51 single chip microcomputer digital tube and matrix keyboard

Use 4*4 's matrix keyboard and a digital tube

Encode 0-f characters on the 4*4 matrix keyboard, and a digital tube to display the characters entered on each keyboard.

4*4 keyboard Detection program, press the key after the corresponding code displayed in the digital tube #include<reg51.h>typedef unsigned char UINT8; UINT8 i=100; UINT8 j,k,temp,key;void Delay (unsigned char i) {for (j=i;j>0;j--) for (k=125;k>0;k--);} UINT8 Code table[]={0x3f,0x06,0x5b,0x4f,0x66,0x6d,0x7d,0x07,0x7f,0x6f,0x77,0x7c,0x39,0x5e,0x79,0x71};void Display (unsigned char num) {P0=table[num];}                                                                                                     void init_led () {P0 = 0x00;} void Main () {while (1) {P1 = 0xef;temp = P1;temp = Temp&0xf0;if (temp! = 0xf0) {temp = P1;switch (temp) {case 0xe   e:key=0;  Break   Case 0xed:key=1;  Break   Case 0xeb:key=2;  Break   Case 0xe7:key=3;  Break Default:break;} Display (key); P1=0xfe;}   P1 = 0xdf;temp = P1;temp = Temp&0x0f;if (temp! = 0x0f) {temp = P1;switch (temp) {Case 0xde:key = 4;  Break   Case 0xdd:key = 5;  Break   Case 0xdb:key = 6;  Break   Case 0xd7:key = 7;  Break Default:break; } display (key);} p1=0xbf;temp=p1;temp=Temp&0x0f;if (temp! = 0x0f) {Temp=p1;switch (temp) {case 0xbe:key=8;  Break   Case 0xbd:key=9;  Break   Case 0xbb:key=10;  Break   Case 0xb7:key=11;  Break Default:break;} Display (key);}   P1=0x7f;temp=p1;temp=temp&0x0f;if (temp!=0x0f) {Temp=p1;switch (temp) {case 0x7e:key=12;  Break   Case 0x7d:key=13;  Break   Case 0x7b:key=14;  Break   Case 0x77:key=15;    Break Default:break;} Display (key);}}}

This has a bug that every time you enter the digital tube is not empty but the reality of "0" this is not resolved.

51 single chip microcomputer digital tube and matrix keyboard