how to add the two numbers in this controller

Pointers

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


unsigned char xdata *addend;
unsigned char xdata *augend;
unsigned int  xdata sum;
void main()
{
   addend = 0x1234;
   augend = 0x1235;

   sum = *addend + *augend;
}

_at_

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


unsigned char xdata addend _at_ 0x1234;
unsigned char xdata augend _at_ 0x1235;
unsigned int  xdata sum;
void main()
{
   sum = addend + augend;
}

XBYTE

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


unsigned int  xdata sum;
void main()
{
   sum = XBYTE[0x1234] + XBYTE[0x1235];
}

The Manual is your Friend

Pointers

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


unsigned char xdata *addend;
unsigned char xdata *augend;
unsigned int  xdata sum;
void main()
{
   addend = 0x1234;
   augend = 0x1235;

   sum = *addend + *augend;
}

_at_

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


unsigned char xdata addend _at_ 0x1234;
unsigned char xdata augend _at_ 0x1235;
unsigned int  xdata sum;
void main()
{
   sum = addend + augend;
}

XBYTE

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


unsigned int  xdata sum;
void main()
{
   sum = XBYTE[0x1234] + XBYTE[0x1235];
}

The Manual is your Friend

thank you sir

sir

i want some details about Serial COM port. how the data get it from the Serial port. So what is the procedure for that type of program

Have you looked for manuals and sample programs for the processor of choice?

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