EEPW论坛

//用开发板制作的一个计算器实验
//下面是源代码，

#include<reg52.h>
#include<stdlib.h>
#include<stdio.h>
#define LCD_DATA P0       //lcd数据显示
#define LCD_KEY  P2        //键盘接口
#define uchar unsigned char
#define uint  unsigned int

sbit LCD_RS=P1^0;   // LCD 1602的RS 接口  
sbit LCD_RW=P1^1;  //LCD 1602的RW 接口
sbit LCD_E=P1^2;      //LCD 1602的E使能端接口

//是否有按键按下
bit  isKeyPress;
//按键所选择键值          
uchar  selectKey;
//记录连续输入数字的个数  
uchar  count;   
//记录连续接收到的数字，最多输入14位
uchar  receivedData[14];
//记录存储结果
long result;
//输入数据暂存
long rectmp1,rectmp2; 
//记录输入符号
uchar sign;

//定时器0
void Timer0();
//LCD初始化     
void lcdInit();
//LCD写数据       
void lcdWriteData(uchar dat);
//LCD写命令     
void lcdWriteCommand(uchar com);
//最小延时1ms时参数为1    
void delay1ms();      
//键盘扫描程序 
uchar scanKeyboard();
//将字符写入第Y行第x个位置 
void displayCharAt(uchar x,uchar y,uchar dat);  
//显示字符串在指定的位置 
void displayStringAt(uchar x,uchar y,uchar *str); 
//在当前字符的下一个位置显示字符
void displayChar(uchar dat);      
//在当前字符的下一个位置显示字符串
void displayString(uchar *str); 
//处理从键盘得到的按键值
void keyProcess(uchar key);
//清除LCD中的所有显示，并将光标至于地址0      
void clearDisplay();
//将字符串转换成整形
uint stringToInt(uchar *str);
//复位
void lcdReset();

//在指定位置显示字符 
void displayCharAt(uchar x,uchar y,uchar dat)
{
 uchar address;
 if(y==1)
         address=0x80+x;
 else
         address=0xc0+x;
 lcdWriteCommand(address);
 lcdWriteData(dat);
}

void displayChar(uchar dat)
{
 lcdWriteData(dat);
}
//在指定位置显示字符串
void displayStringAt(uchar x,uchar y,uchar *str)
{
  uchar address;
    uchar i;
 if(y==1)
         address=0x80+x;
 else
         address=0xc0+x;
 for(i=0;str[i]!='\0';i++)
 {

 //  lcdWriteCommand(address++);
  lcdWriteData(str[i]);
 }
}

void displayString(uchar *str)
{
    uchar i;
 for(i=0;str[i]!='\0';i++)
  lcdWriteData(str[i]);
}
void lcdInit()     //lcd初始化函数
{ 
 uchar i;

 count=0;
 selectKey=0;
 isKeyPress=0;
 result=0;
 rectmp1=0;
 rectmp2=0;
 sign=' ';  //空格表示没有输入符号
 for(i=0;i<14;i++)
  receivedData[i]='\0';

    lcdWriteCommand(0x38);//设置8位格式，2行，5x7
  lcdWriteCommand(0x0C);//整体显示，关光标，不闪烁
    lcdWriteCommand(0x06);//设定输入方式，增量不移位
    lcdWriteCommand(0x01);//清除屏幕显示
  delay1ms();
}

void lcdWriteData(uchar dat)    //lcd写数据
{
 LCD_RS=1;  //写数据
 LCD_RW=0;
 LCD_E=0;
 LCD_DATA=dat;
 LCD_E=1;
 delay1ms();
 LCD_E=0;
 delay1ms();
}

void lcdWriteCommand(uchar com)    //lcd写命令
{
 LCD_RS=0;  //写命令
 LCD_RW=0;
 LCD_E=0;
 LCD_DATA=com;
 LCD_E=1;
 delay1ms();
 LCD_E=0;
 delay1ms();
}
uchar scanKeyboard()      //键盘扫描程序
{
     uchar  tmp1,tmp2,key;
      LCD_KEY=0XFe;        //第一行
      tmp1=LCD_KEY;
   tmp2=tmp1&0xf0;
      if(tmp2!=0xf0)
      {
           delay1ms();               //键抖动处理
           tmp1=LCD_KEY;
           if((tmp1&0xf0)==tmp2)
           {
                switch(tmp2)
                {
                  case 0xe0:key='7';break;
                  case 0xd0:key='8';break;
                  case 0xb0:key='9';break;
                  case 0x70:key=0xfd;break;  //0xfd除号在1602液晶中的代码
                }
                while(tmp2!=0xf0)  //键释放处理
                {
                  tmp2=LCD_KEY;
      tmp2=tmp2&0xf0;
                }
                isKeyPress=1;     //键按标志置1
                return(key);
           }
      }

      LCD_KEY=0XFd;        //第二行
      tmp1=LCD_KEY;
   tmp2=tmp1&0xf0;
      if(tmp2!=0xf0)
      {
           delay1ms();               //键抖动处理
           tmp1=LCD_KEY;
           if((tmp1&0xf0)==tmp2)
           {
                switch(tmp2)
                {
                  case 0xe0:key='4';break;
                  case 0xd0:key='5';break;
                  case 0xb0:key='6';break;
                  case 0x70:key='*';break;  //乘号
                }
                while(tmp2!=0xf0)  //键释放处理
                {
                  tmp2=LCD_KEY;
      tmp2=tmp2&0xf0;
                }
                isKeyPress=1;     //键按标志置1
                return(key);
           }
      }

   LCD_KEY=0XFb;        //第三行
      tmp1=LCD_KEY;
   tmp2=tmp1&0xf0;
      if(tmp2!=0xf0)
      {
           delay1ms();               //键抖动处理
           tmp1=LCD_KEY;
           if((tmp1&0xf0)==tmp2)
           {
                switch(tmp2)
                {
                  case 0xe0:key='1';break;
                  case 0xd0:key='2';break;
                  case 0xb0:key='3';break;
                  case 0x70:key='-';break;  //减号
                }
                while(tmp2!=0xf0)  //键释放处理
                {
                  tmp2=LCD_KEY;
      tmp2=tmp2&0xf0;
                }
                isKeyPress=1;     //键按标志置1
                return(key);
           }
      }

   LCD_KEY=0XF7;        //第四行
      tmp1=LCD_KEY;
   tmp2=tmp1&0xf0;
      if(tmp2!=0xf0)
      {
           delay1ms();               //键抖动处理
           tmp1=LCD_KEY;
           if((tmp1&0xf0)==tmp2)
           {
                switch(tmp2)
                {
                  case 0xe0:key='c';break;
                  case 0xd0:key='0';break;
                  case 0xb0:key='=';break;
                  case 0x70:key='+';break;  //
                }
                while(tmp2!=0xf0)  //键释放处理
                {
                  tmp2=LCD_KEY;
      tmp2=tmp2&0xf0;
                }
                isKeyPress=1;     //键按标志置1
                return(key);
           }
      }
  return(0);
}

void delay1ms()
{
    uchar a,b;
    for(b=199;b>0;b--)
        for(a=1;a>0;a--);
}

void keyProcess(uchar key)
{
  if('0'<=key&&key<='9')
  {
   if(count==0)
  { 
   uchar i;
  // clearDisplay();
   for(i=0;i<14;i++)
    receivedData[i]='\0';  
  }
 // if(count==14)  //溢出则显示错误
 //  displayString(" data is limited ");
   displayChar(key); //显示输入字符
  receivedData[count]=key;
  count++;
  }
  else if(key=='+'||key=='-'||key=='*'||key==0xfd)
  { 
   uchar i;
  if(receivedData[0]!='\0')
    rectmp1=atol(receivedData);
  sign=key;

  count=0;
//  clearDisplay();
  displayChar(key);
  for(i=0;i<14;i++)
   receivedData[i]='\0';
  }
  else if(key=='=')
  {
   
   char buf[10];
  uint i;
  clearDisplay();
   rectmp2=atol(receivedData);
  switch(sign)
  {
  case '+':    //加
   rectmp1+=rectmp2;
   break;
  case '-':    //减
   rectmp1-=rectmp2;
   break;
  case '*':    //乘
   rectmp1*=rectmp2;
   break;
  case 0xfd:    //除
   rectmp1/=rectmp2;
   break;
  }
   
  //将计算结果转化成字符串
  sprintf(buf,"%ld",rectmp1);  
   displayString(buf);
  count=0;
  for(i=0;i<14;i++)
   receivedData[i]='\0'; 
  }
  else if(key=='c')
  {
  lcdReset();    //复位
  } 
}

//复位
void lcdReset()
{
 lcdInit(); 
}
//清除LCD中的所有显示，并将光标至于地址0 
void clearDisplay()
{
 lcdWriteCommand(0x01);
 lcdWriteCommand(0x80);
}
void Timer0() interrupt 1
{
    TH0 = 0x3C;
    TL0 = 0x0B0;
}
void main()
{
  lcdInit();
  
     TMOD = 0x01;  //定时器0，方式1
     TH0 = 0x3C;   //50us,晶振频率为12M
     TL0 = 0x0B0;
     EA = 1;    //允许溢出中断设置
     ET0 = 1;
     TR0 = 1;   //开始计时
  while(1)
  {
   selectKey=scanKeyboard();
   if(selectKey!=0)
   {
    keyProcess(selectKey);
   }
    
  }

}