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第一章:硬件资源模块第二章:keilc软件使用
at89s51单片机实验及实践课题     at89s51单片机实验及实践课题
1.闪烁灯2.模拟开关灯
3.多路开关状态指示4.广告灯的左移右移
5.广告灯(利用取表方式)6.报警产生器
7.I/O并行口直接驱动LED显示8.按键识别方法之一
9.一键多功能按键识别技术10.00-99计数器
11.00-59秒计时器(软件延时)12.可预置可逆4位计数器
13.动态数码显示技术14.4×4矩阵式键盘识别技术
15.定时计数器T0作定时(一)16.定时计数器T0作定时应用技术(二)
17.99秒马表设计18.“嘀、嘀、……”报警声
19.“叮咚”门铃20.数字钟(★)
21.拉幕式数码显示技术22.电子琴
23.模拟计算器数字输入及显示24.8×8LED点阵显示技术
25.点阵LED“0-9”数字显示技术26.点阵式LED简单图形显示技术
27.ADC0809A/D转换器基本应用技术28.数字电压表
29.两点间温度控制30.四位数数字温度计
31.6位数显频率计数器32.电子密码锁设计
33.4×4键盘的电子密码锁34.带有存储器功能的数字温度计-DS1624技术应用
35.DS18B20数字温度计使用

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14.     4×4矩阵式键盘识别技术

1. 实验任务 如图4.14.2所示,用AT89S51的并行口P1接4×4矩阵键盘,以P1.0-P1.3作输入线,以P1.4-P1.7作输出线;在数码管上显示每个按键的“0-F”序号。对应的按键的序号排列如图4.14.1所示 3. 系统板上硬件连线

(1.       把“单片机系统“区域中的P3.0P3.7端口用8芯排线连接到“4X4行列式键盘”区域中的C1C4 R1R4端口上;

(2.       把“单片机系统”区域中的P0.0/AD0P0.7/AD7端口用8芯排线连接到“四路静态数码显示模块”区域中的任一个ah端口上;要求:P0.0/AD0对应着aP0.1/AD1对应着b……P0.7/AD7对应着h

4.  程序设计内容

(1.       4×4矩阵键盘识别处理

(2.       每个按键有它的行值和列值 ,行值和列值的组合就是识别这个按键的编码。矩阵的行线和列线分别通过两并行接口和CPU通信。每个按键的状态同样需变成数字量“0”和“1”,开关的一端(列线)通过电阻接VCC,而接地是通过程序输出数字“0”实现的。键盘处理程序的任务是:确定有无键按下,判断哪一个键按下,键的功能是什么;还要消除按键在闭合或断开时的抖动。两个并行口中,一个输出扫描码,使按键逐行动态接地,另一个并行口输入按键状态,由行扫描值和回馈信号共同形成键编码而识别按键,通过软件查表,查出该键的功能。

5.程序框图

6.汇编源程序

KEYBUF    EQU 30H

            ORG 00H

START:      MOV KEYBUF,#2

WAIT:  

            MOV P3,#0FFH

            CLR P3.4

            MOV A,P3

            ANL A,#0FH 

            XRL A,#0FH

            JZ NOKEY1

            LCALL DELY10MS

            MOV A,P3

            ANL A,#0FH

            XRL A,#0FH

            JZ NOKEY1

            MOV A,P3

            ANL A,#0FH

            CJNE A,#0EH,NK1

            MOV KEYBUF,#0

            LJMP DK1

NK1:        CJNE A,#0DH,NK2

            MOV KEYBUF,#1

            LJMP DK1

NK2:        CJNE A,#0BH,NK3

            MOV KEYBUF,#2

            LJMP DK1

NK3:        CJNE A,#07H,NK4

            MOV KEYBUF,#3

            LJMP DK1

NK4:        NOP

DK1:   

            MOV A,KEYBUF

            MOV DPTR,#TABLE

            MOVC A,@A+DPTR

            MOV P0,A

 

DK1A:       MOV A,P3

            ANL A,#0FH

            XRL A,#0FH

            JNZ DK1A

NOKEY1:

            MOV P3,#0FFH

            CLR P3.5

            MOV A,P3

            ANL A,#0FH

            XRL A,#0FH

            JZ NOKEY2

            LCALL DELY10MS

            MOV A,P3

            ANL A,#0FH

            XRL A,#0FH

            JZ NOKEY2

            MOV A,P3

            ANL A,#0FH

            CJNE A,#0EH,NK5

            MOV KEYBUF,#4

            LJMP DK2

NK5:        CJNE A,#0DH,NK6

            MOV KEYBUF,#5

            LJMP DK2

NK6:        CJNE A,#0BH,NK7

            MOV KEYBUF,#6

            LJMP DK2

NK7:        CJNE A,#07H,NK8

            MOV KEYBUF,#7

            LJMP DK2

NK8:        NOP

DK2:   

            MOV A,KEYBUF

            MOV DPTR,#TABLE

            MOVC A,@A+DPTR

            MOV P0,A

 

DK2A:       MOV A,P3

            ANL A,#0FH

            XRL A,#0FH

            JNZ DK2A

NOKEY2:

            MOV P3,#0FFH

            CLR P3.6

            MOV A,P3

            ANL A,#0FH

            XRL A,#0FH

            JZ NOKEY3

            LCALL DELY10MS

            MOV A,P3

            ANL A,#0FH

            XRL A,#0FH

            JZ NOKEY3

            MOV A,P3

            ANL A,#0FH

            CJNE A,#0EH,NK9

            MOV KEYBUF,#8

            LJMP DK3

NK9:        CJNE A,#0DH,NK10

            MOV KEYBUF,#9

            LJMP DK3

NK10:       CJNE A,#0BH,NK11

            MOV KEYBUF,#10

            LJMP DK3

NK11:       CJNE A,#07H,NK12

            MOV KEYBUF,#11

            LJMP DK3

NK12:       NOP

DK3:

            MOV A,KEYBUF

            MOV DPTR,#TABLE

            MOVC A,@A+DPTR

            MOV P0,A

 

DK3A:       MOV A,P3

            ANL A,#0FH

            XRL A,#0FH

            JNZ DK3A

NOKEY3:

            MOV P3,#0FFH

            CLR P3.7

            MOV A,P3

            ANL A,#0FH

            XRL A,#0FH

            JZ NOKEY4

            LCALL DELY10MS

            MOV A,P3

            ANL A,#0FH

            XRL A,#0FH

            JZ NOKEY4

            MOV A,P3

            ANL A,#0FH

            CJNE A,#0EH,NK13

            MOV KEYBUF,#12

            LJMP DK4

NK13:       CJNE A,#0DH,NK14

            MOV KEYBUF,#13

            LJMP DK4

NK14:       CJNE A,#0BH,NK15

            MOV KEYBUF,#14

            LJMP DK4

NK15:       CJNE A,#07H,NK16

            MOV KEYBUF,#15

            LJMP DK4

NK16:       NOP

DK4:   

            MOV A,KEYBUF

            MOV DPTR,#TABLE

            MOVC A,@A+DPTR

            MOV P0,A

 

DK4A:       MOV A,P3

            ANL A,#0FH

            XRL A,#0FH

            JNZ DK4A

NOKEY4:

            LJMP WAIT

DELY10MS:

            MOV R6,#10

D1:         MOV R7,#248

            DJNZ R7,$

            DJNZ R6,D1

            RET

TABLE:      DB 3FH,06H,5BH,4FH,66H,6DH,7DH,07H

            DB 7FH,6FH,77H,7CH,39H,5EH,79H,71H

            END

7.C语言源程序

#include <AT89X51.H>

unsigned char code table[]={0x3f,0x06,0x5b,0x4f,

                            0x66,0x6d,0x7d,0x07,

                            0x7f,0x6f,0x77,0x7c,

                            0x39,0x5e,0x79,0x71};

unsigned char temp;

unsigned char key;

unsigned char i,j;

 

 

void main(void)

{

  while(1)

    {

      P3=0xff;

      P3_4=0;

      temp=P3;

      temp=temp & 0x0f;

      if (temp!=0x0f)

        {

          for(i=50;i>0;i--)

          for(j=200;j>0;j--);

          temp=P3;

          temp=temp & 0x0f;

          if (temp!=0x0f)

            {

              temp=P3;

              temp=temp & 0x0f;             

              switch(temp)

                {

                  case 0x0e:

                    key=7;

                    break;

                  case 0x0d:

                    key=8;

                    break;

                  case 0x0b:

                    key=9;

                    break;

                  case 0x07:

                    key=10;

                    break;

                }

              temp=P3;

              P1_0=~P1_0;

              P0=table[key];

              temp=temp & 0x0f;             

              while(temp!=0x0f)

                {

                  temp=P3;

                  temp=temp & 0x0f;             

                }

            }

        }

 

      P3=0xff;

      P3_5=0;

      temp=P3;

      temp=temp & 0x0f;

      if (temp!=0x0f)

        {

          for(i=50;i>0;i--)

          for(j=200;j>0;j--);

          temp=P3;

          temp=temp & 0x0f;

          if (temp!=0x0f)

            {

              temp=P3;

              temp=temp & 0x0f;             

              switch(temp)

                {

                  case 0x0e:

                    key=4;

                    break;

                  case 0x0d:

                    key=5;

                    break;

                  case 0x0b:

                    key=6;

                    break;

                  case 0x07:

                    key=11;

                    break;

                }

              temp=P3;

              P1_0=~P1_0;

              P0=table[key];

              temp=temp & 0x0f;             

              while(temp!=0x0f)

                {

                  temp=P3;

                  temp=temp & 0x0f;             

                }

            }

        }

 

      P3=0xff;

      P3_6=0;

      temp=P3;

      temp=temp & 0x0f;

      if (temp!=0x0f)

        {

          for(i=50;i>0;i--)

          for(j=200;j>0;j--);

          temp=P3;

          temp=temp & 0x0f;

          if (temp!=0x0f)

            {

              temp=P3;

              temp=temp & 0x0f;             

              switch(temp)

                {

                  case 0x0e:

                    key=1;

                    break;

                  case 0x0d:

                    key=2;

                    break;

                  case 0x0b:

                    key=3;

                    break;

                  case 0x07:

                    key=12;

                    break;

                }

              temp=P3;

              P1_0=~P1_0;

              P0=table[key];

              temp=temp & 0x0f;             

              while(temp!=0x0f)

                {

                  temp=P3;

                  temp=temp & 0x0f;             

                }

            }

        }

 

      P3=0xff;

      P3_7=0;

      temp=P3;

      temp=temp & 0x0f;

      if (temp!=0x0f)

        {

          for(i=50;i>0;i--)

          for(j=200;j>0;j--);

          temp=P3;

          temp=temp & 0x0f;

          if (temp!=0x0f)

            {

              temp=P3;

              temp=temp & 0x0f;             

              switch(temp)

                {

                  case 0x0e:

                    key=0;

                    break;

                  case 0x0d:

                    key=13;

                    break;

                  case 0x0b:

                    key=14;

                    break;

                  case 0x07:

                    key=15;

                    break;

                }

              temp=P3;

              P1_0=~P1_0;

              P0=table[key];

              temp=temp & 0x0f;             

              while(temp!=0x0f)

                {

                  temp=P3;

                  temp=temp & 0x0f;             

                }

            }

        }

    }

}