防护/解除防护家庭安全系统arduino键盘lcd

Question

所以当我试图解除系统的武装时，我遇到了一个问题。当我将代码上传到arduino时，它会要求我输入个人识别码，然后它会立即激活系统。但是，当我尝试停用系统时，它会取出引脚，清除屏幕并执行我设置的mainScreen函数。

代码如下：

#include "Keypad.h"
#include "LiquidCrystal.h"
#include "Password.h"
LiquidCrystal lcd(0,1,10,11,12,13);
char newPasswordString; //hold the new password
char newPassword[4]; //charater string of newPasswordString

//initialize password to 1234
//you can use password.set(newPassword) to overwrite it
Password password = Password("1234");

byte maxPasswordLength = 4; 
byte currentPasswordLength = 4;
// keypad type definition
const byte ROWS = 4; //four rows
const byte COLS = 4; //three columns
char keys[ROWS][COLS] = {
{'1','2','3','A'},
{'4','5','6','B'},
{'7','8','9','C'},
{'*','0','#','D'}
};
byte rowPins[ROWS] = {9,8,7,6}; //Rows 0 to 3
byte colPins[COLS]= {5,4,3,2}; //Columns 0 to 3
int count=0;     
Keypad keypad = Keypad( makeKeymap(keys), rowPins, colPins, ROWS, COLS );
void setup()
{    
  lcd.begin(16, 2);
  mainScreen();
}
void loop(){
   char key = keypad.getKey();
   if (key != NO_KEY){
      delay(60); 
      switch (key){
      case 'A': activate(); break; 
      case 'B': break; 
      case 'C': break; 
      case 'D': deactivate(); break; 
      case '#':  break;
      case '*': break;
      default: processNumberKey(key);
      }
   }
}
void processNumberKey(char key) {
   lcd.print(key);
   currentPasswordLength++;
   password.append(key);
   if(password.evaluate()){
    activate();
   }
}    
void activate() {
   if (password.evaluate()){
      lcd.clear();
      lcd.print("Activated.");
      delay(1000);
      mainScreen();
   } else {
      lcd.clear();
      lcd.print("Wrong Password!");
            mainScreen();    
   } 
}
void deactivate(){
    if (password.evaluate()){
      lcd.clear();
      lcd.print("Deactivated.");
      delay(1000);
   } else {
      lcd.clear();
      lcd.print("Wrong Password!");
      mainScreen();
   } 
}
void mainScreen(){
  lcd.clear();
  lcd.print("Enter Pin:");
  keypad.getKey();
  }

Answer 1

正如在Arduino keypad 4x4 to LCD activate/deactivate中所指出的，您必须保持当前状态，并且必须清除 password和currenPasswordLength。请参阅答案中的工作示例。

设置byte currenPasswordLength = 4不会有任何帮助。如果按下第一个键，它将增加到5，下一个键增加到6，依此类推。

在256次按键后，您将再次得到4！由于你没有清除之前检查过的密码，你会得到“错误密码”的结果(最终堆栈溢出)。