以下是一个4乘4的键盘扫描程序,好像没有延时去抖动什么的,不知道有没有问题,麻烦各位高手帮帮忙看一下有没有问题? 还需不需要加什么?
void Tkey(void)
{
uchar readkey;
uchar x_temp,y_temp;
P1=0x0f;
x_temp=P1&0x0f;
if(x_temp==0x0f) goto keyout;
P1=0xf0;
y_temp=P1&0xf0;
readkey=x_temp|y_temp;
readkey=~readkey;
switch(readkey)
{
case 0x11:key=0; break;
case 0x21:key=1; break;
case 0x41:key=2; break;
case 0x81:key=3; break;
case 0x12:key=4; break;
case 0x22:key=5; break;
case 0x42:key=6; break;
case 0x82:key=7; break;
case 0x14:key=8; break;
case 0x24:key=9; break;
case 0x44:key=10;break;
case 0x84:key=11;break;
case 0x18:key=12;break;
case 0x28:key=13;break;
case 0x48:key=14;break;
case 0x88:key=15;break;
default: key=16;break;
}
keyout:_nop_();
}
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