8 Channel Quiz Buzzer Circuit using Microcontroller

Project Title

8 Channel Quiz Buzzer Circuit using Microcontroller

Project Area of Specialization RoboticsProject Summary

In this project, the design and working of an 8 Channel Quiz Buzzer Circuit using Microcontroller (8051), which tells  which team has pressed the button first in a quiz or game show. 

Quiz buzzers are used often at places like educational institutions and game shows, where it is required for the organizers to know who pressed the button first. 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 in this project, an Automatic Quiz Buzzer System will be designed in which, when more than one team presses the buzzer, the delay between the two button presses is accurately taken into account and the corresponding number is displayed.

Project Objectives

This is accomplished by the following steps:

1. Create a new project on Keil window and select the target (microcontroller).
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. Compile the code and create the hex file.

Project Implementation Method

The circuit using 8051 microcontroller, which scans the input from push buttons and displays the corresponding number on a display device (7-Segment Display). It is a simple circuit with minimum number of components and sans any complexities. Even though this system is designed for only for 8 teams, more teams can be added by using another set of 8 push buttons.

Benefits of the Project

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

Technical Details of Final Deliverable

The circuit involves using five major components – 8051 Microcontroller, SPST Push Buttons, a buzzer and a common anode 7 segment display.  The microcontroller used in this case is AT89C51, an 8 bit microcontroller manufactured by Atmel (now Microchip).

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 100 ms.  Here we select a resistor of 10K? and a capacitor of 10?F.

Oscillator Circuit Design: The oscillator circuit is designed using a crystal oscillator of 11.0592 Mhz and two ceramic capacitors each 33pF. 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 P3.3. The 7 segment display is interfaced to the microcontroller such that all the input pins are connected to port P2. 

Final Deliverable of the Project Hardware SystemCore Industry ITOther Industries Media Core Technology OthersOther Technologies RoboticsSustainable Development Goals Quality Education, Peace and Justice Strong InstitutionsRequired Resources

Item Name	Type	No. of Units	Per Unit Cost (in Rs)	Total (in Rs)
			Total in (Rs)	48950
conference paper	Miscellaneous	1	5000	5000
Thesis	Miscellaneous	1	5000	5000
AT89C51 (8051 Microcontroller)	Equipment	5	190	950
7 Segment Display	Equipment	5	300	1500
Programmable Touch screen panels	Equipment	2	13900	27800
Resisters (10K?, 100K?,470K?)	Equipment	30	12	360
2N2222 NPN Transistors – 2	Equipment	4	400	1600
5V Buzzer	Equipment	2	700	1400
Capaciters (10?F,33pF)	Equipment	10	100	1000
8051 Programmer	Equipment	4	650	2600
11.0592 MHz Crystal	Equipment	4	40	160
5V Power Supply	Equipment	2	790	1580