电子时钟设计实验报告

1、 单片机电子时钟设计报告1、 设计任务 本次课程设计的电子时钟电路，是基于单片机stc89c52、时钟芯片和液晶显示，运用c语言编程实现。电子时钟可以显示日期的年、月、日和时间的时、分、秒，具有复位功能。2、 系统硬件设备及芯片简介 数字电子钟系统设计已经成熟，但是目前系统设计时基本 都是采用 led 作为显示电路，造成硬件电路复杂、功耗高、产 品体积庞大等特点；液晶显示模块由于具有低功耗、寿命长、 体积小、显示内容丰富、价格低、接口控制方便等优点，因此 在各类电子产品中被极广泛地推广和应用。字符型液晶显示模 块是一类专门用于显示字母、数字、符号等点阵式液晶显示模 块。本系统设计采用字符型液品

2、显示模块 lcd1602 作为显示器 件，这样不仅简化了系统的硬件设计，而且极大地提高了系统 的可靠性。1lcd1602 简介字符型液晶显示模块 lcd1602 已经是单片机应用设计中 最常用的信息显示器件。lcd1602 可以显示两行，每行 16 个 字符，采用5v 电源供电，外围电路配置简单，价格便宜，具 有很高的性价比。2lcd1602 功能介绍2.1 引脚功能lcd1602 采用标准 14 脚（无背光）或 16 脚（带背光）接口，各引脚功能见表 1。表 1 引脚功能编号符号引脚说明编号符号引脚说明1vss电源地9d2data i/o2vdd电源正极10d3data i/o3vl液晶显示

3、偏压信号11d4data i/o4rs数据/命令选择端12d5data i/o5r/w读/写选择端13d6data i/o6e使能信号14d7data i/o7d0data i/o15bla背光源正极8d1data i/o16blk背光源负极2.2 lcd1602 读写指令lcd1602 读写指令较多且较复杂，具体使用可以查相关资料，下面仅列出最常用的的一些命令：写指令 38h：显示模式设置；写指令 08h：显示关闭；写指令 01h：显示清屏；写指令 06h：显示光标移动设置；写指令 0ch：显示开及光标设置。2.3 lcd1602 读写操作时序lcd1602 读写操作时序总体上来说是比较简单

4、的，掌握其有两种方法：一种是只看时序图，另外一种方法是直接记忆和总结读写时电平高低和变化。很显然第二种更简单和直接，下面就列出典型读写的时序要求，以方便编写程序。（1） 读状态：输入：rsl，rwh，eh。 输出：d0d7状态字。（2） 写指令：输入：rsl,rwl,d0d7指令码，e上升沿。输出：无。（3）读数据：输入：rsh，rwh，eh。输出：d0d7数据。（4）写 数 据：输入：rsh,rwl,d0d7数据，e上升沿。输出：无。2.4 lcd1602 显示方法液晶显示模块是慢速显示器件，所以在执行每条指令之前一定要确认模块的忙标志为低电平（即不忙），否则该指令失效。显示字符时，要先输入

5、显示字符地址，即告诉模块在哪里显示字符。因为写入显示地址时要求最高位 d7 恒定为高电平，所以实际写入的数据应该是要显示地址值加上 80h，即将最高位 d7 置为 1。在使用此显示模块时一般要对其进行初始化，设置所需要的显示参数。液晶模块在显示字符时光标是自动右移的，无需人工干预。每次输入指令前，都要判断液晶模块是否处于忙状态。3数字电子钟硬件电路设计硬件电路系统设计主要由单片机最小系统、输入电路、输 出电路等组成。单片机最小系统同所有单片机系统，在此不作 讨论。输入电路主要时间调节电路，为简化系统我们使两个外 部中断来调节“时”和“分”数值，即将 int0、int1 分别接 两个按钮。lcd

6、 显示器和单片机接口电路可以采用总线方式或 者是模拟口线方式，本设计采用第二种方式，即以单片机 i/o 模拟控制信号。具体电路见图 1，p0 口作为数据，并接上拉电 阻提升电压，p2.0 接 lcd 的 rs 端、p2.1 接 lcd 的 r/w 端、 p2.2 接 lcd 的 e 端，“分”调节按钮接 int0，“时”调节按钮 接 int1，图 1 省略了电源和单片机最小系统电路。图 1 数字电子钟硬件电路 3、 设计电路图及程序1. 电路图如下原理图如下：2. 程序共有四段程序，用keil仿真是程序列表如图regx52.h程序为：#ifndef _at89x52_h_#define _at

7、89x52_h_sfr p0 = 0x80;sfr sp = 0x81;sfr dpl = 0x82;sfr dph = 0x83;sfr pcon = 0x87;sfr tcon = 0x88;sfr tmod = 0x89;sfr tl0 = 0x8a;sfr tl1 = 0x8b;sfr th0 = 0x8c;sfr th1 = 0x8d;sfr p1 = 0x90;sfr scon = 0x98;sfr sbuf = 0x99;sfr p2 = 0xa0;sfr ie = 0xa8;sfr p3 = 0xb0;sfr ip = 0xb8;sfr t2con = 0xc8;sfr t2m

8、od = 0xc9;sfr rcap2l = 0xca;sfr rcap2h = 0xcb;sfr tl2 = 0xcc;sfr th2 = 0xcd;sfr psw = 0xd0;sfr acc = 0xe0;sfr b = 0xf0;/*-p0 bit registers-*/sbit p0_0 = 0x80;sbit p0_1 = 0x81;sbit p0_2 = 0x82;sbit p0_3 = 0x83;sbit p0_4 = 0x84;sbit p0_5 = 0x85;sbit p0_6 = 0x86;sbit p0_7 = 0x87;/*-pcon bit values-*/#d

9、efine idl_ 0x01#define stop_ 0x02#define pd_ 0x02 /* alternate definition */#define gf0_ 0x04#define gf1_ 0x08#define smod_ 0x80/*-tcon bit registers-*/sbit it0 = 0x88;sbit ie0 = 0x89;sbit it1 = 0x8a;sbit ie1 = 0x8b;sbit tr0 = 0x8c;sbit tf0 = 0x8d;sbit tr1 = 0x8e;sbit tf1 = 0x8f;/*-tmod bit values-*

10、/#define t0_m0_ 0x01#define t0_m1_ 0x02#define t0_ct_ 0x04#define t0_gate_ 0x08#define t1_m0_ 0x10#define t1_m1_ 0x20#define t1_ct_ 0x40#define t1_gate_ 0x80#define t1_mask_ 0xf0#define t0_mask_ 0x0f/*-p1 bit registers-*/sbit p1_0 = 0x90;sbit p1_1 = 0x91;sbit p1_2 = 0x92;sbit p1_3 = 0x93;sbit p1_4 =

11、 0x94;sbit p1_5 = 0x95;sbit p1_6 = 0x96;sbit p1_7 = 0x97;sbit t2 = 0x90; /* external input to timer/counter 2, clock out */sbit t2ex = 0x91; /* timer/counter 2 capture/reload trigger & dir ctl */*-scon bit registers-*/sbit ri = 0x98;sbit ti = 0x99;sbit rb8 = 0x9a;sbit tb8 = 0x9b;sbit ren = 0x9c;sbit

12、 sm2 = 0x9d;sbit sm1 = 0x9e;sbit sm0 = 0x9f;/*-p2 bit registers-*/sbit p2_0 = 0xa0;sbit p2_1 = 0xa1;sbit p2_2 = 0xa2;sbit p2_3 = 0xa3;sbit p2_4 = 0xa4;sbit p2_5 = 0xa5;sbit p2_6 = 0xa6;sbit p2_7 = 0xa7;/*-ie bit registers-*/sbit ex0 = 0xa8; /* 1=enable external interrupt 0 */sbit et0 = 0xa9; /* 1=en

13、able timer 0 interrupt */sbit ex1 = 0xaa; /* 1=enable external interrupt 1 */sbit et1 = 0xab; /* 1=enable timer 1 interrupt */sbit es = 0xac; /* 1=enable serial port interrupt */sbit et2 = 0xad; /* 1=enable timer 2 interrupt */sbit ea = 0xaf; /* 0=disable all interrupts */*-p3 bit registers (mnemoni

14、cs & ports)-*/sbit p3_0 = 0xb0;sbit p3_1 = 0xb1;sbit p3_2 = 0xb2;sbit p3_3 = 0xb3;sbit p3_4 = 0xb4;sbit p3_5 = 0xb5;sbit p3_6 = 0xb6;sbit p3_7 = 0xb7;sbit rxd = 0xb0; /* serial data input */sbit txd = 0xb1; /* serial data output */sbit int0 = 0xb2; /* external interrupt 0 */sbit int1 = 0xb3; /* exte

15、rnal interrupt 1 */sbit t0 = 0xb4; /* timer 0 external input */sbit t1 = 0xb5; /* timer 1 external input */sbit wr = 0xb6; /* external data memory write strobe */sbit rd = 0xb7; /* external data memory read strobe */*-ip bit registers-*/sbit px0 = 0xb8;sbit pt0 = 0xb9;sbit px1 = 0xba;sbit pt1 = 0xbb

16、;sbit ps = 0xbc;sbit pt2 = 0xbd;/*-t2con bit registers-*/sbit cp_rl2= 0xc8; /* 0=reload, 1=capture select */sbit c_t2 = 0xc9; /* 0=timer, 1=counter */sbit tr2 = 0xca; /* 0=stop timer, 1=start timer */sbit exen2= 0xcb; /* timer 2 external enable */sbit tclk = 0xcc; /* 0=serial clock uses timer 1 over

17、flow, 1=timer 2 */sbit rclk = 0xcd; /* 0=serial clock uses timer 1 overflow, 1=timer 2 */sbit exf2 = 0xce; /* timer 2 external flag */sbit tf2 = 0xcf; /* timer 2 overflow flag */*-t2mod bit values-*/#define dcen_ 0x01 /* 1=timer 2 can be configured as up/down counter */#define t2oe_ 0x02 /* timer 2

18、output enable */*-psw bit registers-*/sbit p = 0xd0;sbit fl = 0xd1;sbit ov = 0xd2;sbit rs0 = 0xd3;sbit rs1 = 0xd4;sbit f0 = 0xd5;sbit ac = 0xd6;sbit cy = 0xd7;/*-interrupt vectors:interrupt address = (number * 8) + 3-*/#define ie0_vector0 /* 0x03 external interrupt 0 */#define tf0_vector1 /* 0x0b ti

19、mer 0 */#define ie1_vector2 /* 0x13 external interrupt 1 */#define tf1_vector3 /* 0x1b timer 1 */#define sio_vector4 /* 0x23 serial port */#define tf2_vector5 /* 0x2b timer 2 */#define ex2_vector5 /* 0x2b external interrupt 2 */#endiflcd1602驱动程序为：#ifndef lcd_char_1602_2005_4_9#define lcd_char_1602_2

20、005_4_9#include /port definitions*sbit lcdrs= p20;sbit lcdrw= p21;sbit lcden = p22;sfr dbport = 0x80;/p0=0x80,p1=0x90,p2=0xa0,p3=0xb0.数据端口/内部等待函数*unsigned char lcd_wait(void)lcdrs=0;lcdrw=1;_nop_();lcden=1;_nop_();/while(dbport&0x80);/在用proteus仿真时，注意用屏蔽此语句，在调用gotoxy()时，会进入死循环， /可能在写该控制字时，该模块没有返回写入完备

21、命令，即dbport&0x80=0x80 /实际硬件时打开此语句lcden=0;return dbport;/向lcd写入命令或数据*#define lcd_command0 / command#define lcd_data1 / data#define lcd_clear_screen0x01 / 清屏#define lcd_homing 0x02 / 光标返回原点void lcd_write(bit style, unsigned char input)lcden=0;lcdrs=style;lcdrw=0;_nop_();dbport=input;_nop_();/注意顺序lcden=

22、1;_nop_();/注意顺序lcden=0;_nop_();lcd_wait();/设置显示模式*#define lcd_show0x04 /显示开#define lcd_hide0x00 /显示关 #define lcd_cursor0x02 /显示光标#define lcd_no_cursor0x00 /无光标 #define lcd_flash0x01 /光标闪动#define lcd_no_flash0x00 /光标不闪动void lcd_setdisplay(unsigned char displaymode)lcd_write(lcd_command, 0x08|displaym

23、ode);/设置输入模式*#define lcd_ac_up0x02#define lcd_ac_down0x00 / default#define lcd_move0x01 / 画面可平移#define lcd_no_move0x00 /defaultvoid lcd_setinput(unsigned char inputmode)lcd_write(lcd_command, 0x04|inputmode);/移动光标或屏幕*/*#define lcd_cursor0x02 #define lcd_screen0x08#define lcd_left0x00#define lcd_righ

24、t0x04void lcd_move(unsigned char object, unsigned char direction)if(object=lcd_cursor)lcd_write(lcd_command,0x10|direction);if(object=lcd_screen)lcd_write(lcd_command,0x18|direction);*/初始化lcd*void lcd_initial()lcden=0;lcd_write(lcd_command,0x38); /8位数据端口,2行显示,5*7点阵lcd_write(lcd_command,0x38);lcd_set

25、display(lcd_show|lcd_no_cursor); /开启显示, 无光标lcd_write(lcd_command,lcd_clear_screen); /清屏lcd_setinput(lcd_ac_up|lcd_no_move); /ac递增, 画面不动/*void gotoxy(unsigned char x, unsigned char y)if(y=0)lcd_write(lcd_command,0x80|x);if(y=1)lcd_write(lcd_command,0x80|(x-0x40);void print(unsigned char *str)while(*s

26、tr!=0)lcd_write(lcd_data,*str);str+;/*void lcd_loadchar(unsigned char user8, unsigned char place)unsigned char i;lcd_write(lcd_command,0x40|(place*8);for(i=0; i0; i-) ds1302_io = acc0; /相当于汇编中的 rrc ds1302_clk = 1; ds1302_clk = 0; acc = acc 1; unsigned char ds1302outputbyte(void) /实时时钟读取一字节(内部函数) uns

27、igned char i; for(i=8; i0; i-) acc = acc 1; /相当于汇编中的 rrc acc7 = ds1302_io; ds1302_clk = 1; ds1302_clk = 0; return(acc); void write1302(unsigned char ucaddr, unsigned char ucda)/ucaddr: ds1302地址, ucdata: 要写的数据 ds1302_rst = 0; ds1302_clk = 0; ds1302_rst = 1; ds1302inputbyte(ucaddr); / 地址，命令 ds1302inpu

28、tbyte(ucda); / 写1byte数据 ds1302_clk = 1; ds1302_rst = 0; unsigned char read1302(unsigned char ucaddr)/读取ds1302某地址的数据 unsigned char ucdata; ds1302_rst = 0; ds1302_clk = 0; ds1302_rst = 1; ds1302inputbyte(ucaddr|0x01); / 地址，命令 ucdata = ds1302outputbyte(); / 读1byte数据 ds1302_clk = 1; ds1302_rst = 0; retu

29、rn(ucdata);void ds1302_setprotect(bit flag) /是否写保护if(flag)write1302(0x8e,0x10);elsewrite1302(0x8e,0x00);void ds1302_settime(unsigned char address, unsigned char value) / 设置时间函数ds1302_setprotect(0);write1302(address, (value/10)second = (readvalue&0x70)4)*10 + (readvalue&0x0f);readvalue = read1302(ds1

30、302_minute);time-minute = (readvalue&0x70)4)*10 + (readvalue&0x0f);readvalue = read1302(ds1302_hour);time-hour = (readvalue&0x70)4)*10 + (readvalue&0x0f);readvalue = read1302(ds1302_day);time-day = (readvalue&0x70)4)*10 + (readvalue&0x0f);readvalue = read1302(ds1302_week);time-week = (readvalue&0x70

31、)4)*10 + (readvalue&0x0f);readvalue = read1302(ds1302_month);time-month = (readvalue&0x70)4)*10 + (readvalue&0x0f);readvalue = read1302(ds1302_year);time-year = (readvalue&0x70)4)*10 + (readvalue&0x0f);void datetostr(systemtime *time)time-datestring0 = time-year/10 + 0;time-datestring1 = time-year%1

32、0 + 0;time-datestring2 = -;time-datestring3 = time-month/10 + 0;time-datestring4 = time-month%10 + 0;time-datestring5 = -;time-datestring6 = time-day/10 + 0;time-datestring7 = time-day%10 + 0;time-datestring8 = 0;void timetostr(systemtime *time)time-timestring0 = time-hour/10 + 0;time-timestring1 =

33、time-hour%10 + 0;time-timestring2 = :;time-timestring3 = time-minute/10 + 0;time-timestring4 = time-minute%10 + 0;time-timestring5 = :;time-timestring6 = time-second/10 + 0;time-timestring7 = time-second%10 + 0;time-datestring8 = 0;void initial_ds1302(void)unsigned char second=read1302(ds1302_second);if(second&0x80) ds1302_settime(ds1302_seco