Modules: 

// First Module, Main Module  (Main.c)

#include <Reg935.h> 					
#include <stdio.h>
#include <String.h>
#include <intrins.h>

#include "variables.h"

Void Main (void) 
{
unsigned char data Sec, Min, Hr, Day; 
unsigned char code Zero [] = {0x03, 0x61, 0x11, 0x03};
unsigned int Value = 0;
unsigned char dat;

}
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// End of first module
/**************************************/

//Second module
//Calc.c 

#include <Reg935.h> 					
#include <stdio.h>
#include <String.h>
#include <intrins.h>

#include “variables.h” 
Void Main_Calc (void)
{

}
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// End of second module

/**************************************/

Header: 

Variables.h 	(Name of  Header)


//To be used in Main.c  delete this line for globals 
extern unsigned char data Sec, Min, Hr, Day;
//To be used in Calc.c  delete this line for globals
extern unsigned char code Zero [] = {0x03, 0x61, 0x11, 0x03};
extern unsigned int Value = 0;
extern unsigned char dat;