#include <pic.h>

/********************************************************
*  
* Program Title:     Flash D0 with Initialization and Delay Written in C 
*
* Program File Name: Lecture_11A.c  
*
* Microprocessors B 17.384
*
* Spring 2009
*
* Dohn Bowden
*
* 04/18/2009  
*
********************************************************/




/********************************************************
* Function: main
*
* Description:  D0 on PICkit 1 will Flash on and off
*
* Notes:
*
* RA4 - Positive LED Connection for D0
* RA5 - Negative LED Connection for D0
*
* Returns:  This routine contains an infinite loop
*
********************************************************/


/* Configuration Word */

__CONFIG(INTIO & WDTDIS & PWRTEN & MCLRDIS & UNPROTECT \
  & UNPROTECT & BORDIS & IESODIS & FCMDIS);
  
void PORTA_init(void);

void delay_routine(void);

main()
{

	PORTA_init();

    	while(1 == 1)               	//  Loop Forever
    	{
		
		delay_routine();
		NOP();
        	RA4 = 1;                //  D0 LED On by making RA4 high

		delay_routine();

        	RA4 = 0;                //  D0 LED Off by making RA4 low

    	}  // *** END OF While (1 == 1) LOOP
 
	return;
 
}

/******** END OF main ROUTINE ***************************/

/********************************************************
* Function: PORT_init
*
* Description:  Initializes PORTA to a known condition
*
* Notes:    None
*
* Returns:  None
*
*
********************************************************/
void PORTA_init(void)
{
	PORTA = 0;                  	//  All PORTA Pins are low
    	CMCON0 = 7;                 	//  Turn off Comparators
    	ANSEL = 0;                  	//  Turn off ADC
	TRISA = 0b001111;		//  RA4 and 5 are outputs; RA0,1,2, and 3 are input

	return;

}
/******** END OF PORTA_init ****************************/

/********************************************************
* Function: delay_routine
*
* Description:  Causes a delay in program execution
*
* Notes:
*
* Delay was determined through trial and error
*
* Returns:  None
*
********************************************************/
void delay_routine(void)
{
	int i, j;
		
	for (i = 0; i < 255; i++)  
    		for (j = 0; j < 255; j++);
		
	return;

}
/******** END OF delay_routine *************************/