RTC based Digital Clock with Seven Segment Display with 12 24 Hours Mode (Electronic project)

RTC based Digital Clock with Seven Segment Display with 12 / 24 Hours Mode

TECHNICAL SPECIFICATIONS:

Title of the project                  :           RTC based Digital Clock with Seven Segment

Display with 12 / 24 Hours Mode

Domain                                   :           Embedded Systems Design

Software                                  :           Embedded C, Keil, Proload

Microcontroller                       :           AT89S52

Power Supply                          :           +5V, 750mA Regulated Power Supply

Display                                    :           Seven Segment Display

Crystal                                     :           11.0592MHz

Applications                            :           Office / Industries / Colleges / Hospitals

Abstract:

A digital clock is a type of clock that displays the time digitally, i.e. in ciphers, as opposed to an analog clock, where the time is displayed by hands. Usually, digital clocks are associated with electronic drives. 

Digital clocks typically use the 50 or 60 hertz oscillation of AC power or a crystal oscillator as in a quartz clock to keep time. Most digital clocks display the hour of the day in 24 hour format but in  few other countries a more commonly used hour sequence is 12 hour format (with some indication of AM or PM)

In this project to represent the time, we are using Seven- segment Display for each of four digits which shows hours and minutes and in order to represent seconds we are using LED’s for each and every seconds led starts blinking. Moreover, since they run on electricity, most digital clocks must be reset every time they are moved or the power is cut off. This is a particular problem with alarm clocks, since a power outage during the night usually results in the clock failing to trigger the alarm in the morning.

To reduce the problem, they often incorporate a battery backup to maintain the time during power outages for this we are using a RTC (Real Time Clock).

In this we are using three switches, one for entering the time, second for incrementing and the third for decrementing the time we are also using one sliding switch to change the mode i.e., AM/PM. Whenever we want to enter the time by default we need to set in 24 hour mode.

This digital clock are very small and inexpensive devices that make product designs more popular, they are often incorporated into all kinds of devices such as radios, televisions, microwave ovens, standard ovens, computers and cell phones. 

This project uses regulated 5V, 500mA & 12V, 500mA power supply. 7805 and 7812 three terminal voltage regulators are used for voltage regulation. Bridge type full wave rectifier is used to rectify the ac output of secondary of 230/12V step down transformer.

Block Diagram: