exp_6_7_8_9

// SQUARE_WAVE_KEIL_8051

#include <reg51.h>
sbit pin = P1^0;
main()
{
      P1 = 0x00;
      TMOD = 0x09;
loop:TL0 = 0xAF;
      TH0 = 0x3C;
       pin = 1;
       TR0 = 1;
       while(TF0 == 0)  {}

       TL0 = 0xAF;
       TH0 = 0x3C;
       pin = 0;
      while(TF0 == 0)  {}
  goto loop;
}
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// LED interfacing

#include <reg51.h>

sbit LED = P1^0;

void delay(unsigned int y){
    unsigned int i, j;
    for(i = 0; i < y; i++) {
        for(j = 0; j < 1275; j++) {
        }
    }
}
void main(){
    while(1) {
        delay(100);
        LED = 0;
        delay(100);
        LED = 1;
    }
}
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// DC Motor interfacing

#include<reg51.h>
#include<stdio.h>

void delay(void);

sbit motor_pin_1 = P2^0;
sbit motor_pin_2 = P2^1;

void main()
{
  do
  {
\    motor_pin_1 = 1;
    motor_pin_2 = 0; //Rotates Motor Anit Clockwise
    delay();
    motor_pin_1 = 1;
    motor_pin_2 = 1; //Stops Motor
    delay();
    motor_pin_1 = 0;
    motor_pin_2 = 1; //Rotates Motor Clockwise
    delay();
    motor_pin_1 = 0;
    motor_pin_2 = 0; //Stops Motor
    delay();
  }while(1);
}

void delay()
{
  int i,j;
  for(i=0;i<1000;i++){
    for(j=0;j<1000;j++){
    }
}
}

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// LCD Interfacing

#include<reg51.h>
#define display_port P2
sbit rs = P3^2;
sbit rw = P3^3;
sbit e =  P3^4;

void msdelay(unsigned int time)
{
    unsigned i,j ;
    for(i=0;i<time;i++);
    for(j=0;j<1275;j++);
}
void lcd_cmd(unsigned char command)
{
    display_port = command;
    rs= 0;
    rw=0;
    e=1;
    msdelay(1);
    e=0;
}
void lcd_data(unsigned char disp_data)
{
    display_port = disp_data;
    rs= 1;
    rw=0;
    e=1;
    msdelay(1);
    e=0;
}
void lcd_init()
{
    lcd_cmd(0x38);
    msdelay(10);
    lcd_cmd(0x0F);
    msdelay(10);
    lcd_cmd(0x01);
    msdelay(10);
    lcd_cmd(0x81);
    msdelay(10);
}
void main()
{
    unsigned char a[8]="TESGING";
    int l=0;
    lcd_init();
    while(a[l] != '\0')
    {
        lcd_data(a[l]);
        l++;
        msdelay(50);
    }
}

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// Matrix Keyboard

#include<reg51.h>

#define display_port P2
sbit rs = P3^2;
sbit rw = P3^3;
sbit e =  P3^4;
sbit C4 = P1^0;
sbit C3 = P1^1;
sbit C2 = P1^2;
sbit C1 = P1^3;
sbit R4 = P1^4;
sbit R3 = P1^5;
sbit R2 = P1^6;
sbit R1 = P1^7;


void msdelay(unsigned int time)
{
    unsigned i,j ;
    for(i=0;i<time;i++)
    for(j=0;j<1275;j++);
}
void lcd_cmd(unsigned char command)
{
    display_port = command;
    rs= 0;
    rw=0;
    e=1;
    msdelay(1);
    e=0;
}
void lcd_data(unsigned char disp_data)
{
    display_port = disp_data;
    rs= 1;
    rw=0;
    e=1;
    msdelay(1);
    e=0;
}
void lcd_init()
{
    lcd_cmd(0x38);
    msdelay(10);
    lcd_cmd(0x0F);
    msdelay(10);
    lcd_cmd(0x01);
    msdelay(10);
    lcd_cmd(0x81);
    msdelay(10);
}
void row_finder1()
{
R1=R2=R3=R4=1;
C1=C2=C3=C4=0;
if(R1==0)
lcd_data('1');
if(R2==0)
lcd_data('4');
if(R3==0)
lcd_data('7');
if(R4==0)
lcd_data('*');
}
void row_finder2()
{
R1=R2=R3=R4=1;
C1=C2=C3=C4=0;
if(R1==0)
lcd_data('2');
if(R2==0)
lcd_data('5');
if(R3==0)
lcd_data('8');
if(R4==0)
lcd_data('0');
}
void row_finder3() //Function for finding the row for column 3
{
R1=R2=R3=R4=1;
C1=C2=C3=C4=0;
if(R1==0)
lcd_data('3');
if(R2==0)
lcd_data('6');
if(R3==0)
lcd_data('9');
if(R4==0)
lcd_data('#');
}
void row_finder4() //Function for finding the row for column 4
{
R1=R2=R3=R4=1;
C1=C2=C3=C4=0;
if(R1==0)
lcd_data('A');
if(R2==0)
lcd_data('B');
if(R3==0)
lcd_data('C');
if(R4==0)
lcd_data('D');
}

void main()
{
    lcd_init();
    while(1)
    {
        msdelay(30);
        C1=C2=C3=C4=1;
          R1=R2=R3=R4=0;
          if(C1==0)
          row_finder1();
          else if(C2==0)
           row_finder2();
           else if(C3==0)
        row_finder3();
        else if(C4==0)
        row_finder4();
    }
}

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