51 single chip microcomputer key answering program

Download the header file STC12C5A.H:  http://www.51hei.com/mcu/2564.html

#include
#include "stdio.h"
#include "LCD1602.h"
#include "interrupt.h"
#include "chiclet_keyboard.h"
#define uchar unsigned char
#define uint unsigned int
void main()
{
 delay(500);
 LCD_init();
 interrupts_init();
 chiclet_keyboard_();
 EA=0;
 while(1);
}

#ifndef _LCD1602_H
#define _LCD1602_H
/*
MCU: STC89CXX, Crystal: 12M Compiler: KEIL uVision4 
LCD1602 Command Code:
 Code Description
 1 Clear display
 2 Cursor reset
Input mode selection:
 X 0000 01(I/D)S
   I/D: Cursor movement direction, 1 right, 0 left
   S: Whether the screen text moves. 1 move.
Display on/off control:
 X 0000 1DCB
   D: Overall display switch, 1 is on
   C: Cursor switch, 1 is on
   B: Cursor flashing, 1 is flashing
Cursor or character shift:
 X 0001 (S/C)(R/L)**
   S/C: 1 moves text, 0 moves cursor
   R/L: 1 is right, 0 is left
Function setting:
 X 001(DL) NF**
   DL: 1 is 8-line mode, 0 is 4-line mode
   N: 0 is single line display, 1 is 2 lines display
   F: 0 is 5X7 characters, 1 is 5X10 characters
Character address:
 X 01xx xxxx
   xxxxx: corresponding ASCII address
Display address:
 X 1xxx xxxx
   xxx xxxx: screen display address
Internal display and screen address correspondence note:
     00--0x0F corresponds to the first line of the screen, 00--0x27 internal first line
     0x40--0x4F corresponds to the second line of the screen, 0x40--0x67 internal second line
*/
#define uchar unsigned char
#define uint unsigned int 
//Define hardware interface
#define LCD_DATA P0
sbit LCD_EN=P2^5;
sbit LCD_RS=P2^3;
sbit LCD_RW=P2^4;
/**************************************************
Function name:
Function function:
Function call:
Input parameters:
Output parameters:
Copyright information:
Time version: V1.0
***************************************************/
/**************************************************
Function name: delay_ms(uint num)
Function function: delay
Function call:
Input parameter: msOutput
parameter:
Copyright information:
TimeVersion: V1.0Remarks
: Crystal: 12M
***************************************************/
void delay_ms(uint temp)
{
 uint x,y;
 for(x=temp;x>0;x--)
  for(y=110;y>0;y--);
}
/**************************************************
Function name: write_com(uchar com)
Function function: write command
Function call: delay_ms(uint num)
Input parameter: Command code
Output parameter:
Copyright information:
TimeVersion: V1.0
***********************************************/
void LCD_w_com(uchar com)
{
 LCD_RS=0;
 LCD_RW=0;
 LCD_DATA=com;
 delay_ms(5);
 LCD_EN=1;
 delay_ms(5);
 LCD_EN=0;
}[page]
/**********************************************
Function name: write_data(uchar date)
Function function: write data
Function call: delay_ms(uint num)
Input parameter: data
Output parameter:
copyright information:
time version: V1.0
***********************************************/
void LCD_w_data(uchar dat)
{
 LCD_RS=1;
 LCD_RW=0;
 LCD_DATA=dat;
 delay_ms(5);
 LCD_EN=1;
 delay_ms(5);
 LCD_EN=0;
}
/**********************************************
Function name:
Function function: LCD_init()
Function call: LCD_w_com()
Input parameter:
Output parameter:
Copyright information:
Time Version: V1.0
***************************************************/
void LCD_init()
{
 LCD_EN=0; 
 LCD_w_com(0x38); //8 lines, 2 rows, 5X7 character mode
 LCD_w_com(0x0c); //Display on, cursor not displayed, cursor not blinking
 LCD_w_com(0x06); //Cursor right move, text not moving
 LCD_w_com(0x01); //Clear display, cursor reset  
}
/**************************************************
Function name: LCD_disp_cher(uchar x,uchar y,uchar *p)
Function function: Display string at specified position
Function call: LCD_w_com(), LCD_w_data()
Input parameters: x, y coordinates, string pointer array
Output parameters:
Copyright information :
Time version: V1.0
Note: x is column, x<16, y is row, y<2. String length + x is not greater than 16.
***********************************************/
void LCD_disp_cher(uchar x,uchar y,uchar *p)
{
 if(y==1)
 {   
  LCD_w_com(0x80+x);
  while(*p)
  {
  LCD_w_data(*p);
  p++;
  }
 } 
 if(y==2)
 {    
  LCD_w_com(0x80+0x40+x);
  while(*p)
  {
  LCD_w_data(*p);
  p++;
  } 
 }
}
#endif//end LCD1602.H

#ifndef _interrupt_H_
#define _interrupt_H_
#define uint unsigned int
#define uchar unsigned char
uint sec=10;
sbit sb=P1^0;
sbit si=P1^1;
void interrupts_init()
{
 EA=1; //enable global interrupt
 ET0=1; //T0 (timer interrupt 0) overflow interrupt enable bit
 TR0=1; //0 run control bit
 TMOD=0x1; //16-bit timer  
 TH0=(65536-50000)/255;
 TL0=(65536-50000)%255; 
}
void ghjfgf() interrupt 1
{
 uint subtle;
 TH0=(65536-50000)/255; 
 TL0=(65536-50000)%255; 
 subtle++;
 if(subtle==20)
  {
   subtle=0;
   sec--;
  }
}
#endif

#ifndef _chiclet_keyboard_H_
#define _chiclet_keyboard_H_
sbit S1=P3^4; //Independent buttons S1~S4
sbit S2=P3^5;
sbit S3=P3^6;
sbit S4=P3^7; //Use the reset button to exit to save keystrokes
void delay(uint ms) //Delay
{
 uchar mus;
 for(ms; ms>0; ms--)
  for(mus=110; mus>0; mus--);
} 
uint chiclet_keyboard_() //The key detection subroutine has a return value for exiting the subroutine
{
 uchar dsa[10]; //Array for storing display
 while(1) //Detection infinite loop until a key is detected or the time is up sec=0;
 {
  if(S1==0)
  {
   delay(5);
   if(S1==0)
   {
    LCD_disp_cher(0,1," S1 "); //Display the key pressed first
    return 0;
   }
  }
  if(S2==0)
  {
   delay(5);
   if(S2==0)
   {
    LCD_disp_cher(0,1," S2 "); //Display the key pressed first
    return 0;
   }
  }
  if(S3==0)
  {
   delay(5);
   if(S3==0)
   {
    LCD_disp_cher(0,1," S3 "); //Display the key pressed first
    return 0;
   }
  }
  if(S4==0)
  {
   delay(5);
   if(S4==0)
   {
    LCD_disp_cher(0,1," S4 "); //Display the key pressed first
    return 0;
   }
  }
  if(sec==0) 
   {
    LCD_disp_cher(0,1," over time ");
    return 0;
   }
  sprintf(dsa," time %d ",sec); //Display time
  LCD_disp_cher(0,1,dsa);
 }
}
#endif