STOPWATCH WITH LAP TIMES (MINI PROJECT MICRO C)

OPERATION SYSTEM STOPWATCH WITH LAPTIMES

By using Silicon Lab Toolstick850, a stopwatch is a handheld timepiece designed to measure the amount of time elapsed from a particular time when activated to when the piece is deactivated. A large digital version of a stopwatch designed for viewing at a distance, as in a sports stadium, is called a stop clock.

The timing functions are traditionally controlled by two buttons on the case. Pressing the top button starts the timer running, and pressing the button a second time stops it, leaving the elapsed time displayed. A press of the second button then resets the stopwatch to zero. The second button is also used to record split times or lap times. When the split time button is pressed while the watch is running, the display freezes, allowing the elapsed time to that point to be read, but the watch mechanism continues running to record total elapsed time. Pressing the split button a second time allows the watch to resume display of total time. Mechanical stopwatches are powered by a main spring, which must be periodically wound up by turning the knurled knob at the top of the watch.

Digital electronic stopwatches are available which, due to their crystal oscillator timing element, are much more accurate than mechanical timepieces. In case, silicon lab toolstick850 already have in toolstick850. Because they contain a microchip, they often include date and time-of-day functions as well. Some may have a connector for external sensors, allowing the stopwatch to be triggered by external events, thus measuring elapsed time far more accurately than is possible by pressing the buttons with one's finger. The device is used when time periods must be measured precisely and with a minimum of complications. Laboratory experiments and sporting events like sprints are good examples.

OBJECTIVE PROJECT

To appreciate the hardware and software interfacing of a microcontroller system.

To design, write and test an assembly programming which meets a technical specification in a given target system.

· To investigate how to use silicon lab Toolstick850.

· To demonstrate the project how it works and build a fully functional stopwatch.

· To train and create a new project from the hardware and simplicity studio software.

FLOWCHART

Process of program stopwatch

SOFTWARE FUNCTIONAL BLOCK DIAGRAM

ANALYSIS

From the mini project, use PROTEUS to create a circuit of this mini project “STOPWATCH WITH LAP TIMES” and create coding using KEIL and run with Simplicity studio to run and burn the program C. Firstly, the circuit always have some basic error because got a little mistake when solder it. We use a Toolstick850 replace IC8051 because this Toolstick850 is easy then IC8051. Stopwatch basically plays with time minutes, second and miliseconds so the time should be running accurate. We got some error from a conversion programmer from KEIL to SIMPLICITY STUDIO, stand still we change some instructions on coding C. Basically, the 2 x 16 LCD works on 4-bit or 8-bit data line and three control lines. Now we use LCD for 4-bit because it’s easy to check the error. The control lines are RS, R/W and E. All communication between 2 x 16 LCD and host processor is synchronized by E line. For this Toolstick850 we change the connection port. Port LCD we use P0.0 to P0.7 in Toolstick850. The output can be in result as we keep this program.

CONCLUSION

The STOPWATCH has been using a system of "Proteus VSM software" to get the schematic diagram. Use code on Keil software uVision4 and Simplicity Studio. In addition, developing a code by using the output of 2x16 LCD unit using ic8051 develop tools for measuring analog equipment. STOPWATCH time tracking system for a setting that is programmed using coding C system. This STOPWATCH has been set to two rounds of LAB at coding and displayed by the LCD display. Each connection appearing in the circuit by using strips board because it is easier to identify the error that will occur. For STOPWATCH can learn how it works by using a microcontroller program.