key.c

键盘应用程序

#include<reg51.h>
#include<intrins.h>
sbit P34=0xb4;
sbit P35=0xb5;
//定义显示代码
char code disp[]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90,0x88,0x83,0xc6,0xa1,0x86,0x8e};
//声明获得键码函数
unsigned char get_char(void);
//声明延时函数
void delay(void);
//声明显示函数
void display(char  dispchar);

main(){
unsigned char keybuf,count;
SCON=0;
ES=0;
EA=0;
count=0;

while(1) 
{
keybuf=get_char();

display(keybuf);

}
}

unsigned char get_char(void){
unsigned char column=0,mask=0x00,key_code;
TI=0;
SBUF=mask;
while(TI==0);
while(1){
while((P34&P35)!=0);
delay();
if((P34&P35)!=0) continue;
else break;
}
mask=0xfe;
while(1) 
{
TI=0;
SBUF=mask;
while(TI==0);
if((P34&P35)!=0)
{
mask=_crol_(mask,1);
column++;
if(column>=8) column=0;
continue;
}
else break;
}
if(P34==0) key_code=column;
else key_code=8+column;
return(key_code);

}

void delay(void){
unsigned int i=0;
while(i--);
}

void display(char  dispchar)
{
P1=disp[dispchar];
}