scans for any of its input pins at port P1 to be zero or at logic low level. In case pressed, the display function is called by passing the corresponding number. The microcontroller then sends the relevant signals to the port connected to the Liquid Crystal Display (LCD).

The BCD to Liquid Crystal Display (LCD) decoding operation is not required in this case as direct values are send to the port pins or the input pins of the liquid crystal display such that the corresponding LEDs start glowing and the number is displayed. Simultaneously, a high logic signal is also sent to the buzzer pin such that current flows through the device and the buzzer start ringing.

The state machine required by any software is a result of analysis and design. Before we start to specify a state machine we must work out a clear picture of the task that the state machine is to take over. The aim of introduction of the state machine in software is not to eliminate all “if then else” statements. No, the state machine is required to take over the sequential (state dependent) part of the software control. For instance, the state machine should not be involved into checking whether the First contestant press the button and the buzzer make an alarm. If you start to define a state machine on that level you will get a monster that may be as difficult to understand as chaotic software with flags. In the design phase you have to identify the essential control problem that is to be realized by the state machine. The design is the most difficult and responsible part of the project. A design determines the quality of the software, in that case the quality of the control flow. The use of state machines in the software does not automatically guarantees a better result.

5.1      RECOMMENDATION

In view of the performance and quality of quiz buzzer, state government and federal government should be readily available to provide necessary assistance for quiz buzzer research work as this will strengthen and encourage young engineers to build on the past knowledge. Secondly, an institute for electronic work should be established with a standard laboratories or workshops for research purpose in the polytechnic for the proper use of under graduate student and to enhance productivity at large in technological advancement.

An automatic quiz buzzer system such that when more than one team presses the buzzer, the delay is accurately taken into account and number is displayed. We build the circuit using a microcontroller which scans the input from push buttons and displays the corresponding number on a display device.