Strange problem, after giving lcd.clear();

Using Arduino Programming Questions
1

My code is working fine, that's for sure.
Everything is fine, the text displays on the lcd, but when i give lcd.clear();
and then tell it to write something, there is no output.
Please help me fix this problem
Thanks
Arduinodeveloper99.

2

You do need to post your code in order for someone to be able to help.

3

there is nothing wrong with the code
#include <SPI.h>
#include <MFRC522.h>
#include <LiquidCrystal.h>

#define SS_PIN 10
#define RST_PIN 9
MFRC522 mfrc522(SS_PIN, RST_PIN); // Create MFRC522 instance.

#define beep_pin 8

LiquidCrystal lcd(2, 3, 4, 5, 6, 7);

void setup()
{
Serial.begin(9600); // Initiate a serial communication

pinMode(beep_pin,OUTPUT);
digitalWrite(beep_pin,LOW);

lcd.begin(16, 2);
lcd.setCursor(3, 1);
lcd.print("Welcome!!");
lcd.setCursor(0, 0);
lcd.print("Circuit is Ready");
delay(1500);
lcd.clear();

SPI.begin(); // Initiate SPI bus
mfrc522.PCD_Init(); // Initiate MFRC522
Serial.println("Put your card to the reader...");
Serial.println();

}
void loop()
{
digitalWrite(beep_pin, LOW);
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("Put your card to");
lcd.setCursor(0, 1);
lcd.print("the reader......");
delay(300);

// Look for new cards
if ( ! mfrc522.PICC_IsNewCardPresent())
{
return;
}
// Select one of the cards
if ( ! mfrc522.PICC_ReadCardSerial())
{
return;
}
//Show UID on serial monitor
Serial.print("UID tag :");
String content= "";
byte letter;
for (byte i = 0; i < mfrc522.uid.size; i++)
{
Serial.print(mfrc522.uid.uidByte[i] < 0x10 ? " 0" : " ");
Serial.print(mfrc522.uid.uidByte[i], HEX);
content.concat(String(mfrc522.uid.uidByte[i] < 0x10 ? " 0" : " "));
content.concat(String(mfrc522.uid.uidByte[i], HEX));
}
Serial.println();
Serial.print("Message : ");
content.toUpperCase();

if (content.substring(1) == "XX XX XX XX") //change here the UID of the card/cards that you want to give access
{
digitalWrite(beep_pin,HIGH);
delay(200);
digitalWrite(beep_pin,LOW);
delay(100);
lcd.setCursor(0, 0);
lcd.print("ID : ");
lcd.print(content.substring(1));
lcd.setCursor(0, 1);
lcd.print("Authorized access");
Serial.println("Authorized access");
delay(1200);
}

else {
digitalWrite(beep_pin,HIGH);
lcd.setCursor(0, 0);
lcd.print("ID : ");
lcd.print(content.substring(1));
lcd.setCursor(0, 1);
lcd.print("Access denied");
Serial.println(" Access denied");
delay(1500);
}
}

4

Ok, then, if there’s nothing wrong with the code, show us the hardware - photos and schematic… but I can see a possible problem in the code that I wouldn't use.

5

Yay i fixed the problem

6

the problem was with the name of the library
it was liquid crystal when it was supposed to be liquid crystal _I2C

7

When posting code in future please follow the advice given in the link below when posting code , use code tags and post the code here to make it easier to read and copy for examination

8

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