#include<avr/io.h>
void main()
{
DDRA=0xFF;
while(1)
{
PORTA=~PORTA;
}
}
Hex Code
|
Command to LCD Instruction Register
|
1
|
Clear screen display
|
2
|
Return home
|
4
|
Decrement cursor
|
6
|
Increment cursor
|
E
|
Display ON, Cursor ON
|
80
|
Force the cursor to the beginning of the 1st line
|
C0
|
Force cursor to the beginning of the 2nd line
|
38
|
Use 2 lines and 5x7 matrix
|
Pin
|
Symbol
|
Description
| |
1
|
VSS
|
Ground
|
0 V
|
2
|
VCC
|
Main power supply
|
+5 V
|
3
|
VEE
|
Power supply to control contrast
|
Contrast adjustment by providing a variable resistor through VCC
|
4
|
RS
|
Register Select
|
RS=0 to select Command Register
RS=1 to select Data Register
|
5
|
R/W
|
Read/write
|
R/W=0 to write to the register
R/W=1 to read from the register
|
6
|
EN
|
Enable
|
A high to low pulse (minimum 450ns wide) is given when data is sent to data pins
|
7
|
DB0
|
To display letters or numbers, their ASCII codes are sent to data pins (with RS=1). Also instruction command codes are sent to these pins.
| |
8
|
DB1
| ||
9
|
DB2
| ||
10
|
DB3
|
8-bit data pins
| |
11
|
DB4
| ||
12
|
DB5
| ||
13
|
DB6
| ||
14
|
DB7
| ||
15
|
Led+
|
Backlight VCC
|
+5 V
|
16
|
Led-
|
Backlight Ground
|
0 V
|
#include<reg51.h>
#define cmdport P3
#define dataport P2
#define q 100
sbit rs = cmdport^0; //register select pin
sbit rw = cmdport^1; // read write pin
sbit e = cmdport^6; //enable pin
void delay(unsigned int msec) // Function to provide time delay in msec.
{
int i,j ;
for(i=0;i<msec;i++)
for(j=0;j<1275;j++);
}
void lcdcmd(unsigned char item) //Function to send command to LCD
{
dataport = item;
rs= 0;
rw=0;
e=1;
delay(1);
e=0;
}
void lcddata(unsigned char item) //Function to send data to LCD
{
dataport = item;
rs= 1;
rw=0;
e=1;
delay(1);
e=0;
}
void main()
{
lcdcmd(0x38); // for using 8-bit 2 row mode of LCD
delay(100);
lcdcmd(0x0E); // turn display ON for cursor blinking
delay(100);
lcdcmd(0x01); //clear screen
delay(100);
lcdcmd(0x06); //display ON
delay(100);
lcdcmd(0x86); // bring cursor to position 6 of line 1
delay(100);
lcddata('A');
}
#include<reg51.h>
#define port P1
#define dataport P2
#define key P0
#define sec 100
sbit rs = port^0;
sbit rw = port^1;
sbit en = port^2;
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;
sbit lock_output=P0^7;
int check=0;
int digit[4]={0,0,0,0};
int dig_input[4]={0,0,0,0};
int dig_input_recheck[4]={0,0,0,0};
int i,k;
void delay(unsigned int msec) // Time delay function
{
int i,j ;
for(i=0;i<msec;i++)
for(j=0;j<1275;j++);
}
void lcd_cmd(unsigned char item) // Function to send command to LCD
{
dataport = item;
rs= 0;
rw=0;
en=1;
delay(1);
en=0;
return;
}
void lcd_data(unsigned char item) // Function to send data to LCD
{
dataport = item;
rs= 1;
rw=0;
en=1;
delay(1);
en=0;
return;
}
void lcd_data_string(unsigned char *str) // Function to send data to string
{
int i=0;
while(str[i]!='\0')
{
lcd_data(str[i]);
i++;
//delay(10);
}
return;
}
void lcd(unsigned char str[10])
{
lcd_cmd(0x38);
lcd_cmd(0x0e);
lcd_data_string(str);
}
void ans()
{
if(check>3)
{
lcd_cmd(0x01);
lcd_cmd(0x82);
lcd_data_string(" LOCK OPEN");
lock_output=1;
delay(300);
while(1);
}
else
{
lcd_cmd(0x01);
lcd_cmd(0x82);
lcd_data_string(" WRONG PASSWORD");
lock_output=0;
delay(300);
}
}
void code_check() // Function to check password
{
if(i<=3 )
{
switch((i+1))
{
case 1: {
if(dig_input[0]==digit[0])
{
check=check+1;
}
break;
}
case 2: {
if(dig_input[1]==digit[1])
{
check=check+1;
}
break;
}
case 3: {
if(dig_input[2]==digit[2])
{
check=check+1;
}
break;
}
case 4: {
if(dig_input[3]==digit[3])
{
check=check+1;
}
break;
}
}
}
delay(10);
if(i==3)
{
ans();
}
}
void display(int a) //Display function
{
switch(a)
{
case 1:{
lcd_data('*');
delay(100);
digit[i]=1;
code_check();
break;
}
case 2:{
lcd_data('*');
delay(100);
digit[i]=2;
code_check();
break;
}
case 3:{
lcd_data('*');
delay(100);
digit[i]=3;
code_check();
break;
}
case 4:{
lcd_data('*');
delay(100);
digit[i]=4;
code_check();
break;
}
case 5:{
lcd_data('*');
delay(100);
digit[i]=5;
code_check();
break;
}
case 6:{
lcd_data('*');
delay(100);
digit[i]=6;
code_check();
break;
}
case 7:{
lcd_data('*');
delay(100);
digit[i]=7;
code_check();
break;
}
case 8:{
lcd_data('*');
delay(100);
digit[i]=8;
code_check();
break;
}
case 9:{
lcd_data('*');
delay(100);
digit[i]=9;
code_check();
break;
}
case 0:{
lcd_data('*');
delay(100);
digit[i]=0;
code_check();
break;
}
}
}
void 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)
{
row4=1;
}
}
void 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;
}
void 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)
{
row4=1;
}
}
void check_password_col1()
{
row1=row2=row3=row4=1;
row1=0;
if(col1==0)
dig_input[k]=1;
row1=1;
row2=0;
if(col1==0)
dig_input[k]=4;
row2=1;
row3=0;
if(col1==0)
dig_input[k]=7;
row3=1;
row4=0;
if(col1==0)
{
row4=1;
}
}
void check_password_col2()
{
row1=row2=row3=row4=1;
row1=0;
if(col2==0)
dig_input[k]=2;
row1=1;
row2=0;
if(col2==0)
dig_input[k]=5;
row2=1;
row3=0;
if(col2==0)
dig_input[k]=8;
row3=1;
row4=0;
if(col2==0)
{
dig_input[k]=0;
row4=1;
}
}
void check_password_col3()
{
row1=row2=row3=row4=1;
row1=0;
if(col3==0)
dig_input[k]=3;
row1=1;
row2=0;
if(col3==0)
dig_input[k]=6;
row2=1;
row3=0;
if(col3==0)
dig_input[k]=9;
row3=1;
row4=0;
if(col3==0)
{
row4=1;
}
}
void pass_set()
{
row1=row2=row3=row4=0;
while(col1==1 && col2==1 && col3==1);
for(i=0;i<4;i++)
{
k=i;
delay(50);
lcd_cmd(0xc4+i);
delay(100);
row1=row2=row3=row4=0;
while(col1==1 && col2==1 && col3==1);
row1=row2=row3=row4=0;
if(col1==0)
check_password_col1();
else
if(col2==0)
check_password_col2();
else
if(col3==0)
check_password_col3();
lcd_data('*');
delay(50);
}
}
void main()
{
int e,j=0,count=1;
col1=col2=col3=1;
//FOR PASSWoRD INPUT
do
{
lcd_cmd(0x01); //Clear LCD screen
lcd_cmd(0x81);
lcd("ENTER PASSWORD:");
pass_set();
for(e=0;e<4;e++)
dig_input_recheck[e]=dig_input[e];
lcd_cmd(0x01);
lcd("CONFIRM PASSWORD:");
pass_set();
for(e=0;e<4;e++)
{
if(dig_input_recheck[e]==dig_input[e])
j++;
}
if(j<4)
{
lcd_cmd(0x01);
lcd_cmd(0x85);
lcd("PASSWORD");
lcd_cmd(0xC2);
lcd("NOT MATCH");
delay(300);
}
}
while(j<4);
while(count<4) //Code input and check
{
lcd_cmd(0x01);
lock_output=0;
lcd_cmd(0x82);
lcd("ENTER PASSWORD");
check=0;
row1=row2=row3=row4=0;
while(col1==1 && col2==1 && col3==1);
for(i=0;i<4;i++)
{
delay(100);
lcd_cmd(0xc4+i);
row1=row2=row3=row4=0;
while(col1==1 && col2==1 && col3==1);
row1=row2=row3=row4=0;
if(col1==0)
check_col1();
else
if(col2==0)
check_col2();
else
if(col3==0)
check_col3();
}
count++;
delay(1);
}
if(count==4)
{
lcd_cmd(0x01);
lcd_cmd(0x86);
lcd("SORRY");
lcd_cmd(0xc1);
lcd("NO MORE TRIALS");
while(1);
}
}