dips.c

AT91所有开发板的资料 AT91所有开发板的资料

/****************************************************************
 *
 * ARM Strategic Support Group
 * 
 ****************************************************************/

/****************************************************************
 *
 *	Module		: dips.c
 *	Description	: Polls the DIP switch and displays the value in
 *				  in hex.
 *
 *  Tool Chain	: ARM Developer Suite 1.0
 *	Platform	: Evaluator7T
 * 	Status		: Complete
 * 	History		: 
 *
 *					2000-03-22 Andrew N. Sloss
 *					- implemented
 *				
 *	Notes		:
 *
 *				This program never end the user has to break in
 *				using the debugger.
 *
 ****************************************************************/

/****************************************************************
 * IMPORT
 ****************************************************************/

#include "segment.h"

/****************************************************************
 * MACROS
 ****************************************************************/

// -- base value for registers on the Evaluator7T ..............

#define SYSCFG			0x03ff0000	

// -- look up the Samsung User's Manual for more information....

#define IOPMOD          ((volatile unsigned *)(SYSCFG+0x5000))
#define IOPDATA         ((volatile unsigned *)(SYSCFG+0x5008))

#define SWITCH_MASK		(0xf)
#define FOREVER 		(1)

#define	angel_SWI		0x123456
__swi (angel_SWI) void _Exit(unsigned op, unsigned except);
#define Exit() 			_Exit(0x18,0x20026) 

__swi (angel_SWI) void _WriteC(unsigned op, const char *c);
#define WriteC(c) 		_WriteC (0x3,c)



/****************************************************************
 * DATATYPES
 ****************************************************************/

// -- segment display ..........................................

static unsigned int numeric_display [16] = 
{
	DISP_0,
	DISP_1,
	DISP_2,
	DISP_3,
	DISP_4,
	DISP_5,
	DISP_6,
	DISP_7,
	DISP_8,
	DISP_9,
	DISP_A,
	DISP_B,
	DISP_C,
	DISP_D,
	DISP_E,
	DISP_F
};	

/****************************************************************
 * ROUTINES
 ****************************************************************/


/* -- dips_delay ------------------------------------------------
 * 
 * Description	: produces a particular time delay. 
 *
 * Parameters	: int d - depth
 * Return		: none...
 * Notes		: 
 *
 */

void dips_delay (int w)
{
int y;

	for ( y=0; y<=w; y++) {};	
}	

/* -- dips_setsegment -------------------------------------------
 * 
 * Description	: outputs a value on the segment display 
 *
 * Parameters	: unsigned d - new display value
 * Return		: none...
 * Notes		: 
 *
 */
 
void dips_setsegment (unsigned d)
{
		*IOPDATA 	&= ~SEG_MASK;
		*IOPDATA 	|= d;	
}

/* -- dips_init  ------------------------------------------------
 * 
 * Description	: setups the segment display  
 *
 * Parameters	: none...
 * Return		: none...
 * Notes		: 
 *
 */
 
void dips_init (void)
{
	*IOPMOD 	|= SEG_MASK;
	*IOPDATA 	|= SEG_MASK;
}

/* -- dips_read ------------------------------------------------
 * 
 * Description	: reads the DIP switch
 *
 * Parameters	: none
 * Return		: return the of the DIP switch
 * Notes		: 
 *
 */

unsigned dips_read (void) 
{
	return SWITCH_MASK & *IOPDATA;
}

/* -- C_Entry --------------------------------------------------
 * 
 * Description	: standard entry into the C application 
 *
 * Parameters	: none
 * Return		: none...
 * Notes		: 
 *
 */

void C_Entry (void)
{
int dips;

	// initialize the segment display ..........................

	dips_init ();

	// infinite polling loop ...................................

	while ( FOREVER ) {		
		dips = dips_read ();
		dips_setsegment(numeric_display[dips]);
		dips_delay(0x1ffff0);
	} 

	// should never get to this code ...........................

	Exit();
}

/****************************************************************
 * END OF DIPS.C
 ****************************************************************/