AT89C52一键多功能(短按、长按)程序

短按(按下持续时间小于3s)一次数码管显示加1，同时流水灯计数加1。

长按(按下持续时间大于3s)时，数码管显示每500ms加1，同时流水灯每500ms计数加1。

#include<reg52.h> 
typedef unsigned char uchar; 
typedef unsigned int uint; 
#define NOKEY 0 
#define KEYDOWN 1 
#define KEYUP 2 
uchar keystate; 
sbit key=P2^7; 
void keyscan(void); 
uchar timeflag; 
uchar code table[]= 
{ 
    0x80,0xf2,0x48,0x60, 
    0x32,0x24,0x04,0xf0, 
    0x00,0x20,0x10,0x06, 
    0x8c,0x42,0x0c,0x1c 
}; 
uchar i; 
void main(void) 
{ 
    TMOD=0x10; 
    TH1=(65536-50000)/256; 
    TL1=(65536-50000)%256; 
    EA=1; 
    ET1=1; 
    TR1=1; 
    while(1) 
    { 
        if(timeflag) 
        { 
            timeflag=0; 
            keyscan(); 
        } 
    } 
} 
void keyscan(void) 
{ 
    static uchar iscontinue=0; 
    P2 |=0x80; 
    switch(keystate) 
    { 
        case NOKEY: 
            if(key==0) 
            { 
                keystate=KEYDOWN; 
                return; 
            } 
            else 
            { 
                keystate=NOKEY;          
                return; 
            } 
        case KEYDOWN: 
            if(key==0) 
            { 
                keystate=KEYUP; 
                return; 
            } 
            else 
            { 
                keystate=NOKEY;          
                return; 
            }            
        case KEYUP: 
            if(key==0) 
            { 
                keystate=KEYUP; 
                iscontinue++; 
                if(iscontinue==255) 
                    iscontinue=60; 
                if(iscontinue>=60) 
                { 
                    if(iscontinue%10==0) 
                    { 
                        P2+=1; 
                        P1=table[i++]; 
                        if(i>=16) 
                            i=0; 
                    } 
                } 
                return; 
            } 
            else 
            { 
                keystate=NOKEY; 
                if(iscontinue<60) 
                { 
                    P2+=1; 
                    P1=table[i++]; 
                    if(i>=16) 
                        i=0;                     
                } 
                iscontinue=0;            
                return; 
            } 
    } 
} 
void timer1isr() interrupt 3 
{ 
    TH1=(65536-50000)/256; 
    TL1=(65536-50000)%256; 
    timeflag=1; 
}