Programmable number lock using Microcontroller

Programmable number lock system

APPLICATION: The ‘Electronic device number lock’ system is a high security system.The main application kept in mind during the design of this system is to secure expensive electronic devices and machinery. The access to such devices can be restricted to particular users only. The system is highly secured since the code can be changed every time the user locks it. This can also be used an physical lock by using solenoid and thus can be used to lock safes in banks or other institutions. Regular electronic number lock available in the market can lock/unlock just one device, but this design can lock/unlock up to nine devices.
The program used for the operation of this system is as follows : ;*************************************************************; PROCEDURE OF WAIT ;*********************************************************** org 8500h wait: push dph push dpl push r0 push r1 mov dptr,#2042h ;input data from PORT C wi: movx a,@dptr mov r2,a anl a,#20h jz cont ;check for interrupt from display unit jmp start cont: mov a,r2 anl a,#0fh ;to check whether any key is pressed jz wi mov r0,#75 lcall 6798h mov dptr,#2042h here: movx a,@dptr ;wait for the key to be realesed jnz here mov dptr,#2040h ;sending a pulse to the display section mov a,r2 movx @dptr,a mov a,#00h mov dptr,#2041h movx @dptr,a mov a,#40h movx @dptr,a mov a,r2 mov r0,#75 lcall 6798h pop r1 pop r0 pop dpl pop dph ret ;***********************************************************; STORING AND RETRIVING OF PASS WORD ;*********************************************************** org 8550h scan: mov r0,#04h mov dptr,#2042h one: movx a,@dptr ;check for lock or unlock buttons anl a,#0c0h jz one ret lock: lcall wait ;storing of pass word in given location mov @r1,a inc r1 djnz r0,lock lcall out ret unlock: clr 0ah call wait mov a,@r1 xrl a,r2 ;comparing the entered and the stored code jz match setb 0ah ;in case of mismatch set error bit match: inc r1 djnz r0,unlock jnb 0ah,go mov a,#20h push dptr mov dptr,#2040h movx @dptr,a push r0 push r1 mov r0,#ffh lcall 6798h pop r1 pop r0 mov a,#00h movx @dptr,a pop dptr jmp not go: lcall out not: ret ;***********************************************************; TO ACCEPT THE DEVICE NUMBER ;*********************************************************** org 9000h mov sp,#05fh main: clr 01h ;clearing all the device flags clr 02h clr 03h clr 04h clr 05h clr 06h clr 07h clr 08h clr 09h setb ie.7 setb ie.2 start: mov a,#89h ;C as i\p,A and B as o\p mov dptr,#2043h movx @dptr,a mov r7,#05h ;clearing the display section rss: mov dptr,#2040h mov a,#00h movx @dptr,a mov a,#00h mov dptr,#2041h movx @dptr,a mov a,#40h movx @dptr,a djnz r7,rss lcall wait cjne a,#01h,nxt2 jmp dev1 nxt2: cjne a,#02h,nxt3 jmp dev2 nxt3: cjne a,#03h,nxt4 jmp dev3 nxt4: cjne a,#04h,nxt5 jmp dev4 nxt5: cjne a,#05h,nxt6 jmp dev5 nxt6: cjne a,#06h,nxt7 jmp dev6 nxt7: cjne a,#07h,nxt8 jmp dev7 nxt8: cjne a,#08h,nxt9 jmp dev8 nxt9: cjne a,#09h,start jmp dev9 ;***********************************************************; SELECTED DEVICE ACTIVATION ;*********************************************************** org 9200h dev1: mov r1,#30h ;Loading the address of the password mov r3,#01h ;device no. used to give to the decoder lcall scan cjne a,#80h,unlock1 ;check for the lock\unlock pressed jmp lock1 unlock1: jnb 01h,error1 ;generating error if the selected device is already ;activated lcall unlock jb 0ah,hr1 clr 01h ;clear lock\unlock flag hr1: jmp start lock1: jb 01h,error1 lcall lock setb 01h ;set lock\unlock flag jmp start error1: mov a,#40h ;activating the error LED mov dptr,#2040h movx @dptr,a push dptr push r0 push r1 mov r0,#ffh lcall 6798h pop r1 pop r0 pop dptr jmp start ;*********************************************************** dev2: mov r1,#035h mov r3,#02h lcall scan cjne a,#80h,unlock2 jmp lock2 unlock2: jnb 02h,error2 lcall unlock jb 0ah,hr2 clr 02h hr2: jmp start lock2: jb 02h,error2 lcall lock setb 02h jmp start error2: mov a,#40h mov dptr,#2040h movx @dptr,a push dptr push r0 push r1 mov r0,#ffh lcall 6798h pop r1 pop r0 pop dptr jmp start ;*********************************************************** dev3: mov r1,#03ah mov r3,#03h lcall scan cjne a,#80h,unlock3 jmp lock3 unlock3:jnb 03h,error3 lcall unlock jb 0ah,hr3 clr 03h hr3: jmp start lock3:jb 03h,error3 lcall lock setb 03h jmp start error3: mov a,#40h mov dptr,#2040h movx @dptr,a push dptr push r0 push r1 mov r0,#ffh lcall 6798h pop r1 pop r0 pop dptr jmp start ;*********************************************************** dev4: mov r1,#040h mov r3,#04 lcall scan cjne a,#80h,unlock4 jmp lock4 unlock4:jnb 04h,error4 lcall unlock jb 0ah,hr4 clr 04h hr4: jmp start lock4:jb 04h,error4 lcall lock setb 04h jmp start error4: mov a,#40h mov dptr,#2040h movx @dptr,a push dptr push r0 push r1 mov r0,#ffh lcall 6798h pop r1 pop r0 pop dptr jmp start ;*********************************************************** dev5: mov r1,#045h mov r3,#05h lcall scan cjne a,#80h,unlock5 jmp lock5 unlock5:jnb 05h,error5 lcall unlock jb 0ah,hr5 clr 05h hr5: jmp start lock5:jb 05h,error5 lcall lock setb 05h jmp start error5: mov a,#40h mov dptr,#2040h movx @dptr,a push dptr push r0 push r1 mov r0,#ffh lcall 6798h pop r1 pop r0 pop dptr jmp start ;*********************************************************** dev6: mov r1,#04ah mov r3,#06h lcall scan cjne a,#80h,unlock6 jmp lock6 unlock6:jnb 06h,error6 lcall unlock jb 0ah,hr6 clr 06h hr6: jmp start lock6:jb 06h,error6 lcall lock setb 06h jmp start error6: mov a,#40h mov dptr,#2040h movx @dptr,a push dptr push r0 push r1 mov r0,#ffh lcall 6798h pop r1 pop r0 pop dptr jmp start ;********************************************************** dev7: mov r1,#050h mov r3,#07h lcall scan cjne a,#80h,unlock7 jmp lock7 unlock7:jnb 07h,error7 lcall unlock jb 0ah,hr7 clr 07h hr7:jmp start lock7:jb 07h,error7 lcall lock setb 07h jmp start error7: mov a,#40h mov dptr,#2040h movx @dptr,a push dptr push r0 push r1 mov r0,#ffh lcall 6798h pop r1 pop r0 pop dptr jmp start ;******************************************************* dev8: mov r1,#055h mov r3,#08h lcall scan cjne a,#80h,unlock8 jmp lock8 unlock8:jnb 08h,error8 lcall unlock jb 0ah,hr8 clr 08h hr8: jmp start lock8:jb 08h,error8 lcall lock setb 08h jmp start error8: mov a,#40h mov dptr,#2040h movx @dptr,a push dptr push r0 push r1 mov r0,#ffh lcall 6798h pop r1 pop r0 pop dptr jmp start ;******************************************************* dev9: mov r1,#05ah mov r3,#09h lcall scan cjne a,#80h,unlock9 jmp lock9 unlock9:jnb 09h,error9 lcall unlock jb 0ah,hr9 clr 09h hr9: jmp start lock9:jb 09h,error9 lcall lock setb 09h jmp start error9: mov a,#40h mov dptr,#2040h movx @dptr,a push dptr push r0 push r1 mov r0,#ffh lcall 6798h pop r1 pop r0 pop dptr jmp start ;******************************************************* ; OUTPUT SECTION ;******************************************************* org 0a000h out: mov a,r3 ;loading the device number mov dptr,#2041h movx @dptr,a ret ;********************************************************* This program is assembled using DASM assembler and the hex file is downloaded to the 8051 microcontroller kit. 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