按钮切换300/600档位计时时，数码管暗下来

帮忙看看是程序哪里有问题。




```#include <STC15F2K60S2.H>

#define uchar unsigned char
#define uint  unsigned int
sbit led = P1^7;
sbit key1 = P5^4; //时间切换键
sbit key2 = P1^6; //启动按键
sbit we1 = P1^1;  //数码管位端口
sbit we2 = P1^3;
sbit we3 = P1^2;
uchar knum;
bit k1f=0;                  //key1按键按下次数计数变量
uchar cont;                  //中断次数变量
uint cont1=30,cont2=300,cont3=600;        //定义时间变量并赋值30秒，300秒，600秒
uchar code LedTab[]=  {0xef,0x8c,0xb7,0xbe,0xdc,0x7e,0x7f,0xac,0xff,0xfe};
void delay()
        
{
    unsigned char i;

    i = 3;
    while (--i);
}

void Delay10ms()        //@11.0592MHz
{
    unsigned char i, j;

    i = 108;
    j = 145;
    do
    {
        while (--j);
    } while (--i);
}

void Delay30us()        //@11.0592MHz
{
    unsigned char i;
    i = 80;
    while (--i);
}

void display1(uint shu)
{
    

    we1 = 0;we2 = 1; we3 = 1;
    P3= LedTab[shu/100];
    we1=1;
    P3=0x00;

    we1 = 1;we2 = 0; we3 = 1;
    P3 = LedTab[shu%100/10];
    we2 = 1;
    P3 = 0x00;
    
    
    we1 = 1;we2 = 1; we3 = 0;
    P3 = LedTab[shu%10];
    
    we3 = 1;
    P3 = 0x00;
    
}
void keyscan()
{      if(key1==0)
 {      Delay30us();
       if(k1f==0)
 {        k1f=1;  knum++;
       if(knum==4)
          knum=0;
                } }
                else k1f=0;
     if(key2 == 0)
{         Delay30us();
       if(key2 == 0)         //key2按下
            TR0=~0;      }
            
        
                   //    led = 0;         //点亮LED，松手后启动倒计时
                             //这句后面不加分号，下一句调用显示函数，按键时数码管才不会灭
                     
      if(knum==0)
       {  display1(cont1); 


      if(knum==1)
         display1(cont2);  
      if(knum==2)
         display1(cont3);
         if(knum==3)
         P3=0x00; }  
                            /*   switch(knum)
                                {
                                         case 0: display1(cont1);  break;
                                         case 1: display1(cont2);  break;
                                         case 2: display1(cont3);  break;
                                }    */
        
![img](https://img-mid.csdnimg.cn/release/static/image/mid/ask/269302249786192.jpg "#left")

![img](https://img-mid.csdnimg.cn/release/static/image/mid/ask/019022249786124.jpg "#left")

```

数码管驱动常识:消隐,送段值,送位值,延时.延时长短决定亮度以及闪烁度.看数码管驱动没延时.