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cal3.c
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/**************************************************************************************
* 浮点数四则运算计算器 *
* *
* 连接方法：Jp8连JP4,JP9连JP5,把1602液晶插入 *
* *
***************************************************************************************/
#include <reg51.h> //此文件中定义了51的一些特殊功能寄存器
#define uchar unsigned char
#define uint unsigned int
sbit EN = P2^7; //LCD的使能引脚
sbit RS = P2^6; //LCD数据命令选择端
sbit RW = P2^5; //LCD的读写选择端
//3X4矩阵键盘键值表
uchar KEY_CODE[] = { 0xed,0xdd,0xbd,0x7d,
0xeb,0xdb,0xbb,0x7b,
0xe7,0xd7,0xb7,0x77};
//定义字符键值表
uchar CHAR_TABLE[] = {0x30,0x31,0x32,0x33, //0 1 2 3
0x34,0x35,0x36,0x37, //4 5 6 7
0x38,0x39,0x28,0x29, //8 9 ( )
0x2B,0x2D,0x2A,0x2F, //+ - * /
0x2E,0x25,0x43,0x3D};//. % C =
//错误信息
uchar MATH_ERROR[] = {0x4D, 0x41, 0x54, 0x48, 0x20, 0x45, 0x52, 0x52, 0x4F, 0x52, 0x21};
uchar BUFFER[16]={' '};//定义长度等于液晶屏一行的缓冲区
uchar length = 0; //当前缓冲区中字符个数
uchar status = 0; //状态编号
xdata uchar stack1[64];
xdata float stack2[48];
xdata uchar pt1 = 0;
xdata uchar pt2 = 0;
void scanChar(uchar *ch);//从矩阵键盘中获取值
void print(uchar *arr,uint end);//打印字符串
void delay5MS();//短延时函数
void delay100MS();//较长延时函数
void writeCMD(uchar com);//写命令子程序
void showOneChar(uchar dat);//写数据子程序
void init();//初始化子程序，初始化液晶显示屏
void clear();//清除显示屏上的显示
float oprand1;
float oprand2;
float oprand3;
uchar op1, op2, op3, ch;
long weight;
//定义状态函数
void status0(); void status1();
void status2(); void status3();
void status4(); void status5();
void status6(); void status7();
void status8(); void status9();
void status10(); void status11();
void status12(); void status13();
void status14(); void status15();
void status16(); void status17();
void status18(); void status19();
void status20(); void status21();
void status22();
//将小数转换为字符串
void floatToString();
void clearAll();
float fabs(float x);
void sqrtNewton();
void showError();
void PushStack()
{
stack1[pt1++] = status;
stack1[pt1++] = op1;
stack1[pt1++] = op2;
stack1[pt1++] = op3;
stack2[pt2++] = oprand1;
stack2[pt2++] = oprand2;
stack2[pt2++] = oprand3;
oprand1 = oprand2 = oprand3 = 0;
weight = 10;
status = 0;
}
void PopStack()
{
float temp;
uchar temppt1;
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch == '+' || ch == '-' || ch == '*' || ch == '/' || ch == '=' || ch == ')')
{
temppt1 = pt1;
temp = oprand1;
if (pt1 != 0)
{
op3 = stack1[--pt1];
op2 = stack1[--pt1];
op1 = stack1[--pt1];
status = stack1[--pt1];
oprand3 = stack2[--pt2];
oprand2 = stack2[--pt2];
oprand1 = stack2[--pt2];
}
if (status == 5)
{
oprand2 = temp;
if (ch == '+' || ch == '-' || ch == '*' || ch == '/' || ch == '=' || ch == ')')
{
op2 = ch;
status = 16;
}
}
else if (status == 6)
{
oprand3 = temp;
if (ch == '+' || ch == '-' || ch == '*' || ch == '/' || ch == '=' || ch == ')')
{
op2 = ch;
status = 11;
}
}
else if (status == 17)
{
oprand3 = temp;
if (ch == '+' || ch == '-' || ch == '*' || ch == '/' || ch == '=' || ch == ')')
{
op3 = ch;
status = 22;
}
}
else if (status == 0)
{
oprand1 = temp;
if (ch == '+' || ch == '-')
{
oprand2 = 0;
status = 5;
}
else if (ch == '*' || ch == '/')
{
oprand3 = 0;
status = 6;
}
}
}
else
{
length--;
status = 'm';
return;
}
}
void main()
{
init();
length = 0;
status = 0;
oprand1 = 0;
while (1)
{
switch (status)
{
case 0:
status0();
break;
case 1:
status1();
break;
case 2:
status2();
break;
case 3:
status3();
break;
case 4:
status4();
break;
case 5:
status5();
break;
case 6:
status6();
break;
case 7:
status7();
break;
case 8:
status8();
break;
case 9:
status9();
break;
case 10:
status10();
break;
case 11:
status11();
break;
case 12:
status12();
break;
case 13:
status13();
break;
case 14:
status14();
break;
case 15:
status15();
break;
case 16:
status16();
break;
case 17:
status17();
break;
case 18:
status18();
break;
case 19:
status19();
break;
case 20:
status20();
break;
case 21:
status21();
break;
case 22:
status22();
break;
case 'm':
PopStack();
}
clear();
print(BUFFER,length);
}
}
void floatToString()
{
uchar i, tmp;
long oprand1Int, floatInt;
float temp, oprand1Float;
if (fabs(oprand1) > 1000000000)
showError();
temp = oprand1 > 0 ? oprand1 : -oprand1;
oprand1Int = temp;
oprand1Float = temp - oprand1Int;
oprand1Float *= 100000;
floatInt = oprand1Float;
length = 0;
if (floatInt == 0)
BUFFER[length++] = 0;
while (floatInt > 0)
{
BUFFER[length++] = floatInt % 10;
floatInt /= 10;
}
for (; length < 5; length++)
BUFFER[length] = 0;
BUFFER[length++] = '.';
if (oprand1Int == 0)
BUFFER[length++] = 0;
while (oprand1Int > 0)
{
BUFFER[length++] = oprand1Int % 10;
oprand1Int /= 10;
}
if (oprand1 < 0)
BUFFER[length++] = '-';
for(i = length-1; i >= length / 2; i--)
{
tmp = BUFFER[i];
BUFFER[i] = BUFFER[length-1-i];
BUFFER[length-1-i] = tmp;
}
}
float fabs(float x)
{
return x > 0 ? x : -x;
}
/*
void sqrtNewton()
{
float x = oprand1;
float y = 0.0;
while (fabs(x-y) > 0.00001)
{
y = x;
x = 0.5 * (x + oprand1/x);
}
oprand1 = x;
}*/
void status0()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch == '-')
status = 1;
else if (ch >= 0 && ch <= 9)
{
oprand1 = ch;
status = 2;
}
else if (ch == '.')
{
weight = 10;
status = 4;
}
/*
else if (ch == 'S')
{
if (oprand1 < 0)
showError();
else
{
sqrtNewton();
floatToString();
}
}
else if (ch == 'Q')
{
oprand1 *= oprand1;
floatToString();
}
*/
else if (ch == '%')
{
if (oprand1 < 0)
showError();
else
{
oprand1 *= 100;
floatToString();
}
}
else if (ch == '(')
PushStack();
else if (ch == 'C')
clearAll();
else
length--;
}
void status1()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch >= 0 && ch <= 9)
{
oprand1 = oprand1 * 10 + ch;
status = 1;
}
else if (ch == '.')
{
weight = 10;
status = 3;
}
else if (ch == '+' || ch == '-')
{
oprand1 = -oprand1;
oprand2 = 0;
status = 5;
}
else if (ch == '*' || ch == '/')
{
oprand1 = -oprand1;
oprand3 = 0;
status = 6;
}
else if (ch == 'C')
clearAll();
else
length--;
}
void status2()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch >= 0 && ch <= 9)
{
oprand1 = oprand1 * 10 + ch;
status = 2;
}
else if (ch == '.')
{
weight = 10;
status = 4;
}
else if (ch == '+' || ch == '-')
{
oprand2 = 0;
status = 5;
}
else if (ch == '*' || ch == '/')
{
oprand3 = 0;
status = 6;
}
else if (ch == 'C')
clearAll();
else
length--;
}
void status3()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch >= 0 && ch <= 9)
{
oprand1 += ch/(float)weight;
weight *= 10;
status = 3;
}
else if (ch == '+' || ch == '-')
{
oprand1 = -oprand1;
oprand2 = 0;
status = 5;
}
else if (ch == '*' || ch == '/')
{
oprand1 = -oprand1;
oprand3 = 0;
status = 6;
}
else if (ch == 'C')
clearAll();
else
length--;
}
void status4()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch >= 0 && ch <= 9)
{
oprand1 += ch/(float)weight;
weight *= 10;
status = 4;
}
else if (ch == '+' || ch == '-')
{
oprand2 = 0;
status = 5;
}
else if (ch == '*' || ch == '/')
{
oprand3 = 0;
status = 6;
}
else if (ch == 'C')
clearAll();
else
length--;
}
void status5()
{
op1 = ch;
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
oprand2 = 0;
if (ch == '-')
status = 12;
else if (ch >= 0 && ch <= 9)
{
oprand2 = ch;
status = 13;
}
else if (ch == '.')
{
weight = 10;
status = 15;
}
else if (ch == 'C')
clearAll();
else if (ch == '(')
PushStack();
else
length--;
}
void status6()
{
op1 = ch;
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
oprand3 = 0;
if (ch == '-')
status = 7;
else if (ch >= 0 && ch <= 9)
{
oprand3 = ch;
status = 8;
}
else if (ch == '.')
{
weight = 10;
status = 10;
}
else if (ch == 'C')
clearAll();
else if (ch == '(')
PushStack();
else
length--;
}
void status7()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch >= 0 && ch <= 9)
{
oprand3 = oprand3 * 10 + ch;
status = 7;
}
else if (ch == '.')
{
weight = 10;
status = 9;
}
else if (ch == '+' || ch == '-' || ch == '*' || ch == '/' || ch == '=' || ch == ')')
{
oprand3 = -oprand3;
op2 = ch;
status = 11;
}
else if (ch == 'C')
clearAll();
else
length--;
}
void status8()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch >= 0 && ch <= 9)
{
oprand3 = oprand3 * 10 + ch;
status = 8;
}
else if (ch == '.')
{
weight = 10;
status = 10;
}
else if (ch == '+' || ch == '-' || ch == '*' || ch == '/' || ch == '=' || ch == ')')
{
op2 = ch;
status = 11;
}
else if (ch == 'C')
clearAll();
else
length--;
}
void status9()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch >= 0 && ch <= 9)
{
oprand3 += ch/(float)weight;
weight *= 10;
status = 9;
}
else if (ch == '+' || ch == '-' || ch == '*' || ch == '/' || ch == '=' || ch == ')')
{
oprand3 = -oprand3;
op2 = ch;
status = 11;
}
else if (ch == 'C')
clearAll();
else
length--;
}
void status10()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch >= 0 && ch <= 9)
{
oprand3 += ch/(float)weight;
weight *= 10;
status = 10;
}
else if (ch == '+' || ch == '-' || ch == '*' || ch == '/' || ch == '=' || ch == ')')
{
op2 = ch;
status = 11;
}
else if (ch == 'C')
clearAll();
else
length--;
}
void status11()
{
if (op1 == '*')
oprand1 *= oprand3;
else if (op1 == '/')
{
if (fabs(oprand3) < 0.00001)
showError();
oprand1 /= oprand3;
}
if (op2 == '=')
{
if (pt1 != 0)
showError();
else
{
floatToString();
status = 0;
}
}
else if (op2 == ')')
{
if (pt1 != 0)
status = 'm';
else
showError();
}
else if (op2 == '*' || op2 == '/')
status = 6;
else if (op2 == '+' || op2 == '-')
status = 5;
}
void status12()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch >= 0 && ch <= 9)
{
oprand2 = oprand2 * 10 + ch;
status = 12;
}
else if (ch == '.')
{
weight = 10;
status = 14;
}
else if (ch == '+' || ch == '-' || ch == '*' || ch == '/' || ch == '=' || ch == ')')
{
oprand2 = -oprand2;
op2 = ch;
status = 16;
}
else if (ch == 'C')
clearAll();
else
length--;
}
void status13()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch >= 0 && ch <= 9)
{
oprand2 = oprand2 * 10 + ch;
status = 13;
}
else if (ch == '.')
{
weight = 10;
status = 15;
}
else if (ch == '+' || ch == '-' || ch == '*' || ch == '/' || ch == '=' || ch == ')')
{
op2 = ch;
status = 16;
}
else if (ch == 'C')
clearAll();
else
length--;
}
void status14()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch >= 0 && ch <= 9)
{
oprand2 += ch/(float)weight;
weight *= 10;
status = 14;
}
else if (ch == '+' || ch == '-' || ch == '*' || ch == '/' || ch == '=' || ch == ')')
{
oprand2 = -oprand2;
op2 = ch;
status = 16;
}
else if (ch == 'C')
clearAll();
else
length--;
}
void status15()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch >= 0 && ch <= 9)
{
oprand2 += ch/(float)weight;
weight *= 10;
status = 15;
}
else if (ch == '+' || ch == '-' || ch == '*' || ch == '/' || ch == '=' || ch == ')')
{
op2 = ch;
status = 16;
}
else if (ch == 'C')
clearAll();
else
length--;
}
void status16()
{
if (op2 == '=')
{
if (pt1 != 0)
showError();
else
{
if (op1 == '+')
oprand1 += oprand2;
else if (op1 == '-')
oprand1 -= oprand2;
floatToString();
status = 0;
}
}
else if (op2 == '*' || op2 == '/')
status = 17;
else if (op2 == '+' || op2 == '-')
{
if (op1 == '+')
oprand1 += oprand2;
else if (op1 == '-')
oprand1 -= oprand2;
status = 5;
}
else if (op2 == ')')
{
if (op1 == '+')
oprand1 += oprand2;
else if (op1 == '-')
oprand1 -= oprand2;
if (pt1 != 0)
status = 'm';
else
showError();
}
}
void status17()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
oprand3 = 0;
if (ch == '-')
status = 18;
else if (ch >= 0 && ch <= 9)
{
oprand3 = ch;
status = 19;
}
else if (ch == '.')
{
weight = 10;
status = 21;
}
else if (ch == 'C')
clearAll();
else if (ch == '(')
PushStack();
else
length--;
}
void status18()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch >= 0 && ch <= 9)
{
oprand3 = oprand3 * 10 + ch;
status = 18;
}
else if (ch == '.')
{
weight = 10;
status = 20;
}
else if (ch == '+' || ch == '-' || ch == '*' || ch == '/' || ch == '=' || ch == ')')
{
oprand3 = -oprand3;
op3 = ch;
status = 22;
}
else if (ch == 'C')
clearAll();
else
length--;
}
void status19()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch >= 0 && ch <= 9)
{
oprand3 = oprand3 * 10 + ch;
status = 19;
}
else if (ch == '.')
{
weight = 10;
status = 21;
}
else if (ch == '+' || ch == '-' || ch == '*' || ch == '/' || ch == '=' || ch == ')')
{
op3 = ch;
status = 22;
}
else if (ch == 'C')
clearAll();
else
length--;
}
void status20()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch >= 0 && ch <= 9)
{
oprand3 += ch/(float)weight;
weight *= 10;
status = 20;
}
else if (ch == '+' || ch == '-' || ch == '*' || ch == '/' || ch == '=' || ch == ')')
{
oprand3 = -oprand3;
op3 = ch;
status = 22;
}
else if (ch == 'C')
clearAll();
else
length--;
}
void status21()
{
ch = 0xff;
scanChar(&ch);
if (length <= 16)
BUFFER[length++] = ch;
if (ch >= 0 && ch <= 9)
{
oprand3 += ch/(float)weight;
weight *= 10;
status = 21;
}
else if (ch == '+' || ch == '-' || ch == '*' || ch == '/' || ch == '=' || ch == ')')
{
op3 = ch;
status = 22;
}
else if (ch == 'C')
clearAll();
else
length--;
}
void status22()
{
if (op2 == '/' && fabs(oprand3) < 0.00001)
showError();
if (op3 == '=')
{
if (pt1 != 0)
showError();
else
{
if (op1 == '+' && op2 == '*')
oprand1 = oprand1 + oprand2 * oprand3;
else if (op1 == '-' && op2 == '*')
oprand1 = oprand1 - oprand2 * oprand3;
else if (op1 == '+' && op2 == '/')
oprand1 = oprand1 + oprand2 / oprand3;
else if (op1 == '-' && op2 == '/')
oprand1 = oprand1 - oprand2 / oprand3;
floatToString();
status = 0;
}
}
else if (op3 == ')')
{
if (op1 == '+' && op2 == '*')
oprand1 = oprand1 + oprand2 * oprand3;
else if (op1 == '-' && op2 == '*')
oprand1 = oprand1 - oprand2 * oprand3;
else if (op1 == '+' && op2 == '/')
oprand1 = oprand1 + oprand2 / oprand3;
else if (op1 == '-' && op2 == '/')
oprand1 = oprand1 - oprand2 / oprand3;
if (pt1 != 0)
status = 'm';
else
showError();
}
else if (op3 == '*' || op3 == '/')
{
if (op2 == '*')
oprand2 *= oprand3;
if (op2 == '/')
oprand2 /= oprand3;
op2 = op3;
status = 17;
}
else if (op3 == '+' || op3 == '-')
{
if (op1 == '+' && op2 == '*')
oprand1 = oprand1 + oprand2 * oprand3;
else if (op1 == '-' && op2 == '*')
oprand1 = oprand1 - oprand2 * oprand3;
else if (op1 == '+' && op2 == '/')
oprand1 = oprand1 + oprand2 / oprand3;
else if (op1 == '-' && op2 == '/')
oprand1 = oprand1 - oprand2 / oprand3;
op1 = op3;