Digital Alarm Clock
Introduction:
In this design assignment the aim is to build a digital alarm clock which is able count automatically the hour, minutes and seconds and for an advanced version it will give the user the option to set the timer, count the year, triggering the alarm when the specified time is reached and implement the daylight saving s mode (which is hour count decrement when the daylight savings mode is off). In case of the supreme clock there will be an option to set the date and with every 24 hours passed the day count will be increased. Also, for a more advanced design the leap years can be included.
Design:
The total clock circuit is designed using Logisim software where main circuit composed of three circuits the upper segment circuit, a decoder circuit and a lower segment circuit. For turning ON the clock the ticks of Logisim clock is enabled. The clock design gives the user to set the hours, minute and second individually and the time of day is displayed through AM and PM. The designed decoders are used in the Upper segment subcircuit along with various flip flops and basic gates with a clock. The lower segment subcircuit contains only some splitters, outputs and basic gates. Finally, the three subcircuits are used to make the final clock circuit as given below.
Lower segment circuit:
Decoder circuit:
Upper segment circuit:
Main clock circuit:
Conclusion:
Hence, by conclusion it can be said that the digital clock is designed in limited time and with minimum number of inputs and outputs to reduce complexity of the system. As the decoder available in the circuit is not meeting the input output requirements and logical implementation requirement, hence the decoder circuit is built in subcircuit. The decimal display of hour, minute and second is displayed using the 7 segment displays and LED arrays. Similar logic can be applied with additional component to update the clock as a supreme clock with calendar year, alarm display and other special requirement.
