''STOPWATCH WITH LAP TIMES'' MINI PROJECT

In this mini project, we are going to make simple stopwatch by using microcontroller 89C52 tools kit and LCD display. A stopwatch allows you to record the exact number of hours, minutes, and seconds. It is a special type of watch with buttons that start, stop and then zero the hands, used to time races. 

Objectives:

1. To design and construct the Stopwatch with Lap Times using 8052 microcontroller (AT89C52).
2. To interface the Stopwatch with Lap times with C language into AT89C51

Description of the stopwatch with lap times

             In this project, a stopwatch timing functions are traditionally controlled by one push button and microcontroller 8052 forms the processing part which firstly receives data when the switch is pressed for the first time. The result obtained from the above operation is given though output port of 8052 to LCD display of relevant data.

              In this system, the timer will start running indicated the first lap when the push button is pressed. When the push button is pressed for the second time, the timer will stop the first lap and display at the LCD while second lap is start running continue from the first lap. For the third time, the second lap will stop and display the second lap time. 

Flowchart of software interfacing

Parts List:

• 16x2 LCD display
• 89C52 uc kit
• IC 89C52
• Toolstick850-b-sk
• Resistor 10k 
• Switch button
• Male pin connector strip 
• Strip board
• jumper dupont wires

Software and circuit functional block diagram 

i)  LCD display "FIQ MAL JAHID" & "STOPWATCH"
     
     
      -  Students name is appeared when the power supply is connected 


ii) LCD display LAP 1 and LAP 2
     
       

    -  When switch is pressed for the first time, the first lap is going to count up

     -  Switch button is pressed for the second time to indicate first lap and continue the second          lap

     -  For the 3rd time switch is pressed, Lap 1 and Lap 2 display in the LCD 



Analysis

Regarding to our mini project title Stopwatch with Lap Times, the experiment is successfully done and it running in good condition. Basically from the above title, we are making Stopwatch with Lap Times by implementing Proteus software to make its schematic diagram and Kiel uVision for its coding. Our device runs on 5V of supply, the device will start and LCD will display name and title of our groups.

Then, push button is pressed to run the first lap of the stopwatch. At the preliminary stage of developing this project. The LCD was a bit sensitive when the push button is pressed. After troubleshoot the coding, we found that the delay for the LCD is not suitable. We changed the value of the delay to make it more accurate when pushing the push button.

Conclusion 

In this mini project, the objective is to appreciate the hardware and software interfacing of a microcontroller system. Besides that, the aim is to design, write and test an assemble programming which meets a technical specification in a given target system. Throughout this mini project we have learn on how to apply all of our basic knowledge in the making of the flowchart, designing circuit, write program and assemble the program. Thus, the objective is achieved. By constructing both software and hardware, we have learned on how the process of making the stopwatch with lap times.

             Next, the objectives of the project are also achieved as we successfully make a fan that automatically regulated by the detected temperature and also successfully make this project using 8051 Microcontroller system. Furthermore, this mini project has taught us on how to appreciate the software interfacing of a microcontroller system. So, we can conclude that the entire objectives are achieved.  

References

1. The 8051 microcontroller and embedded system using assembly and C by Muhammad Ali Mazidi
2. http://www.ece.utep.edu/courses/web3376/Lab_5_-_LCD.html
3. Lecture notes