key.c

74hc165d 做的键盘扩展程序 avr实现 独立按键 9个 与avr串行通信

#include <iom8v.h>
void Delay(int x) 
	{
	unsigned int a, b;
	for (a = 100; a>0; a--)
		for (b = 1000; b>0; b--);
	}
void main()
	{
	unsigned int i,j,ACC;
	//ACC=0X000;
    DDRC=0XFE;
	PORTC=0XFF;
	DDRB=0XFF;
	PORTB=0XFF;
	DDRD=0XFF;
	PORTD=0X00;
	while (1)
		{	
		//PORTB=0x00;
			PORTC&=0B11111101;
			
			//Delay(1);
			PORTC|=0B00000010;
	   		 for(i=9;i>0;i--)
			 {
			  	ACC=ACC<<1;
				PORTC&=0B11111011;
				ACC|=(PINC&01);
				PORTC|=0B00000100;		 
			 }
			// PORTC=0xfB;
			ACC= ACC&0x1ff;
			if(ACC==0xff)
			{PORTB=0X00;
			}
			else
			 PORTB=ACC;
			// PORTC=0xff;
			 Delay(250);
		 }
     }