please help

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1

hello,and thank you for your help ,i'm working on a small project
i'm trying to controle an LCD 16×2 screen with a 4×4 keypad using PCF8574A,all i need it to do is " a security password program .after entering the password i want to be able to insert a temperature degree like a kitochen oven when u enter the temperature to cook something please help me

PCF8574.jpg
PCF8574.jpg1251×872 333 KB

2

We know what you want. Now we need to know what you have done. Can you write to the LCD? Can you read a character or characters from the keypad? Can you display characters from the keypad on the LCD?

What code have you tried?

3

i found a password program online and i tried to add the temperture code but it wont work

#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <Keypad.h>

#define Password_Length 4

int signalPin = 12;

char Data[Password_Length];
char Master[Password_Length] = "123";
byte data_count = 0, master_count = 0;
bool Pass_is_good = false;
char customKey;

const byte ROWS = 4;
const byte COLS = 4;

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};
byte colPins[COLS] = {5, 4, 3, 2};

Keypad customKeypad = Keypad(makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS);

LiquidCrystal_I2C lcd(0X38, 16, 2);

void setup(){
lcd.init();
lcd.backlight();
pinMode(signalPin, OUTPUT);
}

void loop(){
if (Pass_is_good == true)
{
lcd.setCursor(0,0);
lcd.print("d");
lcd.setCursor(1,0);
lcd.print("o");
lcd.setCursor(2,0);
lcd.print("n");
lcd.setCursor(3,0);
lcd.print("n");lcd.setCursor(4,0);
lcd.print("e");lcd.setCursor(5,0);
lcd.print("r");lcd.setCursor(6,0);
lcd.print(" ");lcd.setCursor(7,0);
lcd.print("t");lcd.setCursor(8,0);
lcd.print("e");lcd.setCursor(9,0);
lcd.print("m");lcd.setCursor(10,0);
lcd.print("p");lcd.setCursor(11,0);

customKey = customKeypad.getKey();
if (customKey){
Data[data_count] = customKey;
lcd.setCursor(data_count,1);
lcd.print(Data[data_count]);
data_count++;
}
if(data_count == Password_Length-1){
lcd.clear();

lcd.setCursor(0,0);
lcd.print("t");
lcd.setCursor(1,0);
lcd.print("e");
lcd.setCursor(2,0);
lcd.print("m");
lcd.setCursor(3,0);
lcd.print("p");lcd.setCursor(4,0);
lcd.print(":");

lcd.setCursor(0,1);
lcd.print(Data[0]);
lcd.setCursor(1,1);
lcd.print(Data[1]);
lcd.setCursor(2,1);
lcd.print(Data[2]);

delay (2000);

lcd.clear();
clearData();

}

}
else
{
lcd.setCursor(0,0);
lcd.print("E");
lcd.setCursor(1,0);
lcd.print("n");
lcd.setCursor(2,0);
lcd.print("t");
lcd.setCursor(3,0);
lcd.print("e");lcd.setCursor(4,0);
lcd.print("r");lcd.setCursor(5,0);
lcd.print(" ");lcd.setCursor(6,0);
lcd.print("P");lcd.setCursor(7,0);
lcd.print("a");lcd.setCursor(8,0);
lcd.print("s");lcd.setCursor(9,0);
lcd.print("s");lcd.setCursor(10,0);
lcd.print("w");lcd.setCursor(11,0);
lcd.print("o");lcd.setCursor(12,0);
lcd.print("r:");lcd.setCursor(13,0);
lcd.print("d:");
}

customKey = customKeypad.getKey();
if (customKey){
Data[data_count] = customKey;
lcd.setCursor(data_count,1);
lcd.print(Data[data_count]);
data_count++;
}

if(data_count == Password_Length-1){
lcd.clear();

if(!strcmp(Data, Master)){
lcd.print("Correct");
digitalWrite(signalPin, HIGH); lcd.setCursor(0,0);
// lcd.print("donner la température : ");
delay(2000);
digitalWrite(signalPin, LOW);
Pass_is_good = true;
}
else{
lcd.print("Incorrect");
delay(1000);

}

lcd.clear();
clearData();

}
}

void clearData(){
while(data_count !=0){
Data[data_count--] = 0;
// if(!strcmp(Data, Master)&&(data_count == Password_Length-1)){ lcd.print("donner la temperature");}
}
return;
// if(!strcmp(Data, Master)&&(data_count == Password_Length-1)){ lcd.print("donner la temperature");}
}

4

"It won't work" is an inadequate description of the problem(s).

Please read this post on how to as a programming question. Following those guidelines will save us a lot of time.