弄清楚类比于手机锁屏密码的模式，使用Arduino利用4*4矩阵键盘来实现输入密码功能，利用EEPROM实现保存密码功能。
本次完成的内容需要的材料：
Arduino UNO
一块4*4矩阵键盘
一个LED灯
导线（若干）
线路图：
实验所用的代码：
/* @file CustomKeypad.pde
|| @version 1.0
|| @author Alexander Brevig
|| @contact alexanderbrevig@gmail.com
||
|| @description
|| | Demonstrates changing the keypad size and key values.
|| #
*/
#include "Keypad.h"
#include <EEPROM.h>
const byte ROWS = 4; //four rows
const byte COLS = 4; //four columns
//define the cymbols on the buttons of the keypads
char hexaKeys[ROWS][COLS] = {
{'1','2','3','A'},
{'4','5','6','B'},
{'7','8','9','C'},
{'*','0','#','D'}
};
byte rowPins[ROWS] = {9, 8, 7, 6}; //connect to the row pinouts of the keypad
byte colPins[COLS] = {5, 4, 3, 2}; //connect to the column pinouts of the keypad
//initialize an instance of class NewKeypad
Keypad customKeypad = Keypad( makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS);
int pass;
void setup(){
Serial.begin(115200);
pinMode(13,OUTPUT);
pass = EEPROM.read(0);
Serial.println(pass);
delay(500);
}
void loop(){
char customKey = customKeypad.getKey();
if (customKey){
Serial.println(customKey);
digitalWrite(13, LOW);
}
if(customKey == 'A')
{
int a,b,c,d,q,i=0;
while(1)
{
char customKey = customKeypad.getKey();
if (customKey){
Serial.println(customKey);
}
if(i == 0&&customKey&&customKey!='#')
a = (int)(customKey)-48;
if(i == 1&&customKey)
{
b = (int)(customKey)-48;
}
if(i == 2&&customKey)
c = (int)(customKey)-48;
if(i == 3&&customKey){
d = (int)(customKey)-48;
}
if(customKey == '*')
a=b=c=d=q=i=0;
else if(customKey == '#')
{
q = a*1000 b*100 c*10 d;
EEPROM.write(0,q);
delay(100);
pass = EEPROM.read(0);
Serial.println(pass);
break;
}
if(customKey == '0'||customKey == '1'||customKey == '2'||customKey == '3'||customKey == '4'||customKey == '5'||customKey == '6'||customKey == '7'||customKey == '8'||customKey == '9')
{
i ;
if(i == 4)
{i = 0;}
}
}
}
if(customKey == 'B')
{
int a,b,c,d,q,i=0;
char customKey = ' ';
while(1)
{
char customKey = customKeypad.getKey();
if (customKey){
Serial.println(customKey);
}
if(i == 0&&customKey&&customKey!='#')
a = (int)(customKey)-48;
if(i == 1&&customKey)
{
b = (int)(customKey)-48;
}
if(i == 2&&customKey)
c = (int)(customKey)-48;
if(i == 3&&customKey){
d = (int)(customKey)-48;
}
if(customKey == '0'||customKey == '1'||customKey == '2'||customKey == '3'||customKey == '4'||customKey == '5'||customKey == '6'||customKey == '7'||customKey == '8'||customKey == '9')
{
i ;
if(i == 4)
{i = 0;}
}
if(customKey == '*'){
a=b=c=d=q=i=0;
}
else if(customKey == '#')
{
Serial.println(a);
Serial.println(b);
Serial.println(c);
Serial.println(d);
q = a*1000 b*100 c*10 d;
if(q == pass)
{
Serial.println("sucess");
digitalWrite(13, HIGH);
break;
}
else
{
a=b=c=d=q=i=0;
}
}
}
}
}
