十字路口交通灯设计课程设计论文(5)

}

}

case 0xbe: key=3; break; case 0x7e: key=10;

break;

//

等待按键释放

}

while(temp!=0xf0) { }

temp=P;

temp=temp&0xf0;

P=0xfd;

temp=P;

temp=temp&0xf0; if(temp!=0xf0) {

delay(10); temp=P;

temp=temp&0xf0; if(temp!=0xf0) { temp=P;

switch(temp) { }

while(temp!=0xf0) { temp=P;

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temp=P;

case 0xed: key=4; break; case 0xdd:

key=5; break;

case 0xbd: key=6;

break; case 0x7d: key=B;

break;

temp=temp&0xf0;

} } } P=0xfb; temp=P;

temp=temp&0xf0; if(temp!=0xf0) { delay(10); temp=P;

temp=temp&0xf0; }

if(temp!=0xf0) { }

temp=P; switch(temp) { }

case 0xeb: key=7;

break; case 0xdb: key=8; break; case 0xbb: key=9; break; case 0x7b:

key=12; break;

while(temp!=0xf0) { }

temp=P;

temp=temp&0xf0;

P=0xf7; temp=P;

temp=temp&0xf0; if(temp!=0xf0) {

delay(10); temp=P;

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}

temp=temp&0xf0; if(temp!=0xf0) { temp=P; switch(temp) }

{ } { }

temp=P;

temp=temp&0xf0; case 0xe7:

key=14; break; key=0; break;

case 0xd7:

case 0xb7: key=15; break; case 0x77:

key=13; break;

while(temp!=0xf0)

}

return(key);

延时程序：

#include

void delay(unsigned int xms) { }

unsigned int i,j; for(i=xms;i>0;i--) for(j=123;j>0;j--);

//延时程序

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