LCD doesn't work in a simulated enviroment

Question

I'm using Tinkercad, and since it's my first time programming an LCD I just copied the procedure to connect the pins and make it work.

The thing is that it just lights up without displaying anything, I tried both wiring and unwiring the R/W pin but that doesn't work either, nothing will be displayed.

What did I miss? The other functions of the code works normally.

Image of the circuit:

Image of the circuit

This is the code:

#include <LiquidCrystal.h>

const int pin = 0; // analog pin
float celsius = 0, farhenheit =0; // temperature variables
float millivolts; //Millivolts from the sensor
int sensor;

const int G_LED = 13;
const int Y_LED = 12;
LiquidCrystal lcd(10, 9, 5, 4, 3, 2); // Building the LCD


void setup() {
  lcd.begin(16,2);              
  lcd.clear();                  
  lcd.setCursor(0,0);           
  lcd.print("C=");           // "C=", "F=" and "mV" should be printed
  lcd.setCursor(0, 1);       // on the LCD in a column  
  lcd.print("F=");           
  lcd.setCursor(0, 2);            
  lcd.print("mV=");
  
  pinMode(G_LED, OUTPUT);
  pinMode(Y_LED, OUTPUT);

  Serial.begin(9600); 
}

void loop() {
  sensor = analogRead(pin);                    // Reading the value from the LM35 sensor using the A0 ingress
  millivolts = (sensor / 1023.0) * 5000;       // Converting the value in a number that indicates the millivolts
  celsius = ((sensor * 0.00488) - 0.5) / 0.01; // Celsius value (10 mV for each degree, 0°=500mV)
  farhenheit = celsius * 1.8 + 32;             // Fahrenheit value
 
  lcd.setCursor(4, 2);                         // Set the cursor at the right of "mV="
  lcd.print(millivolts);                       // Print the mV value
  lcd.setCursor(4, 0);                         // Same here for °C and °F
  lcd.print(celsius);
  lcd.setCursor(4, 1);

  Serial.print(farhenheit);

  if (millivolts < 700) {    // Green LED is on when the temperature is under or equal to 20° 
  // if (celsius < 20) {     // Alternative
    analogWrite(G_LED, 255);
    analogWrite(Y_LED, 0); }
  else {
    analogWrite(G_LED, 0);
    analogWrite(Y_LED, 255); // Yellow LED is on when the temperature is above of 20°C
  }  
  delay(1000);
}

Have you tried this pin-out in real life? also please link the Tinker-CAD sketch. — James Barnett, Dec 24 '20 at 11:05
@JamesBarnett no I haven't tried yet, I don't even have the materials, here's the tinkercad link: https://www.tinkercad.com/things/crc5uG2Br5x — Wandering, Dec 26 '20 at 16:47
I think the issue is due to the fact that you have used a hard to use pin-out, try a more conventional method. (P.S: You have not setup any sensors in Tinkercad). I will answer the question when I fix the problem or find an alternative). — James Barnett, Dec 26 '20 at 21:37

score 0 · Accepted Answer · answered Dec 26 '20 at 22:16

Fix - I could not find the error, but I suspect it was due to the strange layout of the connections. You also tried to set the cursor to line 3, but the LCD you were using did not have 3 lines, it was a 16x2 LCD.

What I Did - So what I did was I re-did the entire project, I linked up a new LCD, this time with a digital contrast so that it could be dynamically changed. I also made sure to include the sensor you used in your last project. Over-all the project is an Arduino controlling an LCD and outputting the temperature in Fahrenheit and millivolts.

Here is the project link (Tinkercad).

Code:

#include <LiquidCrystal.h> 
// Adds the liquid crystal lib

int contrast = 40; // Set the contrast of the LCD
LiquidCrystal lcd (12, 11, 5, 4, 3, 2); // Instantiate the LCD

float fahrenheit;
float millivolts;

void setup ()
{
  analogWrite(6, contrast); // Wrjte the contrast to the LCD
  lcd.begin(16, 2); // Init the LCD
}

void loop ()
{
  int sensor = analogRead(0);
  millivolts = (sensor/1023.0)*5000;
  fahrenheit = (((sensor*0.00488)-0.5)/0.01)*1.8+32;
  
  lcd.setCursor(0, 0); 
  lcd.print("Temp(F):");
  lcd.setCursor(11, 0);
  lcd.print(fahrenheit);
  
  lcd.setCursor(0, 1);
  lcd.print("Volts(mV):");
  lcd.setCursor(12, 1);
  lcd.print(millivolts);
}

Diagram

LCD doesn't work in a simulated enviroment

1 Answers1