键盘扫描（长短按键有效）

#include "at89x51.h"
unsigned char led[]={
0x3f, 0x06, 0x5b, 0x4f, 0x66, 0x6d, 0x7d, 0x07,    //0-7
0x7f, 0x6f, 0x77, 0x7c, 0x39, 0x5e, 0x79, 0x71    //8-F
};
unsigned int time,KEY,num,Long,Short,PK;
void delay(unsigned char a)
{
int i,j;
for(i=0;i<a;i++)
for(j=0;j<100;j++);
}
void time0(void) interrupt 1
{
TH0=(65535-5000)/256;
TL0=(65535-5000)%256;
if(P3_5==0) //按键按下
{
KEY++;
if(KEY>200)    //长按
{
Long=1;


// KEY=0;
}


}
else{