Toll plaza system based on vehicle category interface with 8051 microcontroller (AT89C51)

 

This topic is an extension to Simple toll plaza system. The toll amount is charged based on the category of the vehicle driving through the plaza. The vehicle categories taken here are two-wheeler & four-wheeler. When a user scans his ID at the toll plaza, some amount is charged from his account depending upon his vehicle category. User also has the facility to recharge his account.

The project has been developed by interfacing RFID with AT89C51. The relevant messages are also displayed on a 16x2 LCD. The free source code for the program is available in C.

Simple toll plaza system charges the toll tax from the user irrespective of the type of his vehicle. This project also considers the vehicle type while charging the toll amount. The RFID tag is used as a unique identity for account of a particular user.

 C Code:

//Program for Toll plaza system based on vehicle category interface with 8051 microcontroller (AT89C51)

#include<reg51.h>

#define port P1

#define key        P0                             // Port for keypad

void memory();

sfr lcd_data_pin=0xA0;

sbit rs = P1^3;

sbit rw = P1^4;

sbit en = P1^5;

sbit col1=key^4;

sbit col2=key^5;

sbit col3=key^6;

sbit row1=key^0;

sbit row2=key^1;

sbit row3=key^2;

sbit row4=key^3;

unsigned int number=0,pointer=1;

unsigned char card_mem[4][12];

unsigned char card_id[12],index=0,key1=0,lcd,print=0,new_user=0,recharge=0,user_index,t,tool=0,type=0;

unsigned int amount[4];

unsigned char card_type[4];

unsigned char current_byte = 0,money[6];

unsigned char pos=0,set=0;

void delay(unsigned char count)               //Function to provide time delay

{

                unsigned int j;

                unsigned char i;

                for(i=0;i<count;i++)

                for(j=0;j<1275;j++);

}

void lcd_command(unsigned char comm)   //LCD command funtion

{

                lcd_data_pin=comm;

                en=1;

                rs=0;

                rw=0;

                delay(1);

                en=0;

}

void lcd_data(unsigned char disp)  //LCD data function

{

                lcd_data_pin=disp;

                en=1;

                rs=1;

                rw=0;

                delay(1);

                en=0;

}

lcd_string(unsigned char *disp) //LCD string function

{

                char x;

                for(x=0;disp[x]!=0;x++)

                {

                                lcd_data(disp[x]);

                }

}

void lcd_ini()                                                        //Function to inisialize the LCD

{

                lcd_command(0x38);                      

                delay(5);

                lcd_command(0x0F);       

                delay(5);             

}

void timer_on()

{

                TMOD=0x20;                                                                                                      //Enable Timer 1

                TH1=0xFD;

                SCON=0x50;

                TR1=1;

                IE=0x94;

}

void timer_off()

{

                TMOD=0x00;                                                                                                      //Disable timer 1

                TH1=0x00;

                SCON=0x00;

                TR1=0;

                IE=0x00;

}

void lcd_display(unsigned int val)

{

                unsigned char flg=0;

                lcd_command(0xCC);

                if(val==0)

                lcd_data('0');

                while(val>0)

                {

                                lcd=val%10;

                                val=val/10;

                                lcd_command(0xCC-flg);

                                lcd_data(lcd+'0');

                                flg++;

                }

                  

}

void recieve() interrupt 4             //Function to recieve data serialy from RS232

{

                card_id[current_byte]=SBUF;

                RI=0;                                                      // Reset the serial interrupt after recieving the byte

                current_byte++;             

}

void display(unsigned char value)

{

                lcd_command(0x80+pos);

                if(value==10 && type==0)

                {

                                print=1;

                }

                if(value==12)

                {

                                set=1;

                }

                if(type==0 && value<=2)

                {

                                set=1;

                                card_type[index]=value;

                                lcd_data('0'+value);

                                delay(250);

                }

                if(value<=10 && type==1)

                {

                                if(value<10)

                                {

                                                lcd_data('0'+value);

                                                money[pos]=value;

                                                pos++;

                                }

                                if(value==10)

                                {

                                                pos--;

                                                lcd_command(0x80+pos);

                                                lcd_data(' ');

                                                lcd_command(0x80+pos);

                                }

                }

}

check_col1()

{

                row1=row2=row3=row4=1;

                row1=0;

                if(col1==0)

                display(1);

                row1=1;

                row2=0;

                if(col1==0)

                display(4);

                row2=1;

                row3=0;

                if(col1==0)

                display(7);

                row3=1;

                row4=0;

                if(col1==0)

                display(10);

                row4=1;

}

check_col2()

{

                row1=row2=row3=row4=1;

                row1=0;

                if(col2==0)

                display(2);

                row1=1;

                row2=0;

                if(col2==0)

                display(5);

                row2=1;

                row3=0;

                if(col2==0)

                display(8);

                row3=1;

                row4=0;

                if(col2==0)

                display(0);

                row4=1;

}

check_col3()

{

                row1=row2=row3=row4=1;

                row1=0;

                if(col3==0)

                display(3);

                row1=1;

                row2=0;

                if(col3==0)

                display(6);

                row2=1;

                row3=0;

                if(col3==0)

                display(9);

                row3=1;

                row4=0;

                if(col3==0)

                display(12);

                row4=1;

}

keypad()

{

                row1=row2=row3=row4=0;

                if(col1==0)

                check_col1();

                if(col2==0)

                check_col2();

                if(col3==0)

                check_col3();

}

 

void show()                       

{

                unsigned char count,i,key,flag=0,in;

                unsigned int j;

                timer_off();

                lcd_command(0x01);                    

                for(i=0;i<index;i++)

                {

                                key=0;

                                for(count=0;count<12;count++)

                                {

                                                if(card_id[count]==card_mem[i][count])

                                                {

                                                                key++;

                                                }

                                }

                                if(key==12)

                                {

                                                flag=1;

                                                if((amount[i]<=10 && card_type[i]==1)||(amount[i]<=20 && card_type[i]==2))

                                                {

                                                                user_index=i;

                                                                lcd_string("Insuff. balance");

                                                                delay(250);

                                                                lcd_command(0x01);

                                                                lcd_string("To recharge");

                                                                lcd_command(0xC0);

                                                                lcd_string("press *");

                                                                for(in=0;in<250;in++)

                                                                {

                                                                                for(j=0;j<1275;j++)

                                                                                {

                                                                                                row1=row2=row3=row4=0;

                                                                                                if(col1==0)

                                                                                                {

                                                                                                tool=1;

                                                                                                recharge=1;

                                                                                                t=1;

                                                                                                keypad();

                                                                                                break;

                                                                                                }

                                                                                }

                                                                                if(t==1)

                                                                                break;

                                                                }

                                                                t=0;

                                                                lcd_command(0x01);

                                                                lcd_string("Scan your ID");

                                                                break; 

                                                }

                                                if(tool==0)

                                                {

                                                                lcd_string("Thank you User ");

                                                                lcd_command(0x8F);

                                                                lcd_data(49+i);

                                                                delay(250);

                                                                lcd_command(0x01);

                                                                if(card_type[i]==1)

                                                                {

                                                                                lcd_string("Charge 10.00");

                                                                                amount[i]=amount[i]-10;

                                                                }

                                                                if(card_type[i]==2)

                                                                {

                                                                                lcd_string("Charge 20.00");

                                                                                amount[i]=amount[i]-20;

                                                                }

                                                                lcd_command(0xC0);

                                                                lcd_string("Amt left  ");

                                                                lcd_display(amount[i]);

                                                                lcd_command(0xCD);

                                                                lcd_string(".00");

                                                                delay(250);

                                                                lcd_command(0x01);

                                                                if(amount[i]<=30)

                                                                {

                                                                                user_index=i;

                                                                                lcd_string("Low balance");

                                                                                delay(250);

                                                                                lcd_command(0x01);

                                                                                lcd_string("To recharge");

                                                                                lcd_command(0xC0);

                                                                                lcd_string("press *");

                                                                                for(in=0;in<250;in++)

                                                                                {

                                                                                                for(j=0;j<1275;j++)

                                                                                                {

                                                                                                                row1=row2=row3=row4=0;

                                                                                                                if(col1==0)

                                                                                                                {

                                                                                                                                recharge=1;

                                                                                                                                t=1;

                                                                                                                                keypad();

                                                                                                                                break;

                                                                                                                }

                                                                                                }

                                                                                                if(t==1)

                                                                                                break;

                                                                                }

                                                                }

                                                }

                                                t=0;

                                                lcd_command(0x01);

                                                lcd_string("Scan your ID");

                                                break;

                                }

                }

                if(flag==0)

                {

                                lcd_string("Wrong ID");

                                delay(100);

                                lcd_command(0x01);

                                lcd_string("New user press *");

                                new_user=1;

                }

                current_byte=0;

                tool=0;

                timer_on();

}

recharge_acc()

{   

                unsigned char pin;

                timer_off();

                type=1;

                lcd_command(0x01);

                delay(40);

                lcd_string("Enter balance");

                delay(250);

                lcd_command(0x01);

                while(set!=1)

                {

                                keypad();

                                delay(40);

                }

                set=0;

                lcd_command(0x01);

                lcd_string("Your balance is");

                for(pin=0;pin<=pos;pin++)

                {

                                number=number+money[pos-pin-1]*pointer;

                                pointer=pointer*10;

                }

                amount[user_index]=amount[user_index]+number;

                lcd_command(0xC0);

                lcd_display(amount[user_index]);

                lcd_command(0xCD);

                lcd_string(".00");

                delay(250);

                lcd_command(0x01);

                number=0;

                pointer=1;

                pos=0;

                timer_on();

                lcd_string("Scan your ID");

                type=0;

}

void memory()

{

                unsigned char i,key=0,count,pin,try=0;

                lcd_command(0x01);

                lcd_string("New user scan ID");

                current_byte=0;

                while(current_byte!=12);

                lcd_command(0x01);

                for(i=0;i<4;i++)

                {

                                key=0;

                                for(count=0;count<12;count++)

                                {

                                                if(card_id[count]==card_mem[i][count])

                                                {

                                                                key++;

                                                }

                                }

                                if(key==12)

                                {

                                                lcd_string("Sorry!");

                                                lcd_command(0xC0);

                                                lcd_string("Already an user");

                                                delay(200);

                                                lcd_command(0x01);

                                                lcd_string("Scan your ID");

                                                key=0;

                                                try=1;

                                                current_byte=0;

                                                break;

                                }

                }

                if(key<12 && try==0)

                {

                                key=0; 

                                for(i=0;i<12;i++)

                                {

                                                card_mem[index][i]=card_id[i];

                                }

                                current_byte=0;

                                lcd_string("Scan again");

                                while(current_byte!=12);

                                for(i=0;i<12;i++)

                                {

                                                if(card_mem[index][i]==card_id[i])

                                                {

                                                                key++;

                                                }

                                }

                                if(key==12)

                                {

                                                current_byte=0;

                                                timer_off();

                                                lcd_command(0x01);

                                                lcd_string("You are User");

                                                lcd_command(0x8C);

                                                lcd_data(index+49);

                                                delay(250);

                                                lcd_command(0x01);

                                                lcd_string("Press 1       2");

                                                lcd_command(0xC0);

                                                lcd_string(" 2whlr    4whlr");

                                                delay(150);

                                                lcd_command(0x01);

                                                while(set!=1)

                                                {

                                                                keypad();

                                                                delay(10);

                                                }

                                                type=1;

                                                set=0;

                                                lcd_command(0x01);

                                                lcd_string("Enter balance");

                                                delay(150);

                                                lcd_command(0x01);

                                                while(set!=1)

                                                {

                                                                keypad();

                                                                delay(40);

                                                }

                                                type=0;

                                                set=0;

                                                lcd_command(0x01);

                                                lcd_string("Your balance is");

                                                for(pin=0;pin<=pos;pin++)

                                                {

                                                                number=number+money[pos-pin-1]*pointer;

                                                                pointer=pointer*10;

                                                }

                                                lcd_command(0xC0);

                                                lcd_display(number);

                                                lcd_command(0xCD);

                                                lcd_string(".00");

                                                amount[index]=number;

                                                delay(250);

                                                lcd_command(0x01);

                                                number=0;

                                                pointer=1;

                                                pos=0;

                                                lcd_string("Scan your ID");

                                }

                                else       

                                {

                                                lcd_command(0x01);

                                                lcd_string("ERROR");

                                                delay(200);

                                                for(i=0;i<12;i++)

                                                {

                                                                card_mem[index][i]=0;

                                                }

                                                lcd_command(0x01);

                                                lcd_string("Scan your ID");

                                }

                                if(key==12)

                                index++;

                }

                timer_on();

}

void main()

{

                col1=col2=col3=1;

    timer_on();

                lcd_ini();                                                                              //Place cursor to second position of first line

                lcd_string("Scan your ID");

                while(1)

                {

                                row1=row2=row3=row4=0;

                                if(col1==0)

                                {

                                                keypad();

                                }

                                if(print==1 && new_user==1)

                                {

                                                memory();

                                                print=0;

                                                new_user=0;

                                }

                                if(print==1 && recharge==1)

                                {

                                                recharge_acc();

                                                print=0;

                                                recharge=0;

                                }

                                if(current_byte==12)

                                {

                                                show();

                                }

                }

}