STEPS FOR RS-232 EXPERIMENT

1.Connect the RS-232 Cable for both system(Peer-to-Peer communication)

2.Log on the administrator from both system.

3.Open the terminal(Herculus software) in sender(system 1).

4.Then select the SERIEL for terminal window.

5.Then set the Portnumber,parity,baudrate and set mode as setup.

6.Open the terminal connection by using OPEN button.

7.Now it is ready to send the data to receiver(system 2). 

8.Open the turboc and run the receiver side program from receiver(system2).

9.Now receiver is ready to receive the data from sender.

10.Now sender can send the data to receiver by using terminal.

11.Then receiver will be receive the data from sender by using c program with turboc.

RECEIVER PROGRAM FOR RS-232

#include<stdio.h>
#include<conio.h>
#include<bios.h>
#define SETTINGS (_COM_9600 | _COM_CHR8 | _COM_NOPARITY |_COM_STOP1)
/* baud rate = 9600, 8 data bits, no parity bit, 1 stop bit */
void main(void)
{
unsigned in,out,status;
int port;
clrscr();
printf(“Select Port(Enter ‘0’ for COM1 and ‘1’ for COM2):”);
scanf(“%d”,&port);
printf(“Press ESC to exit”);
textcolor(GREEN);
cprintf(“\n\rData Received:\n”);
_bios_serialcom(_COM_INIT,port,SETTINGS);
for(;;)
{
status=_bios_serialcom(_COM_STATUS,port,0);
if (status & 512)
printf(“\n\t\a Overrun Error”);
if (status & 1024)
printf(“\n\t\a Parity Error”);
if (status & 2048)
printf(“\n\t\a Framing Error”);
if(status & (512|1024|2048)) /* if any error */
break;
if(status & 256) /* if data ready */
{
if((out=_bios_serialcom(_COM_RECEIVE,port,0) & 255)!=0)
putch(out);
}
if(kbhit()) /* if a keystroke is currently available */
{
in=getch(); /* get a character without echoing onto the screen */
if(in==27) /* if ESC */
break;
_bios_serialcom(_COM_SEND,port,in);
}
}
}

SLIDING WINDOW PROTOCOL PROGRAM

#include<stdio.h>
#include<conio.h>
#include<string.h>
int sx[10],rx[20];
int n=0,k=0,nk=0,sls=0,j=0,l=0,count=1,i=0;
void main()
{
clrscr();
printf("\n*****SLIDING WINDOW FLOW CONTROL PROTOCOL******\n");
printf("\nEnter the no of data:\n ");
scanf("%d",&n);
printf("\nenter the data at one by one:\n");
for(i=0;i<n;i++)
{
scanf("%d",&sx[i]);
}
printf("\nEnter the slide size:\n ");
scanf("%d",&sls);
printf("\n****The frame size is calculated [framesize=slidesize-1]****");
nk=sls-1;
printf("\nThe frame size is: %d \n",nk);
printf("\n\tSENDER \t\tRECEIVER\n\t*******\t\t*********\n");
for(i=0;i<n;i++)
{
rx[i]=sx[i];
k++;
printf("\t");
for(j=i;j<nk;j++)
printf("%d",sx[j]);
printf("\t\t");
for(l=0;l<k;l++)
printf("%d",rx[l]);
printf("\t\n");
if(i==count)
{
getch();
printf("\n\t   ACK%d is accered\n\n",count+1);
count+=2;
nk+=2;
}
getch();
}
printf("\n***The final zeros are consider as empty****");
getch();

}

SIMPLE CRC WITH COMMAND

#include<stdio.h>
#include<string.h>
#include<stdlib.h>
void calc();
void getd();
int i,j,n,g,a,arr[20],gen[20],b[20],q[20],x[20],check=0,s,ch=0;
main()
{
printf("\n\n\t ****** CYCLIC REDUNDANCY CHECK ****** ");
while(1)
{
printf("\n\n\tENTER THE NUMBER TO PERFORM THE OPERATION");
printf("\n\t~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n");
printf("\n\t1.SENDER SIDE CALCULATION\n\n\t2.RECEIVER SIDE CALCULATION\n\n\t3.EXIT");
printf("\n\n\tENTER YOUR CHOICE:");
scanf("%d",&ch);
switch(ch)
{
case 1:
/* SENDER SIDE CALCULATION */
printf("\n\t Transmitter side:");
getd(); //CALLING FUNCTION FOR GETTING DATA
printf("\n\t Enter no. of divisor bits to calculate: ");
scanf("%d",&g); //GET THE NO.OF BITS TO TRANSMIT
do //MUST INCLUDE THE FIRST BIT IS 1
{
printf("\n\t Enter the generator data: \n");
for(j=0;j<g;j++)
scanf("%d",&gen[j]);
}while(gen[0]!=1); //IF TRUE MEANS THE STARTING BIT OF THE DEVISER IS 0
printf("\n\t The divisor is:");
for(j=0;j<g;j++)
printf("%d",gen[j]);//PRINT THE DEVISER
a=n+(g-1); //CALCULATE THE TOTAL NO.OF BIT TO DERIVATION
printf("\n\t now the total[no.of data+(no.of diviser-1)] no.of bit is:%d",a);
printf("\n\t The transmitter side data is:");
for(i=0;i<j;++i)
arr[n+i]=0; //FILL UP THE 0 FOR REMAINING SPACE (EXTRA BIT)
for(i=0;i<a;++i)
printf("%d",arr[i]); //PRINT THE DATA WITH EXTRA BITS
calc(); // CALLING FUNCTION FOR CALCULATE THE CRC BITS
printf("\n\t THE RESULT IS:");
for(i=0;i<a;i++)
printf("%d",q[i]); //PRINT THE SENDER SIDE RESULT
break;
case 2:
/* RECEIVER SIDE CALCULATION*/
printf("\n\t Receiver side:");
//getd(); //CALLING FUNCTION FOR GET THE DATA FOR RECEIVER SIDE
for(i=0;i<n;++i)
arr[i] =q[i];
for(i=n,j=g-1;i<a,j<0;i++,j--)
arr[i]=q[j]; //ARRANGE THE CRC BITS INTO REVRSE ORDER (CALCULATE THE RECEIVER SIDE CRC BIT)
printf("\n\t The receiver side CRC bit is:");
for(i=0;i<g-1;++i)
printf("%d",q[i]); //PRINT RECEIVER SIDE CRC BIT
printf("\n\t The original data is:");
for(i=0;i<a;++i)
printf("%d",arr[i]);
printf("\n\t The receiver side data with crc is:");
for(i=0;i<a;++i)
printf("%d",arr[i]); //PRINT THE RECEIVER SIDE DATA WITH CRC BIT
calc(); //CALLING FUNCTION FOR CALCULATE OR IDENTIFY THE ERROR
printf("\n");
i=0;
while(i<a)
{
if(q[i]==0)
check=0;
else
check=1;
i++;
}
printf("\n\n Result of CRC Error detection is: ");
if(check==0)
printf("\n\t Data is accepted successfully!");
else
printf("\n Resend the data again!");
break;
case 3:
exit(0);
break;
}
}

}
void calc()
{
for(i=0;i<n;++i)
q[i]= arr[i]; //TAKE THE COPY TO OUR ORIGINAL DATA
for(i=0;i<n;++i)
{
if(arr[i]==0)//IF TRUE MEANS THE ORIGINAL DATA OR CURRRENT STAGE RESULT FIRST BIT IS 0
{
printf("\n\t The first bit is o:");
for(j=i;j<g+i;++j)
arr[j] = arr[j]^0; //PERFORM THE EX-OR OPERATION BY OOOO
printf("\n\t The answer is :\t");
for(j=i;j<g+i;++j)
printf(" %d",arr[j]);//PRINT THE CURRENT STAGE RESULT
}
else //IF TRUE MEANS THE ORIGINAL DATA OR CURRRENT STAGE RESULT FIRST BIT IS 0
{
arr[i] = arr[i]^gen[0]; //} THE PERFORMENCE OF THE EX- OR OPERATION
arr[i+1]=arr[i+1]^gen[1]; //} IN THE DATA BY USING THE DIVISER BITS
arr[i+2]=arr[i+2]^gen[2]; //}
arr[i+3]=arr[i+3]^gen[3]; //}
printf("\n\n\t The answer is :\t");
for(j=i;j<g+i;++j)
printf(" %d",arr[j]); //PRINT THE CURRENT STAGE RESULT
}
}
printf("\n\t The CRC bit is :");
for(i=n;i<a;++i)
printf("%d",arr[i]); //PRINT THE FINAL RESULT OF AFTER THE CRC CALCULATION
for(i=0;i<g-1;++i)
x[i]=arr[i];
s=n+a;
for(i=n;i<s;i++)
q[i]=arr[i];
}
void getd()
{
printf("\n\t Enter no. of data bits: ");
scanf("%d",&n); //GET THE DATA SIZE
printf("\n\t Enter the data bits:\n ");
for(i=0;i<n;i++)
scanf("%d",&arr[i]); //GET THE ORIGINAL DATA
printf("\n\t The given data is:");
for(i=0;i<n;++i)
printf("%d",arr[i]); //PRINT THE DATA
}

THE SIMPLE HAMMING CODE

/* SIMPLE HAMMING CODE*/
#include<stdio.h>
#include<math.h>
#include<ctype.h>
void assign(void);
void compare(void);
void rr1(void);
void rr2(void);
void rr4(void);
void rr8(void);
void print(void);
int i,ch=0;
int h[12],e[12],f[8];
int r1,r2,r4,r8;

void main()
{
printf("\n\n\tHAMMING CODE\n");
while(1)
{
  printf("\n1.transmitter side.\t 2.receiver side.\t3.exit\n");
  scanf("%d",&ch);  //GET THE INPUT OF CHOICE
  switch(ch)
  {
   case 1:
    printf("\n hamming code at transmittr side\n");  //TRANSMITTER
    printf("enter the 7 bit data:\n");
    for(i=7;i>=1;i--)
      scanf("%d",&f[i]);  //GET THE 7 BIT DATA
    assign();                              //GENERATE THE HAMMING CODE
    printf("HAMMING CODE\n");
    print();                 //PRINT THE RESULT
    rr1();              
    rr2();
    rr4();
    rr8();
    break;
   case 2:
     printf("\n hamming code at receiver side\n");  //RECEIVER
    printf("enter the receiver side data\n");
    for(i=11;i>=1;i--)
      scanf("%d",&e[i]);      //GET THE RECEIVER SIDE DATA
    printf("\n HAMMING CODE IN RECEIVER SIDE\n");
     for(i=11;i>=1;i--)
      printf("%d",e[i]);  //PRINT THE HAMMING CODE
    compare();   //COMPARE THE RECEIVER HAMMING CODE AND THE RESULT OF                                                                                                                           //R1,R2,R4,R8
    break;
   default:
     exit(1);
     break;
  }
}

}
void print() //DEFINITION OF PRINT() FUNCTION
{
 for(i=11;i>=1;i--)
  printf("%d",h[i]);//PRINT THE VALUE
}
void assign()//DEFINITION OF ASSIGN() FUNCTION
{                       //TO GENERATE THE 11 DIGIT HAMMING CODE
   h[11]=f[7];
   h[10]=f[6];
   h[9]=f[5];
   h[8]=0;
   h[7]=f[4];
   h[6]=f[3];
   h[5]=f[2];
   h[4]=0;
   h[3]=f[1];
   h[2]=0;
   h[1]=0;

}
void rr1() //DEFINITION OF RR1() FUNCTION
{
  printf("\n r1\n");

   r1=h[1]+h[3]+h[5]+h[7]+h[9]+h[11]; //ADD THE POSITION 1,3,5,7,9,11
  if((r1==6) || (r1==4) || (r1==2) || (r1==0))  //IF IT IS EVEN
    h[1]=0;                                            //SET 0
  else
    h[1]=1;             //OTHERWISE SET 1
  print();  //CALLING FOR PRINT() FUNCTION
}
void rr2()   //DEFINITION OF RR2()
{
  printf("\n r2\n");
  r2=h[2]+h[3]+h[6]+h[7]+h[10]+h[11];  //ADD THE POSITION 2,3,6,7,10,11
  if((r2==6) || (r2==4) || (r2==2) ||(r2==0))  //IF IT IS EVEN SET 0
    h[2]=0;
  else
    h[2]=1;            //OTHERWISE SET 1
  print();
}
void rr4()         //DEFINITION OF RR4()
{
  printf("\n r4\n");
  r4=h[4]+h[5]+h[6]+h[7];   //ADD THE POSITION 4,5,6,7
  if((r4==2) || (r4==0)|| (r4==4))  //IF IT IS EVEN SET 0
    h[4]=0;
  else                                 //OTHERWISE SET 1
    h[4]=1;
  print();
}
void rr8()  //DEFINITION OF RR8()
{
  printf("\n r8\n");
  r8=h[8]+h[9]+h[10]+h[11];  //ADD THE POSITION 8,9,10,11
  if((r8==4) || (r8==2) || (r8==0))  //IF IT IS EVEN SET 0
    h[8]=0;
  else         /OTHERWISE SET 1
    h[8]=1;
  print();  //CALLING THE PRINT();
}
void compare()  //DEFINITION OF COMPARE()
{
   int b=0;
   for(i=11;i>=1;i--)
     if(h[i]!=e[i])  
       b=i;
   if(b==0)
     printf("\n there is no error in receiver side");
   else
     printf("error is present at %dth bit",b);
}