This document contains C code for controlling a robot using an AT89S52 microcontroller and LCD display. It defines functions for initializing and sending commands/data to the LCD. The main function initializes ports and the LCD, displays an intro message, then enters a loop to check the states of sensor inputs. Depending on the sensor states, it controls motors and displays messages on the LCD like "FORWARD", "REVERSE", "TURNING RIGHT", "TURNING LEFT", or "STOP" if no signals.

1. #include<reg51.h>
sbit s1=(P0^1);
sbit s2=(P0^2);
sbit s3=(P0^3);
sbit s4=(P0^4);
sbit d1=(P1^1);
sbit d2=(P1^2);
sbit d3=(P1^3);
sbit d4=(P1^4);
sbit en=(P1^5);
#define cmdport P3
#define dataport P2
#define q 10
#define O 1
sbit rs=cmdport^2;//register select pin
sbit rw=cmdport^1;//read write pin
sbit e=cmdport^0;//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<550;j++);
}
void lcdcmd(unsigned char msg)//Function to send command to LCD
{
dataport=msg;
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;
}
lcddat(unsigned char*item)//function to send string to LCD
{
int x;
for(x=0;item[x]!=0;x++)
{
lcddata(item[x]);
}
}
void main()
{
P1=0x00;
P2=0x00;
P3=0x00;
delay(100);
lcdcmd(0x38);
delay(q);
lcdcmd(0x01);
delay(q);
lcdcmd(0x0C);
delay(q);
lcdcmd(0x80);
delay(q);
lcddat("Wireless Gesture");

2. lcdcmd(0xC0);
delay(q);
lcddat("Controlled Robot");
delay(700);
lcdcmd(0x01);
delay(q);
lcdcmd(0x81);
delay(q);
lcddat("Using AT89S52");
delay(q);
lcdcmd(0xC0);
delay(q);
lcddat("Micro-controller");
delay(700);
lcdcmd(0x38);
delay(q);
lcdcmd(0x01);
delay(q);
lcdcmd(0x0C);
delay(q);
lcdcmd(0x86);
delay(q);
lcddat("By:");
delay(q);
lcdcmd(0xC2);
delay(q);
lcddat("Group No.8");
delay(650);
while(1)
{
if(!s1 & !s2 & s3 & !s4)
{
en=1;
d1=1,d3=1;
d2=0,d4=0;
lcdcmd(0x38);
delay(q);
en=0;
lcdcmd(0x01);
delay(q);
en=1;
lcdcmd(0x0C);
delay(q);
lcdcmd(0x80);
en=0;
delay(q);
lcddat("Receiving Signal.");
en=1;
delay(q);
lcdcmd(0xC0);
delay(q);
en=0;
lcdcmd(0x0C);
delay(q);
en=1;
lcddat("GOING FORWARD");
delay(40);
en=0;
}
if(!s1 & !s2 & !s3 & s4)
{
en=1;
d1=0,d4=0;
d2=1,d3=1;

3. lcdcmd(0x38);
delay(q);
en=0;
lcdcmd(0x01);
delay(q);
en=1;
lcdcmd(0x0C);
delay(q);
lcdcmd(0x80);
delay(q);
en=0;
lcddat("Receiving Signal.");
delay(q);
en=1;
lcdcmd(0xC0);
delay(q);
en=0;
lcdcmd(0x0C);
delay(q);
en=1;
lcddat("GOING REVERSE");
delay(40);
en=0;
}
if(!s1 & s2 & !s3 & !s4)
{
en=1;
d1=0,d3=0;
d2=1,d4=1;
lcdcmd(0X38);
delay(q);
en=0;
lcdcmd(0x01);
en=1;
delay(5);
en=0;
lcdcmd(0x0C);
en=1;
delay(5);
en=0;
lcdcmd(0x80);
en=1;
delay(q);
en=1;
delay(5);
en=0;
lcddat("Receiving Signal.");
delay(q);
lcdcmd(0xC0);
delay(q);
lcdcmd(0x0C);
delay(q);
lcddat("TURNING RIGHT");
en=1;
delay(5);
en=0;
delay(2);
en=1;
delay(5);
en=0;
en=1;
delay(5);
en=0;
delay(40);

4. }
if(s1 & !s2 & !s3 & !s4)
{
en=1;
d1=1,d4=1;
d2=0,d3=0;
lcdcmd(0x38);
delay(q);
en=0;
lcdcmd(0x01);
en=1;
delay(5);
en=0;
lcdcmd(0x0C);
en=1;
delay(5);
en=0;
lcdcmd(0x80);
en=1;
delay(q);
en=1;
delay(5);
en=0;
lcddat("Receiving Signal.");
delay(q);
lcdcmd(0xC0);
delay(q);
lcdcmd(0x0c);
delay(q);
lcddat("TURNING LEFT");
en=1;
delay(5);
en=0;
delay(2);
en=1;
delay(5);
en=0;
en=1;
delay(5);
en=0;
delay(40);
}
if(!s1 & !s2 & !s3 & !s4)
{
en=0;
d1=0;
d2=0;
d3=0;
d4=0;
lcdcmd(0x38);
delay(q);
lcdcmd(0x01);
delay(q);
lcdcmd(0x0C);
delay(q);
lcdcmd(0x80);
delay(q);
lcddat("No Signal");
delay(q);
lcdcmd(0xC0);
delay(q);
lcdcmd(0x0C);
delay(q);
lcddat("STOP");

5. delay(40);
}

6. delay(40);
}