4*4矩阵式键盘识别技术c语言程序,4×4矩阵式键盘识别技术

灰太狼 2022-10-15 01:58 132阅读 0赞

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

![201012817051143.gif][]

图4.14.1

2． 硬件电路原理图

![201012817051169.jpg][]

图4.14.2

3． 系统板上硬件连线

(1． 把“单片机系统“区域中的P3.0－P3.7端口用8芯排线连接到“4X4行列式键盘”区域中的C1－C4　R1－R4端口上；

(2． 把“单片机系统”区域中的P0.0/AD0－P0.7/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a－h端口上；要求：P0.0/AD0对应着a，P0.1/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

![201012817052426.gif][]

图4.14.3

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

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;

[201012817051143.gif]: /images/20221014/2dc7b3e3e737439da752ab228723480e.png
[201012817051169.jpg]: /images/20221014/27334a4207f44a8193d512b1487c130e.png
[201012817052426.gif]: /images/20221014/5faa324ffc96438db038b445cc80f816.png