project guidence

[inder_singh_40]

sir. iam making a project of electronic voting machine based on AT89S8252 microcontroller, i have ordered for making pcb and purchased the components req. but actually i dont know the working of this project that how votes are entered and finnaly how they can be viewed after after finish of voting process. please help me out im attaching hex file ckt diagram and assebly file along with my messege please help me out, i will be very thankfull to u. thanks

 

[duffy]

The keypad and displays are matrixed, the keys read the vote selection and accept a password for reading and clearing totals, the speaker beeps if you choose the wrong candidate.

 

[inder_singh_40]

reply

thanls sir, but i want toknow that how iam able to insert to password or how i can create it

 

[duffy]

I am not going to help you hack a voting machine.

 

[blueroomelectronics]

Hack, I think the OP is expecting someone just happens to have firmware that does exactly what he wants ready to go. Not likely.

 

[Joesamuel]

micro controller are highly based upon the programming you can put password for this..
If you configure the port 1 as the input port then assign a pin , if the pin is logic high then only allow the port 3 which has keyboard interface,then connect a EPROM IC in the remaining pins of the Port1 and program the IC as a text signaling input.then accordingly you program the micro controller also...It will work....

 

[duffy]

You can also get 4 port pins back by combining the 4 display and switch strobes. They can do double-duty in this design.

Look on the Atmel site for Display/Keyboard readers. They may already have some code routines written for display drive and switch debounce.

But I wouldn't suggest that particular chip - it doesn't have EEPROM. If you get one with EEPROM memory so you can save the password and voting totals to it without having to interface an external chip. This would also make it more secure, because it's easier to read an external serial EEPROM than one built into a microcontroller with a code protection fuse and a password.