led.c

LED的检测程序

#define LED port40                           
volatile ioport unsigned int port40;

extern void LEDTest(unsigned int count);
extern void delay(unsigned int period);
extern void LEDflash(unsigned int id); 

void LEDTest(unsigned int count)
{
	unsigned char i,t;
	for(;count!=0;count--)
	{
	for(t=0,i=1;t<8;i=i<<1,t++)
	{
		LED=~i;
		delay(500);
	}
	}
	LED=0xffff;
}


void delay(unsigned int period)
{
    int periodi, periodj;
    
    for(periodi=0; periodi<period; periodi++)
    {
        for(periodj=0; periodj<period>>1; periodj++);
    }
}

void LEDflash(unsigned int id)
{
	while(1)
	{
	
		LED=id;
		delay(1500);
		LED=0xffff;
		delay(1500);
	}
}