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Kod: Markera allt

void delay(void) {
  unsigned int foo = 65535;
  while (foo-- > 0) {}
}

Kod: Markera allt

/*
 *	Delay functions for HI-TECH C on the PIC
 *
 *	Functions available:
 *		DelayUs(x)	Delay specified number of microseconds
 *		DelayMs(x)	Delay specified number of milliseconds
 *
 *	Note that there are range limits: x must not exceed 255 - for xtal
 *	frequencies > 12MHz the range for DelayUs is even smaller.
 *	To use DelayUs it is only necessary to include this file; to use
 *	DelayMs you must include delay.c in your project.
 *
 */

/*	Set the crystal frequency in the CPP predefined symbols list in
	HPDPIC, or on the PICC commmand line, e.g.
	picc -DXTAL_FREQ=4MHZ
	
	or
	picc -DXTAL_FREQ=100KHZ
	
	Note that this is the crystal frequency, the CPU clock is
	divided by 4.

 *	MAKE SURE this code is compiled with full optimization!!!
	
 */

#ifndef	XTAL_FREQ
#define	XTAL_FREQ	4MHZ		/* Crystal frequency in MHz */
#endif

#define	MHZ	*1000L			/* number of kHz in a MHz */
#define	KHZ	*1			/* number of kHz in a kHz */

#if	XTAL_FREQ >= 12MHZ

#define	DelayUs(x)	{ unsigned char _dcnt; \
			  _dcnt = (x)*((XTAL_FREQ)/(12MHZ)); \
			  while(--_dcnt != 0) \
				  continue; }
#else

#define	DelayUs(x)	{ unsigned char _dcnt; \
			  _dcnt = (x)/((12MHZ)/(XTAL_FREQ))|1; \
			  while(--_dcnt != 0) \
				  continue; }
#endif

extern void DelayMs(unsigned char);

Kod: Markera allt

/*
 *	Delay functions
 *	See delay.h for details
 *
 *	Make sure this code is compiled with full optimization!!!
 */

#include	"delay.h"

void
DelayMs(unsigned char cnt)
{
#if	XTAL_FREQ <= 2MHZ
	do {
		DelayUs(996);
	} while(--cnt);
#endif

#if    XTAL_FREQ > 2MHZ	
	unsigned char	i;
	do {
		i = 4;
		do {
			DelayUs(250);
		} while(--i);
	} while(--cnt);
#endif
}