Ultrasonic Distance Finder By Using 89c51

Ultrasonic Distance Finder By Using  89c51

                                                       Bismiallah Hirahman Niraheem 

As you see below there are two code one is main code and another is a external function code and this is for serial transmit ...when main code call this function then serial transmission is occur .

Important thing is that i use cyrstal oscillator of   11.0592 Mhz    for serial communication ...12Mhz oscillator not worked .

You can Also DOWNLOAD  hex File from Link   given in the end of this page

 

 

Main Code :

#include <AT89X51.h>

#include <stdio.h>

extern void SerialTx(signed int);

sbit Trigger=P1^0;

sbit Eco=P1^1;

sbit Led=P1^2;

void main (void)

 {

    int c;

    unsigned int t;

    float s;

    float f;

    SerialTx(-3);      // External Function Call  ( board rate 9600 )

TMOD=0x21;     //use Timer 1 in mode 2 and Timer 0 in mode 1 ,  {timer 0 } start and stop from externally

    TI=1;

    Trigger=0;                          // Make trigger as output

    Eco=1;                              // Make Eco as Input

     

    while(1)

    {

      

          

         TH0=0xD8;                     // initialized by  38ms  for Eco check

         TL0=0xF0;

        Trigger=1;

        for(c=0;c<1;c++);               // From calculation this is Aprox 14 usec delay

        Trigger=0;

       

        while(Eco==0){ ; }                 //  Wait until eco = 0

        TR0=1;

        while(Eco==1)                       //  Wait until eco = 1

        {

            if(TF0 == 1)

            {

                 printf("Object is out of range...........\n ");     

                TF0 = 0;

                break;

            }

        }   

        TR0 = 0;

        t = TH0;

        t = t<<8;

        t = t+TL0;

        t = t - 0xD8F0;

        Led=~Led;

         s=.0165F*t;                       //formula for coverting into centimeter

        f=s*.0300F;                            //formula for converting into foots

   

   

        printf("Timer Exact Value = %u \n\n\n" ,t);                                              // Exact value

        printf("Counted Distance Value = %f cm \n\n\n " ,s);

        printf("Counted Distance Value = %f  Foot \n\n\n " ,f);                             // Calculated Distance

                        

         

   

}

  

}

          External Function Serial Transmit   SerialTx : 

 

#include <reg51.h>
#include <stdio.h>
void SerialTx(signed int );
void SerialTx(signed int a)
{

TH1=a; //9600 baud rate  FD = -3
SCON=0x50;
TR1=1;   
}

Download  Hex File Click Here  

Electronics Lab Created By Muhammad Irfan