Digital clock are widely used nowadays. The usual method for programming the clock as we have all seen is the ‘SOFTWARE DELAY’ or ‘POLLING’ method generated by using looping statements such as FOR and WHILE loop. But the major drawback with this type of program is that the delay of the other instructions goes on summing every time resulting in elongated delay than required. Thus after a handful amount of time, it seems as if the Clock has slowed down. To overcome this we will use Timer with interrupt to generate delay.This project is basically divided into three parts: Controller, LCD and Keypad. The 16×2 LCD has inbuilt Hitachi’s HD44780 controller to process the data and the Keypad is configured in (4×1) fashion. This means the 4 keys are connected to four different pins having a common ground. More-over, 1 second delay is achieved by using TIMER-1 Interrupt of ATmega16.
Embedded Systems are widely used nowadays. Applications of the embedded system are innumerable. One such application as discussed here is Lift Overload Indicator. As the name implies, it restricts the elevator from transporting a number of people above the maximum prescribed limit.The indicator used here is RGB led to indicate the warning signs. Moreover, it also displays the net number of people in the elevator using an LCD in 4-bit mode. The counting of the person is accomplished by using two IR sensors. We know that using the three primary colours Red, Blue and Green, any secondary colour can be obtained. The RGB led uses the same principle. Different colours are generated by mixing of different intensities of the three primary colours. Keep on reading to find out how the project is assembled and tested.