Manual buzzers used for quiz competitions in schools and colleges create a lot of confusion in identifying the first respondent. It determines the contestant who first presses the switch (S1 through S8) to answer a question and locks out the remaining three entries. Simultaneously, the buzzer and the corresponding led should be ‘on’ after a particular competitor has pressed the pushbutton. The quiz table can be used for more number of contestants.

                         The circuit uses 89C51 microcontroller, and a few passive components that are readily available in the market. The circuit can be divided into three sections: power supply, controller and LED display.

                         This project is based on assembly language programming. The software platform used in this project is Keil uVision3.