RFID Based Access Control System using 8051

jojo August 13, 2017 8 Comments

RFID Door Access Control System using 8051

In this project, we are going to build an RFID Based Access Control System using 8051 Micro Controller. The same system can be named like RFID based door lock or RFID based access management system. If you have been to big hospitals or companies, you might have seen how they used RFID based locks to restrict access to certain areas. In hospitals, only hospital staff with approved RFID tags can access Intensive Care Unit and such restricted areas. So let’s begin to build the system.

Before reading further, you need to fully understand How to Interface RFID Reader to 8051 Microcontroller. Read this article before you attempt to make RFID based access control system.

Project Description

A RFID based Door Lock or Access Control System is based on some simple concepts. We store a set of RFID card data in our system, say 3 or 10 RFID card data. When the person with the right RFID card (compatible to data preloaded in our program/system) come and swipes his RFID tag, access will be granted. When the person with the wrong RFID card (whose data is not loaded in our system) swipes his RFID tag, access will be denied. I hope you understand the system concept of RFID based Door Lock.

RFID Based Door Lock using 8051

RFID based Access Control using 8051

The full circuit diagram for interfacing RFID module to 8051 is shown above. The unique ID code in the RFID card is read by the circuit and displayed on the 16×2 LCD display. Tx pin of the RFID module is connected to Port 3.5 of the microcontroller. The microcontroller receives data from the RFID module through this channel. Switch S1, capacitor C1 and resistor R1 forms the reset circuit. Capacitor C2, C3 and crystal X1 are associated with the reset circuit.

The Program

 RS EQU P2.7
RW EQU P2.6
E  EQU P2.5
FLG EQU 40H
SEL EQU 41H

ORG 000H
CLR P2.0
MOV TMOD,#00100001B
MOV TH1,#253D
MOV SCON,#50H
SETB TR1
ACALL LCD_INIT
MOV DPTR,#TEXT1
ACALL LCD_OUT
ACALL LINE2
MOV DPTR,#TEXT2
ACALL LCD_OUT

MAIN:ACALL LCD_INIT
     MOV DPTR,#TEXT1
     ACALL LCD_OUT
     ACALL LINE2
     MOV DPTR,#TEXT2
     ACALL LCD_OUT
     ACALL READ_TAG
     CLR REN
     ACALL LINE2
     ACALL CHECK_PASSWORD
     ACALL DELAY1
     SETB REN
     SJMP MAIN
     
     
LCD_INIT: MOV DPTR,#INIT_COMMANDS
          SETB SEL
          ACALL LCD_OUT
          CLR SEL
          RET      

LCD_OUT:  CLR A
           MOVC A,@A+DPTR
           JZ EXIT
           INC DPTR
           JB SEL,CMD
           ACALL DATA_WRITE
           SJMP LCD_OUT
CMD:      ACALL CMD_WRITE 
           SJMP LCD_OUT
EXIT:	   RET          

LINE2:MOV A,#0C0H 
    ACALL CMD_WRITE
    RET   
    
 READ_TAG:  MOV R0,#12D
           MOV R1,#160D
	   WAIT:JNB RI,WAIT
           MOV A,SBUF
           MOV @R1,A
           INC R1
           CLR RI
           DJNZ R0,WAIT
           RET
   

CHECK_PASSWORD:	CLR FLG
      		MOV R2,#12D
      		MOV R1,#160D
      		MOV DPTR,#PASS1
	REPEAT: CLR A
      		MOVC A,@A+DPTR
      		XRL A,@R1
      		JNZ CHECKNEXT
      		INC R1
      		INC DPTR
      		DJNZ R2,REPEAT
      		ACALL LINE2
      		MOV DPTR,#TEXT3
      		ACALL LCD_OUT
      		SETB P2.0
      		RET
      
CHECKNEXT: JB FLG,FAIL
           MOV R2,#12D
           MOV R1,#160D
           MOV DPTR,#PASS2
           SETB FLG
           SJMP REPEAT


FAIL:ACALL LINE2
     MOV DPTR,#TEXT4
     ACALL LCD_OUT 
     CLR P2.0
     RET
    
 

DELAY1:MOV R3,#46D
BACK:  MOV TH0,#00000000B   
       MOV TL0,#00000000B   
       SETB TR0             
HERE1: JNB TF0,HERE1         
       CLR TR0             
       CLR TF0             
       DJNZ R3,BACK
       RET


CMD_WRITE: MOV P0,A
    CLR RS
    CLR RW
    SETB E
    CLR E
    ACALL DELAY
    RET

DATA_WRITE:MOV P0,A
    SETB RS
    CLR RW
    SETB E
    CLR E
    ACALL DELAY
    RET

DELAY: CLR E
    CLR RS
    SETB RW
    MOV P0,#0FFh
    SETB E
    MOV A,P0
    JB ACC.7,DELAY
    CLR E
    CLR RW
    RET
    
INIT_COMMANDS:  DB 0CH,01H,06H,83H,3CH,0    
TEXT1: DB "RFID ACCESS",0  
TEXT2: DB "Swipe TagS..",0
TEXT3: DB "Access allowed",0
TEXT4: DB "Access denied",0

PASS1: DB "18008DC02E7B"
PASS2: DB "7500511ECDF7"
   
    END

The program is self-explanatory.

Project Kit – RFID Access Control System

RFID_GraphicsButton_View_Project_Kit

 

Comments
  • Thanh Tam
    May 14, 2016

    This code cant work? I was try on Proteus. Someone can fix this code?

    • jojo
      May 18, 2017

      The code is perfectly working!

  • saurav
    February 16, 2016

    can this project work

  • shaswata saha
    February 15, 2016

    rfid based access control pricing and related details.

  • joshi chaitali rajendra
    January 10, 2016

    please suggest innovative topic for mini project for E&TC

  • Lawrence Woods
    November 11, 2015

    Can I have the c code for this application?

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