51单片机用一个按键控制八个灯，四种形态

可以使用二进制编码的方式实现。首先将八个灯的状态用一个八位的二进制数表示，然后用一个按键来控制这个二进制数的值。每按一次按键，二进制数加一，当二进制数的值大于等于四时，灯的状态就会发生变化，形成四种不同的形态。以下是示例代码：

#include <reg51.h>

sbit LED1 = P1^0;
sbit LED2 = P1^1;
sbit LED3 = P1^2;
sbit LED4 = P1^3;
sbit LED5 = P1^4;
sbit LED6 = P1^5;
sbit LED7 = P1^6;
sbit LED8 = P1^7;

sbit KEY = P3^2;

void delay(unsigned int t)
{
    while(t--);
}

void main()
{
    unsigned char state = 0;
    unsigned char last_key = 1;
    
    while(1)
    {
        if(KEY == 0 && last_key == 1)
        {
            state++;
            if(state >= 4)
            {
                state = 0;
            }
        }
        last_key = KEY;
        
        switch(state)
        {
            case 0:
                LED1 = 0;
                LED2 = 0;
                LED3 = 0;
                LED4 = 0;
                LED5 = 0;
                LED6 = 0;
                LED7 = 0;
                LED8 = 0;
                break;
            case 1:
                LED1 = 1;
                LED2 = 0;
                LED3 = 0;
                LED4 = 0;
                LED5 = 0;
                LED6 = 0;
                LED7 = 0;
                LED8 = 0;
                break;
            case 2:
                LED1 = 1;
                LED2 = 1;
                LED3 = 0;
                LED4 = 0;
                LED5 = 0;
                LED6 = 0;
                LED7 = 0;
                LED8 = 0;
                break;
            case 3:
                LED1 = 1;
                LED2 = 1;
                LED3 = 1;
                LED4 = 1;
                LED5 = 1;
                LED6 = 1;
                LED7 = 1;
                LED8 = 1;
                break;
        }
        
        delay(1000);
    }
}

这段代码使用 P1 口控制八个 LED 灯，P3.2 口接一个按键。每按一次按键，灯的状态就会发生变化。