51单片机Protues，仿真计算器，可以实现加减乘除正余弦正切Ln的求解，并在LCD1602液晶上显示结果。程序+仿真

#include<reg52.h> #include<math.h> #define unchar unsigned char #define unint unsigned int #define Pi 3.141596 sbit rs=P2^0; sbit rw=P2^1; sbit en=P2^2; sbit busy=P0^7; char i,j,flag,fuhao,y,r,z; char s[30]; unchar num,temp; long a,b,c; unchar code table[]={7,8,9,0,//内部运算用 4,5,6,0, 1,2,3,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0}; unchar code table1[]={7,8,9,0x2f-0x30,//显示用7，8，9，/,//后面加了0x30，所以这里减掉 4,5,6,0x2a-0x30,//4,5,6,* 1,2,3,0x2d-0x30,//1,2,3,- 0x01-0x30,0,0x3d-0x30,0x2b-0x30,//ON/C,0,=,+ 0x22-0x30,0x5e-0x30,0x25-0x30,0x21-0x30,//"代表根号，^次方，%，！ 0x02-0x30,0x03-0x30,0x04-0x30,//2转10，10转2，10转16，16转10 0x05-0x30,0x06-0x30,0x07-0x30,0x08-0x30};//sin,coa,tan,ln void delay(unchar z) { unchar x,y; for(x=z;x>0;x--) for(y=110;y>0;y--); } void checkbusy() { while(busy==1)//P0^7最高位为1为忙，0为闲 { P0=0xff; rs=0; rw=1; en=0;//禁止读写 delay(20); en=1; } } void write_com(unchar com) { rs=0; rw=0; en=0; checkbusy(); P0=com; delay(5); en=1; delay(5); en=0; } void write_date(unchar date) { rs=1; rw=0; en=0; checkbusy(); P0=date; delay(5); en=1; delay(5); en=0; } void init() { write_com(0x38);//16*2显示，5*7点阵，8位数据接口 delay(50); write_com(0x0c);//开显示关光标和闪烁 delay(50); write_com(0x06);//地址向后移 delay(50); write_com(0x80);//光标初始地址 write_com(0x01);//清屏 delay(50); i=0;flag=0;//赋初值flag表示按符号键后的输入值，默认为没按之前的输入 fuhao=0;a=0;b=0;c=0; } void lcd_clean()//清屏 { write_com(0x01); delay(20); } void keyscan() { //**************P3口的键盘检测 P3=0xfe; temp=P3; temp=temp&0xf0; if(temp!=0xf0) { delay(10); temp=P3; temp=temp&0xf0; if(temp!=0xf0) { temp=P3; switch(temp) { case 0xee:num=0; break; case 0xde:num=1; break; case 0xbe:num=2; break; case 0x7e:num=3; break; } } while(P3!=0xfe); if(num==0||num==1||num==2) { if(flag==0) a=a*10+table[num];//a是在没按符号键之前输入的值 if(flag==1) b=b*10+table[num];//b是按符号键后输入的值 } if(num==3)//"/"除键 { flag=1; fuhao=4;//"/" } i=table1[num];//显示的值 write_date(0x30+i);//十六进制表示的ASC码 } P3=0xfd; temp=P3; temp=temp&0xf0; if(temp!=0xf0) { delay(5); temp=P3; temp=temp&0xf0; if(temp!=0xf0) { temp=P3; switch(temp) { case 0xed:num=4; break; case 0xdd:num=5; break; case 0xbd:num=6; break; case 0x7d:num=7; break; } } while(P3!=0xfd); if(num==4||num==5||num==6) { if(flag==0) a=a*10+table[num]; else b=b*10+table[num]; } if(num==7)//"*"乘 { flag=1; fuhao=3; } i=table1[num]; write_date(0x30+i); } P3=0xfb; temp=P3; temp=temp&0xf0; if(temp!=0xf0) { delay(5); temp=P3; temp=temp&0xf0; if(temp!=0xf0) { temp=P3; switch(temp) { case 0xeb:num=8; break; case 0xdb:num=9; break; case 0xbb:num=10; break; case 0x7b:num=11; break; } } while(P3!=0xfb); if(num==8||num==9||num==10) { if(flag==0) {a=a*10+table[num];} else {b=b*10+table[num];} } if(num==11)//"-"减 { flag=1; fuhao=2; } i=table1[num]; write_date(0x30+i); } P3=0xf7; temp=P3; temp=temp&0xf0; if(temp!=0xf0) { delay(5); temp=P3; temp=temp&0xf0; if(temp!=0xf0) { temp=P3; switch(temp) { case 0xe7:num=12; break; case 0xd7:num=13; break; case 0xb7:num=14; break; case 0x77:num=15; break; } } while(P3!=0xf7);//松手检测，没有松手则保持显示的状态 switch(num) { case 12:{ lcd_clean(); a=0;b=0;flag=0; fuhao=0; } break; case 13:{ if(flag==0) { a=a*10;write_date(0x30); } else { b=b*10; write_date(0x30); } } break; case 14:{//需要按"="的 if(fuhao==1) { write_com(0x80+0x0f); lcd_clean();//重新定位后再清屏 write_com(0x04); i=0; c=a+b; while(c!=0) { write_date(0x30+c%10); c=c/10; } write_date(0x3d);//写"=" a=0;b=0;flag=0;fuhao=0;//清0 } else if(fuhao==2) { write_com(0x80+0x0f); lcd_clean(); write_com(0x04); if(a-b>0) c=a-b; else c=b-a; while(c!=0) { write_date(0x30+c%10); c=c/10; } if(a-b<0) write_date(0x2d);//"-"减 write_date(0x3d); a=0;b=0;flag=0;fuhao=0; } else if(fuhao==3) { write_com(0x80+0x0f); lcd_clean(); write_com(0x04); c=a*b; while(c!=0) { write_date(0x30+c%10); c=c/10; } write_date(0x3d); a=0;b=0;flag=0;fuhao=0; } else if(fuhao==4) { write_com(0x80+0x0f); lcd_clean(); write_com(0x04); i=0; c=(long)(((float)a/b)*1000);//化整后再加小数点 while(c!=0) { write_date(0x30+c%10); c=c/10; i++; if(i==3) write_date(0x2e);//加小数点"." } if(a/b<=0) write_date(0x30); write_date(0x3d); a=0;b=0;flag=0;fuhao=0; } else if(fuhao==5) { write_com(0x80+0x0f); lcd_clean(); write_com(0x04); c=(long)(pow((float)a,(float)1/b)*1000); i=0; while(c!=0) { write_date(0x30+c%10); c=c/10; i++; if(i==3) write_date(0x2e); } write_date(0x3d); a=0;b=0;flag=0;fuhao=0; } else if(fuhao==6) { write_com(0x80+0x0f); lcd_clean(); write_com(0x04); c=pow((float)a,(float)b);//c52内部的函数 while(c!=0) { write_date(0x30+c%10); c=c/10; } write_date(0x3d); a=0;b=0;flag=0;fuhao=0; } else if(fuhao==7) { write_com(0x80+0x0f); lcd_clean(); write_com(0x04); c=a%b; if(c==0) write_date(0x30); while(c>0) { write_date(0x30+c%10); c=c/10; } write_date(0x3d); a=0;b=0;flag=0;fuhao=0; } } break; case 15:{ i=table1[num]; write_date(0x30+i);//"+"加 flag=1;fuhao=1; } break; } } //*********************P1口的键盘检测 P1=0xfe; temp=P1; temp=temp&0xf0; if(temp!=0xf0) { delay(5); temp=P1; temp=temp&0xf0; if(temp!=0xf0) { temp=P1; switch(temp) { case 0xee:num=16; break; case 0xde:num=17; break; case 0xbe:num=18; break; case 0x7e:num=19; break; } } while(P1!=0xfe); switch(num) { case 16:{ i=table1[num]; write_da