ledshow.c

AVR典型实例.rar

/*
   LEDShow.C
   4位共阴数码管显示例程


*/
#include <avr/io.h>

#define uchar8 unsigned char

const uchar8 LedNum[] ={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f};

void delay()
{
	int i;
	for(i=0;i<600;i++)
		;
}

void LEDShow(int num)
{
	uchar8 i,tmp,curnum;
	int tmpnum;

		tmp = 0xef;
		tmpnum = num;
		for(i=0;i<4;i++)
		{	
			curnum = tmpnum % 10;
			tmpnum = tmpnum / 10;
			PORTA = tmp;
			PORTC = LedNum[curnum];
			delay();
			tmp = (tmp << 1) + 0x1;
		}

}
int main(void)
{
	int num; /*  要显示的数字 */
	char count = 0;
	DDRC = 0xff;
	DDRA = 0xff;
	
	num = 0;
	while(1)
	{
		LEDShow(num);
		count ++;
		if(count > 40)
		{
			num ++;
			count = 0;
		}
		if(num > 3000)
			num = 0;
		delay();

	}
    return 0;
}