/***********************************************************************
TARGET MICROCONTROLLER  :  PIC16F877A
COMPILER                :  CCS-C COMPILER
PROGRAM                 : TO DISLAY THE CHECKSUM( 8 BIT ADDITION OF ARRAY VALUE)IN  PORTC IN ARRAY WE HAVE THE VALUE OF 0X01,0X02,0X03,0X04,0X05,0X06,0X07,0X08,0X09
DISPLAY  THE SUM OF ARRAY VALUE IN PORTC(0X2D)  
***********************************************************************/
#include <16F877a.h>
#include <math.h>                			/*Header file*/
#fuses HS, NOWDT, NOPROTECT
#use delay(clock=6000000)

#BYTE TRISC = 0x87
#BYTE PORTC = 0x07
int8 a[] ={0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09},n=0,k=0; /* look up table*/
#Zero_Ram                 		 /* starting address of program(0000h)*/
void checksum(void);       		/* prototype declaration*/
void display(void);
void main ()              			/* start the main program*/
{
          TRISC  = 0x00;     		 /* PORTC as output*/
          PORTC=0xff;
          checksum();      			/* call the checksum function*/
          while(1);
}
void checksum(void)       		 /*function definition*/
{
  	int j;
  	for(j=0;j<9;j++)
   	{
     		n=a[j];
   		k=k+n;            		  /* add each array value and store in variable k*/
		delay_ms(100);
   	}
   	PORTC=~k;       	              /*Display the result in PORTC*/
}