/*******************************************************************/
/***部分內容抄自：ME300B單片機開發系統演示程序?-?矩陣鍵盤鍵值顯示***/??
/*******************************************************************/

#include?
#include?

sbit?BEEP?=?P3^7;??????????//蜂鳴器
unsigned?char??dis_buf;????//顯示緩存
unsigned?char?addr;????????//lcd?顯示地址
unsigned?char?m;
unsigned?char?data?n;?
unsigned?char?data?k;

void?beep（）;???????????????//蜂鳴器
void?delay0（unsigned?char?x）;??????//x*0.14MS
void?cleansec（）;
void??keydown（void）;
void?addi（void）;????//加法
void?subt（void）;????//減法
void?mult（void）;????//乘法
void?divi（void）;????//除法

sbit?LCD_RS?=?P2^0;?????????????
sbit?LCD_RW?=?P2^1;
sbit?LCD_EN?=?P2^2;

unsigned?char?code??cdis1[?]?=?{“?A?&?B??=?RESULT“};
unsigned?char?code??cdis2[?]?=?{“????????????????“};
unsigned?char?data??front[]?=?{000};
unsigned?char?data??back[?]?=?{000};
unsigned?char?code?result[?]?=?{“000000“};

/*************************************************************/
/*???????????????????????????????????????????????????????????*/
/*?延時子程序????????????????????????????????????????????????*/
/*???????????????????????????????????????????????????????????*/
/*************************************************************/
void??delay（unsigned?char?x）
{?unsigned?char?j;
????while（x--）
????{?for（j=0;j<125;j++）;
????}
}

/*************************************************************/
/*???????????????????????????????????????????????????????????*/
/*檢查LCD忙狀態??????????????????????????????????????????????*/
/*lcd_busy為1時，忙，等待。lcd-busy為0時閑，可寫指令與數據??*/
/*???????????????????????????????????????????????????????????*/
/*************************************************************/?
bit?lcd_busy（）
?{??????????????????????????
????bit?result;
????LCD_RS?=?0;
????LCD_RW?=?1;
????LCD_EN?=?1;
????_nop_（）;
????result?=?（bit）（P0&0x80）;
????LCD_EN?=?0;
????return（result）;?
?}

/*******************************************************************/
/*?????????????????????????????????????????????????????????????????*/
/*寫指令數據到LCD??????????????????????????????????????????????????*/
/*RS=L，RW=L，E=高脈沖，D0-D7=指令碼。?????????????????????????????*/
/*?????????????????????????????????????????????????????????????????*/
/*******************************************************************/
void?lcd_wcmd（unsigned?char?cmd）
{??????????????????????????
???while（lcd_busy（））;
????LCD_RS?=?0;
????LCD_RW?=?0;
????LCD_EN?=?0;
????_nop_（）;
????_nop_（）;?
????P0?=?cmd;
????_nop_（）;
????LCD_EN?=?1;
????_nop_（）;
????LCD_EN?=?0;??
}

/*******************************************************************/
/*?????????????????????????????????????????????????????????????????*/
/*寫顯示數據到LCD??????????????????????????????????????????????????*/
/*RS=H，RW=L，E=高脈沖，D0-D7=數據。???????????????????????????????*/
/*?????????????????????????????????????????????????????????????????*/
/*****************************************************

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件??????26550??2006-08-11?16:25??計算器\count

?????文件??????15770??2009-06-18?19:36??計算器\count.c

?????文件??????13115??2006-08-11?16:25??計算器\count.hex

?????文件??????26700??2006-08-11?16:25??計算器\count.LST

?????文件??????30048??2006-08-11?16:25??計算器\count.M51

?????文件??????30922??2006-08-11?16:25??計算器\count.OBJ

?????文件???????1080??2006-08-11?21:43??計算器\count.Opt

?????文件????????154??2006-08-11?21:43??計算器\count.plg

?????文件???????2055??2006-08-11?16:25??計算器\count.Uv2

?????文件???????1092??2006-08-11?16:25??計算器\count_Opt.Bak

?????文件??????????0??2006-08-11?16:13??計算器\count_Uv2.Bak

?????文件???????5115??2002-04-16?15:32??計算器\STARTUP.A51

?????文件??????11754??2006-08-11?16:25??計算器\STARTUP.lst

?????文件????????834??2006-08-11?16:25??計算器\STARTUP.obj

?????目錄??????????0??2009-05-11?00:04??計算器

-----------?---------??----------?-----??----

???????????????165189????????????????????15