ex5-3.c

< 嵌入式C语言程序设计>>一书的源代码

/*
标题：范例 5-3
版本：1.0
Target：89S51
程序描述：这个范例说明如何使用8051的Port 1连接到LCD显示器，PORT 3的P3.3,P3.4和P3.5分别连接到LCD显示器的控制线程序执行时让LCD显示器显示出数字时钟PORT 2连接到4ⅹ4的小键盘,可以修改时间4ⅹ4小键盘的按钮B ,可以修改间*/
/* ***************************************************** */
#include <REGX51.H>
#include <lcd.h>
#define   TIMER0_COUNT 0xD8F0 /*10000h-((12,000,000/(12*100))*/
                             /* 数字时钟的工作模式 */
#define    SET          11
#define    TRUE         1
#define    FALSE        0
#define    putchar      write_LCD_data
typedef    struct { 
           char    hour;
           char    minute;
           char    second;
} time;
typedef    struct {
           char   year;
           char   month;
           char   day;
} date;
time now={23,59,0},display;
date today={04,05,29},tmpday;
static unsigned timer0_tick=100,mode=0,operation;
char code dayofmonth[]={31,28,31,30,31,30,31,31,30,31,30,31};
char code weekday[7][4]={"MON","TUE","WED","THU","FRI","SAT",
                         "SUN"};
char code command[1][6]={"Watch",};
char code int2char[]="0123456789";
char gotkey();
void display_time(void)
{
  gotoxy(1,0);
        display_LCD_number(display.hour);
        display_LCD_string(":");
        display_LCD_number(display.minute);
        display_LCD_string(":");
        display_LCD_number(display.second);
}
void display_date()
{
    char i,days=4;
  gotoxy(2,2);
        display_LCD_number(today.year);
        display_LCD_string("/");
        display_LCD_number(today.month);
        display_LCD_string("/");
        display_LCD_number(today.day);
        display_LCD_string(" ");
  if(today.month > 1)
        for(i=0;i<=today.month-2;i++)
            days+=(dayofmonth[i]%7);
        if( today.year !=0 ) days+=((today.year-1)/4)+today.year+1;
        if (today.year%4==0 && today.month >2) days++;
        days=(days+today.day) % 7;
        display_LCD_string(&weekday[days][0]);
  }
  int getdigit(unsigned char x,unsigned char y)
  {
        char  keys;
        do {
              gotoxy(x,y);
              putchar('_');
              keys=gotkey();
              gotoxy(x,y);
              putchar(int2char[keys]);
        } while(keys>9);
        return(keys);
  }
  int gettime()
  {
        char temp;
        do {
             while((temp=getdigit(1,0))>2);  //时的十位数不能大于2
             temp=temp*10+getdigit(1,1);
             if (temp > 23) display_time();
        } while (temp > 23);
        display.hour=temp;
          while((temp=getdigit(1,3))>5);
        display.minute=temp*10+getdigit(1,4); 
        return(TRUE);
  }
  char monthday(char year,char month)
  {
        if(month==2 && year%4==0)            //润年的2月有29天
             return(29);
        else
             return(dayofmonth[month-1]);    //非闰年时的该月份天数
  }
  int getdate()
  {
        char temp,days;
           temp=getdigit(2,2);
        tmpday.year=temp*10+getdigit(2,3); 
        do {
             while((temp=getdigit(2,5))>1);  //月的十位数不能大于1
             temp=temp*10+getdigit(2,6);
             if (temp > 12) display_date();  //月份的数字不能大于12
        } while (temp > 12);
        tmpday.month=temp;
        do {
             while((temp=getdigit(2,8))>3);  //日的十位数不能大于3
             temp=temp*10+getdigit(2,9);
             days=monthday(tmpday.year,tmpday.month);
               if(temp > days || temp==0) display_date();
        } while (temp > days || temp==0);
                                  //输入的日期大于该月日期就重新输入
          tmpday.day=temp;
          return(TRUE);
  }
  static void timer0_isr(void) interrupt  TF0_VECTOR using 1
  {
        TR0=0;
        TL0=(TIMER0_COUNT & 0x00FF);
        TH0=(TIMER0_COUNT >> 8);
        TR0=1;
        if(--timer0_tick) return;
        timer0_tick=100;
        now.second++;                         //秒加1
        if (now.second==60) {                 //如果秒等于60
                now.second=0;                 //秒恢复为0
                now.minute++;                 //分加1
                if (now.minute==60) {         //如果分等于60
                      now.minute=0;           //分恢复为0
                      now.hour++;             //时加1
                      if (now.hour==24) {     //如果时等于24
                            now.hour=0;       //时恢复为0
                            today.day++;      //日加1
                            if (today.day>monthday(today.year,
                                today.month)) {
                                  today.day=1;    
//如果日超过当月最大日数,就变成1
                                  today.month++;          
//月加1
                                  if(today.month==13) {   
//如果月等于13
                                       today.month=1;     
//月恢复为1
                                       today.year++;      
//年加1
                                  }
                             }
                             display_date();
                      }
                 }
         }
         if (operation==SET ) return;
         display=now;
         display_time();
}
static void timer0_initialize(void)
{
  EA=0;   
  TR0=0;
  TMOD &= 0XF0;
  TMOD |=0x01;
  TL0=(TIMER0_COUNT & 0x00FF);
  TH0=(TIMER0_COUNT >> 8);
  PT0=0;
  ET0=1;
  TR0=1;
  EA=1;
}
void main (void)  {
        char keys;
        init_LCD();
        clear_LCD();
        gotoxy(2,0);
        display_LCD_string("20");
        display=now;
        display_time();
        display_date();
        gotoxy(1,9);
        display_LCD_string(&command[mode][0]);
        timer0_initialize();
        do {
        keys=gotkey();
             if(keys==SET) {
                  operation=SET;
                  if ( gettime()) now=display;
                  if ( getdate()) {
                  today=tmpday;
                  display_date();
             }
        }
             operation=0;
        } while(1);
}