Im new to da world of muc. i want to noe the know how of your circuit.... cud u please enlighten me..... thank u

the circuit has a keypad, LCD and a controller..
what you did not understand in the circuit? what part is not clear to you.. please provide more details about your doubt.

I have been told to prepare a project and explain it even before learining what a muc is.... that's how they teach us..... so if you have a ready-to-post abstract of the working of the project i would be very grateful because even though i cud get information on it, the time constraints bind me....

Im a third year,6th semester, electronics and telecomm student.... i noe mups... muc is a new subject

well i do not make any abstracts or anything like that.. but the working is simple..
for keypad and its working read the keypad tutorial
and for LCD read the LCD tutorial. Tutorials are located over here....
http://www.8051projects.net/microcontroller-tutorials/

it will give you complete working of keypad and LCD and the circuit consist of these components only... so you wont have any problem understanding the codes..

give feedbeck on digi lock using lcd & keypad.. is it working on the first run

yes its working.. in comment section you can see two people got it working on the first run. But Please construct your hardware very carefully. Normally hardware creates problem.

@ajay
thanx 4 replyin .... sir m using 4x3 SPST switches keypad....... i made it my self . is it ok to use spst switches . also u dont mention ny datasheet of LCD tht ur usin. Which lcs shud b used

LCD is general purpose.. 2x16 LCD alpha numeric.

and the reason i provided the keypad circuit is so that you can make it yourself. Try to run the hardware to see if its working. Make sure your connections are tight..

sir thanx 4 the previous replies........ plz explain me the code of digital lock using keypad & lcd . in the LCD.C, y u made lockicon,unlockicon,ok,ex(the hex no. wht r they for).....

when you run the program you will come to know.
lockicon, unlockicon, ok and ex are arrays to create custom character for LCD. Just check the LCD tutorial for how the hex values are calculated.

23.jpg

sir, i hv used the switch(shown in red circle) for making the 4x3 keypad.......... is it ok to use these... wil it work

if its a push button then it will work..
i.e. if you press button, it should not stay there.. it must come back to normal position after release.

hi sir........... thanx 4 replyin so quickly. its great.
sir actually in the lab we hv a controller board(made by advanced technology). its got faullty. now our evaluation is on thursday. so we hv to show it on KEIL.So we did it... but we dont know wht to enter in the ports at which iinstant as algo. of this program is not clear to me. So plz tell me the steps to simulate it....... so tht Sir wil be convinced tht i hv understood the program and its working..

its very hard to simulate it in keil.
you need to enter key with row and column combination. I cannot explain this coz its not easy to explain even.

wht 2 do.................then

If you have access to a 2051 programmer,just build the circuit.Would hardly take a couple of hours and a couple hundred bucks.

finish the circuit, burn the program.. and run it.. Project Done

anybudy help me about reading contents of LCD.......
my project is digital lock.....

what kind of lcd content?

sorry sir ,
actually i m working on digital key lock project.
i thought that i will get data displayed on LCD to compare password stored in EEPROM..
can u send me the C code of this project & circuit diagram....

password stored in eeprom?
i did not make that project yet. but when i make it.. i will surely upload it.

right now i have only the simple code lock project

thanks for having this prototype posted here.. i just want to ask something.. are the two capacitors near the crystal oscillator 33uF or 33pF??.. if those are 33pF, then there is no available electrolytic capacitor with such rating.. the schematic symbol of those two represents an electrolytic one, as can be seen in the schematic diagram.. are those capacitors electrolytic or ceramic?? thanks again!

migs, sorry if my schematic makes you think that way.
Those are 33pF ceramic capacitors. If they are not available then you can try looking for 22pF. I will recheck the schematic and make the changes if needed.
Thanks!

sir,
the code limit of ic is 2k.but the size of hex file is more than it then what to do....?

hi singh,
if u are talking of the hex file size shown on the PC, then u need not worry as that has no relation to the actual size of the code being downloaded to the uC.The code size is actually the no. of machine language op-code bytes ( u can see them on the PC if u open the hex file using notepad) and the hex file size shown in the windows explorer is the size occupied by the hex file on the hard disk of ur PC.

Sir Ajay, im having a project which is similiar with the one you have uploaded,it is given that the design involves a microcontroller interfaced to a LCD and Keypad which activates an output line based on the key-code combination given to the input. The system works as a electronic lock with a user key and a master key. The master key is used to change the user keys, while the user keys are used to open or close a door or a set of doors.

it has 3 doors, i need to have 8 set of key, 1st set of key will open door A, 2nd open the B, 3rd open C, 4th open A&B, 5th open B&C, 6th open A&C, 7th open ABC, 8th is the master key.

for the securities features, when the user enters a wrong key, the system should warn the user using a short beep. If the user enters wrong keys consecutively for the third time, the system should enable a red LED. Any key pressed should be discarded and the system should beep on press of any key.

may i know that what is the difference between my assigment, with the one you made ? it seems that it is the combination of your project, Digital Code lock with LCD and Keypad using AT89C2051 and the 1 Mr Binu J did, Microcontroller Based Digital code Lock (AT89C2051). is there any hardware that i need to add in my project ? For the programming part, which part is it should i modify ?

anyone pls answer my question ? im facing big problem to start this project because i've never study anything about up & uc before this.. it seems very difficult for a beginner , but i would try my best to finish it ! Thanks alot to those who are willing help me !

bkwu, i really suggest you to go through your study material first as that is something which is needed for you. Later on you can try your hands on programming microcontroller.Also side by side try working on C too.

also, regarding guidance and help, We are always here to help you. I am sure you will do best.
Best of luck!

ok thanks alot for the advise. i have roughly read through the book since i had an exam few weeks ago. im going to have group discussion to do the PCB diagram & the flow chart tonight. Then will start to do the hardware and software starting from tmr. will ask you here if i face any problem ! thanks ~

sure, you can ask queries anytime always here..

erm sir, could you list out the component of your project for me ? cause i dont know whats the name of the component, i need to buy it to build my hardware. should i add a piezo transducer or loudspeaker to make it to create the sound 'beep' ? To have the LED to replace the gate, means that i need to have total of 3 LED ? what is the component Y1 11.0592MHz ? is that the piezo transducer ?

11.0592Mhz is crystal used to provide clock to controller. I am really surprised that you dont know about loudspeaker, but anyways, you can tell the shopkeeper to give you buzzer or a beeper, this buzzer is same speaker you have in your CPU (computer). you can go to spare shop for computers and look for that beeper or computer speaker or buzzer.

can you help me to check does this schemetic diagram fit with what i want ?

there seems to be some problem with image you posted, i am not able to open it. can you use www.imageshack.us to upload image?

http://img56.imageshack.us/img56/425/schemeticdiagramtm8.jpg

well in that schematic, you mentioned at89c2051, where that controller does not have port 2 in it. however you can use a different controller instead of at89c2051 like at89c51 which has 4 ports, keeping all the connections same. You need to edit the code further to make those relays work.

now regarding schematic, simply remove those LEDs from base of transistors. also drive speaker o/p using transistor instead of driving it from controller as controller wont be able to provide enough current.

hi mr.ajay.. let say my c language for particular project done..
so, my question here,do we have any related software to convert this C to ASM..
if so, can u give me a link.

sir, now we are facing another problem with the lcd.
may i know how can i display * on the lcd ? i mean what is the code for '*'
and then how to display more than 1 '*' ? do i need to MOV A, #'*' to the lcd for 3 times if i wan to display 3 * ?
because we are trying to make it to display a * on the lcd when input 1 character, 2 '*' when input 2 char and so forth.
we appreciate anyone who could help us to solve the question. thanks !

for each input character from keypad you can Echo a * on the LCD.


Arun

Do like this, copy the getinput routine and paste it in the same file with name getpasswordinput, keeping everything same, just while sending data to lcd, send '*' instead of key number.