蓝桥杯——定时扫描独立按键

一、原理部分

和定时扫描矩阵按键差不多的原理，只不过跳线帽连接2和3。不明白的可以看这篇博客。
定时扫描矩阵

二、代码部分

实验平台：CT107D
实验芯片：stc15f2k60s2
实验现象：S7打开蜂鸣器，S6关闭蜂鸣器，S5打开继电器，S4关闭继电器
代码如下（这里使用了标志位控制蜂鸣器和继电器）

#include

#define uchar unsigned char
#define uint unsigned int

sbit buzz = P0^6;
sbit relay = P0^4;

bit buzz_flag = 0;
bit relay_flag = 0;

sbit key_in1 = P3^0;
sbit key_in2 = P3^1;
sbit key_in3 = P3^2;
sbit key_in4 = P3^3;

uchar keysta[] = {1,1,1,1};
uchar kaymap[] = {1,2,3,4};
//uchar code duan[]={0x3F,0x06,0x5B,0x4F,0x66,0x6D,0x7D,0x07,0x7F,0x6F,0x00};//定义段码数组
//uchar disbuff[8];//定义显示数字数字


void set_buzz()
{
	if(buzz_flag == 0)
	{
		P2 = P2&0x1f|0xa0;
		buzz = 0;
		P2 = P2&0x1f;
	}

	if(buzz_flag == 1)
	{
		P2 = P2&0x1f|0xa0;
		buzz = 1;
		P2 = P2&0x1f;
	}
}

void set_relay()
{
	if(relay_flag == 0)
	{
		P2 = P2&0x1f|0xa0;
		relay = 0;
		P2 = P2&0x1f;
	}

	if(relay_flag == 1)
	{
		P2 = P2&0x1f|0xa0;
		relay = 1;
		P2 = P2&0x1f;
	}
}

void keyscan()
{
	static uchar keybuff[]={0xff,0xff,0xff,0xff};
	uchar j;

	keybuff[0] = keybuff[0]<<1|key_in1;	
	keybuff[1] = keybuff[1]<<1|key_in2;
	keybuff[2] = keybuff[2]<<1|key_in3;
	keybuff[3] = keybuff[3]<<1|key_in4;

	for(j=0;j<4;j++)
	{
		if((keybuff[j]&0x0f) == 0x00)
		{
			 keysta[j]=0;
		}
		
		else if((keybuff[j]&0x0f) == 0x0f)
		{
			 keysta[j]=1;
		}	
	}
}

void keyfun(uchar key_value)
{
	switch(key_value)
	{
		case 1:buzz_flag=1;break;
		case 2:buzz_flag=0;break;
		case 3:relay_flag=1;break;
		case 4:relay_flag=0;break;
	}
}

void keydrive()
{
	static uchar keyback[]={1,1,1,1};
	uchar i;
	for(i=0;i<4;i++)
	{
		if(keysta[i]!=keyback[i])
		{
			if(keysta[i] != 0)
			{
				keyfun(kaymap[i]);
			}
			keyback[i]=	keysta[i];
		}		
	}
}

void Timer0Init(void)		//1毫秒@12.000MHz
{
	AUXR |= 0x80;		//定时器时钟1T模式
	TMOD &= 0xF0;		//设置定时器模式
	TL0 = 0x20;		//设置定时初值
	TH0 = 0xD1;		//设置定时初值
	TF0 = 0;		//清除TF0标志
	TR0 = 1;		//定时器0开始计时
	ET0 = 1;
	EA = 1 ; 
}

void time0() interrupt 1
{
	 keyscan();
}

void main()
{
	Timer0Init();
	while(1)
	{
		set_buzz();
		set_relay();
		keydrive();
	}
}