Microcontroller Based Digital Clock with Alarm

AT89S51/52 based Digital Clock without any Clock IC. It have 4 seven segment display to display the Time.

Components Used:


Circuit Diagram:

Program: View attachment RTC_CLOCK.zip

Thank you for the very Good Project.
Please would you upload flow-chart or detailed algorithm for any project. We want here in our site to learn everybody how to DESIGN the basic steps in any design is not just the code "asm, C bas". We need to upload the idea of any project.

Thanks so much.

Yes i understand it, but i dont get time to do that. because there are projects greater than 50. I will try to do.
Members can contribute them. I can check it and post here.

hi there BInu..

i know that the topic to ask is old topic. but i need your idea about the collage bell. i would like to ask is that what is the meaning of "330E" in the circuit of collage bell. what is the actual value of the resistor there?? and also the 100E,12V in the relay.. can u pls help us about this,i have the problem i buying the components.

and another thing can we use AT89S52 insted of AT89S8252??? and what other iC's Alternative can we use for the circuit??

can u pls also send your reply in my email add.. harharatciscoclass@yahoo.com.ph
im first timer hire in the forum. i dont actually see the reply and my post hir.

hi there Binu..

this about the automation of Collage Bell. i know that it is a old topic but i need your help.. im going to ask what is tha meaning of the "330E" in the circuit of collage bell. what is the actual value of the resistor there? and also the 100E,12V at the relay.. can you pls help us.. cause we have problem in buying the components..

and another thing is that do we can use the At89S52 as AT89S8252??? we dont see that IC at the store hire. pls do reply in this topic hir at the furom and in

my email: harharatciscoclass@yahoo.com.ph

because im new in the forum room hir. i dont actually see my post and reply.. tnx i hope for ur reply soon..

E corresponds to ohm

No you cant use, check here for more about the project.
http://www.8051projects.info/forum/topic.asp?TOPIC_ID=43

thanks for reply.. we decided to enlarge the 7 segment display. the display we buy is 12V, we need to enlarge the 5V to 12V.. where do you thing we put the step up transformer in your circuit??? (at the transistor to 7segment??)

and how about the program... what programing software/environment/or language is it?? actually i can open it to view the program.. and do you have suggestion or recmmendation for the improvements of the project.

brother Binu, dont be tired to reply on us cause we really need you in our study. . thank you very much..

You can use Driver IC for Each segments use ULN2003 which have 7 drivers inside, so you need 4 driver IC's.

The Program is written on BASIC language, for more details about the compiler visit www.mcselec.com

hi der BINU.what's up...

i have another question about the automated collage bell..
how the DS1307 starts its real time? how do i know what is the starting actual time of DS1307 when i test the circuit?? will the 7-segment display the real time??

here in PHILIPPINES class start at 7:30am, the project will be ON early than 7:30am,e.i 7:00am. is the DS1307 clock will start at 7:00am?? pls reply about this confusesion.

and another thing, how key pad work or function to program the desire time?

Mostly the DS1307 starts on 00:00:00
You can enter new timings using the buttons