2020物联网实验室的考核题目

 

 

 unsigned char code table[]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90};

	int time=99;
	int t1=0;
	int t2=0;
	int i=0;

void Timer0Init(void)     //1毫秒
{
  EA=1;
  ET0=1;
  TR0 = 1;        //定时器0开始计时
  TMOD = 0x01;    //设置定时器模式
  TL0 = 0xCD;     //设置定时初值
  TH0 = 0xD4;     //设置定时初值
}

int main()
{
 	led5=0;
 	Timer0Init();
  while(1)
  {
  t1=time/10;
  t2=time%10;
   W2=0;
   W3=1;
   P0=table[t2];
   delay(100);
   W2=1;
   W3=0;
   P0=table[t1]; 
   delay(100);
  }
return 0;
}


   void time_user()interrupt 1
 {
  TL0 = 0xCD;     //设置定时初值
  TH0 = 0xD4;     //设置定时初值
  i++;
  if(i==100)
  {
  led5=~led5;
  i=0;
  time--;
  if(time<0)
  {
  time=99;
  }
  }
 }

　　

 

 软件延时来实现呼吸灯，一路定时器控制FM

unsigned char code table[]={0xc0,0xf9,0xa4,0xb0,0x99,0x92,0x82,0xf8,0x80,0x90};

	int time=99;
	int t1=0;
	int t2=0;
	int i=0;

void Timer0Init(void)     //1毫秒
{
  EA=1;
  ET0=1;
  TR0 = 1;        //定时器0开始计时
  TMOD = 0x01;    //设置定时器模式
  TL0 = 0xCD;     //设置定时初值
  TH0 = 0xD4;     //设置定时初值
}

int main()
{
 	led5=0;
 	Timer0Init();
  while(1)
  {
  t1=time/10;
  t2=time%10;
   W2=0;
   W3=1;
   P0=table[t2];
   delay(100);
   W2=1;
   W3=0;
   P0=table[t1]; 
   delay(100);
  }
return 0;
}


   void time_user()interrupt 1
 {
  TL0 = 0xCD;     //设置定时初值
  TH0 = 0xD4;     //设置定时初值
  i++;
  if(i==100)
  {
  led5=~led5;
  i=0;
  time--;
  if(time<0)
  {
  time=99;
  }
  }
 }

　　其实这个东西挺坑的，定时器有优先级，所以选择了折中的办法

 

C语言题目

int main()
{
	int N = 0;
	for (int x = 1; x <= 3; x++)
	{
		for (int y = 0; y <= 3; y++)
		{
			for (int z = 0; z <= 3; z++)
			{
				if (x == y || x == z || z == y)
				{
					continue;
				}
				printf("%d%d%d\n", x, y, z);
				N++;
			}
		}
	}
	printf("共计%d个\n", N);
	system("pause");
	return 0;
}

　第一个不写了，数码管平时也用不到