LCD category

How to Set Up and Program an LCD Display on an Arduino

circuitbasics.com has a tutorial on how to setup an LCD with Arduino.

In this tutorial, I’ll explain how to set up an LCD display on an Arduino, and show you all the functions available to program it (with examples). The display I’m using here is a 16×2 LCD display that I bought for under $10 on Amazon. LCDs are really useful in projects that output data, and they can make your project a lot more interesting and interactive.

How to Set Up and Program an LCD Display on an Arduino – [Link]

4Duino – An Introduction and a Weather API Demo


We covered 4Duino in one of our previous blog posts. 4Duino is a 2.4” Arduino based programmable display module. In our article today, we are presenting a hands-on experience with this product by building a simple project. Many thanks to 4D Systems for sending us a sample and giving us a chance to try this new product.

4Duino – An Introduction and a Weather API Demo – [Link]

0.91 inch OLED display targets wearables

Winstar’s WEO012832F is a small OLED display featuring 128×32 pixels in a 0.91 inch diagonal screen, suitable for wearable devices. by Julien Happich @ edn-europe.com:

The WEO012832F module comes with a built-in SSD1306BZ controller IC, it supports an I 2C interface and a 14-pin FPC pinout.  Standard emitting colours for the WEO012832F are available in white, sky blue and yellow. The WEO012832F features a COG structure OLED display, the built-in voltage generation only requires a single 3V power supply. This lightweight 30.0×11.5×1.45mm OLED module can operate at temperatures from -40℃ to +80℃.

0.91 inch OLED display targets wearables – [Link]

Alarm System Powered By Arduino

Dejan Nedelkovski had built an Arduino security and alarm system project that uses an ultrasonic sensor for detecting objects and a buzzer for notification.

Components needed to build this simple system are: Arduino board, LCD display, 4×4 keypad, ultrasonic sensor and buzzer. The circuit can be connected as shown in the schematics below.

In order to build the project, you have to connect the buzzer with a PWM pin and the keypad pins where 4 of the 8 pins are for rows and the rest are for columns.

“The 4×4 keypad has 8 pins, 4 of them are for the rows and 4 of them for the columns of the keypad. Each button is actually a push button switch which makes a short between one row and column when pressed. So, for example, if we set the row 1 line low, and all column lines high, when we will press, for example, the button 3, due to the short between the two lines, the column 3 line will drop to low so in such a case we can register that the button 3 has been pressed.”

For connecting the LCD display and ultrasonic sensor you can check this detailed video tutorial by Dejan Nedelkovski and to see the project in action:

We want to activate the alarm by setting the A button to activate it. B button is used to change the password, and you need to enter the preset password “1234” to be able to change it.
After activating the alarm by pressing A, a 200 milliseconds sound will be produced from the buzzer showing that the alarm is now active. A message on the LCD display will appear to saying “Alarm will be activated in” and a countdown will be running afterwards until the alarm is completely active. At the end of the countdown a ” Alarm Activated” is on the display and the sensor will start working. Comparing with the initial distance at the start, the sensor will measure the distance is smaller than the initial distance, corrected by a value of 10 cms. The buzzer will  produce a sound if an object is observed as per the condition.

Here’s the complete source code of the Arduino alarm system:

/*
* Arduino Security and Alarm System
*
* by Dejan Nedelkovski,
* www.HowToMechatronics.com
*
*/
#include <LiquidCrystal.h> // includes the LiquidCrystal Library 
#include <Keypad.h>
#define buzzer 8
#define trigPin 9
#define echoPin 10
long duration;
int distance, initialDistance, currentDistance, i;
int screenOffMsg =0;
String password="1234";
String tempPassword;
boolean activated = false; // State of the alarm
boolean isActivated;
boolean activateAlarm = false;
boolean alarmActivated = false;
boolean enteredPassword; // State of the entered password to stop the alarm
boolean passChangeMode = false;
boolean passChanged = false;
const byte ROWS = 4; //four rows
const byte COLS = 4; //four columns
char keypressed;
//define the cymbols on the buttons of the keypads
char keyMap[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'}
};
byte rowPins[ROWS] = {14, 15, 16, 17}; //Row pinouts of the keypad
byte colPins[COLS] = {18, 19, 20, 21}; //Column pinouts of the keypad
Keypad myKeypad = Keypad( makeKeymap(keyMap), rowPins, colPins, ROWS, COLS); 
LiquidCrystal lcd(1, 2, 4, 5, 6, 7); // Creates an LC object. Parameters: (rs, enable, d4, d5, d6, d7) 
void setup() { 
  lcd.begin(16,2); 
  pinMode(buzzer, OUTPUT); // Set buzzer as an output
  pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output
  pinMode(echoPin, INPUT); // Sets the echoPin as an Input
}
void loop() {
  if (activateAlarm) {
    lcd.clear();
    lcd.setCursor(0,0);
    lcd.print("Alarm will be");
    lcd.setCursor(0,1);
    lcd.print("activated in");
   
    int countdown = 9; // 9 seconds count down before activating the alarm
    while (countdown != 0) {
      lcd.setCursor(13,1);
      lcd.print(countdown);
      countdown--;
      tone(buzzer, 700, 100);
      delay(1000);
    }
    lcd.clear();
    lcd.setCursor(0,0);
    lcd.print("Alarm Activated!");
    initialDistance = getDistance();
    activateAlarm = false;
    alarmActivated = true;
  }
  if (alarmActivated == true){
      currentDistance = getDistance() + 10;
      if ( currentDistance < initialDistance) {
        tone(buzzer, 1000); // Send 1KHz sound signal 
        lcd.clear();
        enterPassword();
      }
    }
  if (!alarmActivated) {
    if (screenOffMsg == 0 ){
      lcd.clear();
      lcd.setCursor(0,0);
      lcd.print("A - Activate");
      lcd.setCursor(0,1);
      lcd.print("B - Change Pass");
      screenOffMsg = 1;
    }
    keypressed = myKeypad.getKey();
     if (keypressed =='A'){        //If A is pressed, activate the alarm
      tone(buzzer, 1000, 200);
      activateAlarm = true;            
    }
    else if (keypressed =='B') {
      lcd.clear();
      int i=1;
      tone(buzzer, 2000, 100);
      tempPassword = "";
      lcd.setCursor(0,0);
      lcd.print("Current Password");
      lcd.setCursor(0,1);
      lcd.print(">");
      passChangeMode = true;
      passChanged = true;   
      while(passChanged) {      
      keypressed = myKeypad.getKey();
      if (keypressed != NO_KEY){
        if (keypressed == '0' || keypressed == '1' || keypressed == '2' || keypressed == '3' ||
            keypressed == '4' || keypressed == '5' || keypressed == '6' || keypressed == '7' ||
            keypressed == '8' || keypressed == '9' ) {
         tempPassword += keypressed;
         lcd.setCursor(i,1);
         lcd.print("*");
         i++;
         tone(buzzer, 2000, 100);
        }
      }
      if (i > 5 || keypressed == '#') {
        tempPassword = "";
        i=1;
        lcd.clear();
        lcd.setCursor(0,0);
        lcd.print("Current Password");
        lcd.setCursor(0,1);
        lcd.print(">"); 
      }
      if ( keypressed == '*') {
        i=1;
        tone(buzzer, 2000, 100);
        if (password == tempPassword) {
          tempPassword="";
          lcd.clear();
          lcd.setCursor(0,0);
          lcd.print("Set New Password");
          lcd.setCursor(0,1);
          lcd.print(">");
          while(passChangeMode) {
            keypressed = myKeypad.getKey();
            if (keypressed != NO_KEY){
              if (keypressed == '0' || keypressed == '1' || keypressed == '2' || keypressed == '3' ||
                  keypressed == '4' || keypressed == '5' || keypressed == '6' || keypressed == '7' ||
                  keypressed == '8' || keypressed == '9' ) {
                tempPassword += keypressed;
                lcd.setCursor(i,1);
                lcd.print("*");
                i++;
                tone(buzzer, 2000, 100);
              }
            }
            if (i > 5 || keypressed == '#') {
              tempPassword = "";
              i=1;
              tone(buzzer, 2000, 100);
              lcd.clear();
              lcd.setCursor(0,0);
              lcd.print("Set New Password");
              lcd.setCursor(0,1);
              lcd.print(">");
            }
            if ( keypressed == '*') {
              i=1;
              tone(buzzer, 2000, 100);
              password = tempPassword;
              passChangeMode = false;
              passChanged = false;
              screenOffMsg = 0;
            }            
          }
        }
      }
    }
   }
 }
}
void enterPassword() {
  int k=5;
  tempPassword = "";
  activated = true;
  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print(" *** ALARM *** ");
  lcd.setCursor(0,1);
  lcd.print("Pass>");
      while(activated) {
      keypressed = myKeypad.getKey();
      if (keypressed != NO_KEY){
        if (keypressed == '0' || keypressed == '1' || keypressed == '2' || keypressed == '3' ||
            keypressed == '4' || keypressed == '5' || keypressed == '6' || keypressed == '7' ||
            keypressed == '8' || keypressed == '9' ) {
          tempPassword += keypressed;
          lcd.setCursor(k,1);
          lcd.print("*");
          k++;
        }
      }
      if (k > 9 || keypressed == '#') {
        tempPassword = "";
        k=5;
        lcd.clear();
        lcd.setCursor(0,0);
        lcd.print(" *** ALARM *** ");
        lcd.setCursor(0,1);
        lcd.print("Pass>");
      }
      if ( keypressed == '*') {
        if ( tempPassword == password ) {
          activated = false;
          alarmActivated = false;
          noTone(buzzer);
          screenOffMsg = 0; 
        }
        else if (tempPassword != password) {
          lcd.setCursor(0,1);
          lcd.print("Wrong! Try Again");
          delay(2000);
          lcd.clear();
          lcd.setCursor(0,0);
          lcd.print(" *** ALARM *** ");
          lcd.setCursor(0,1);
          lcd.print("Pass>");
        }
      }    
    }
}
// Custom function for the Ultrasonic sensor
long getDistance(){
  //int i=10;
  
  //while( i<=10 ) {
  // Clears the trigPin
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  // Sets the trigPin on HIGH state for 10 micro seconds
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  // Reads the echoPin, returns the sound wave travel time in microseconds
  duration = pulseIn(echoPin, HIGH);
  // Calculating the distance
  distance = duration*0.034/2;
  //sumDistance += distance;
  //}
  //int averageDistance= sumDistance/10;
  return distance;
}

Check the project post to know more information and to find detailed tutorial. You can also check other posts by Dejan using this link.

RELATED POSTS

Arduino Tutorial: Menu on a Nokia 5110 LCD Display Tutorial

In this easy Arduino Tutorial educ8s.tv is going to show us how to create a Menu on a Nokia 5110 LCD display.

This is the project we are going to build. In the display a simple menu appears, and with the help of three buttons I can navigate up, or down and select a menu item. Let’s select the first option. As you can see a new a UI screen is displayed and by pressing the up and down buttons we can change the contrast of the display. If we press the middle button again, we go back to the main UI screen. If we now select the second menu item and press the middle button we can turn the backlight of the display on or off. Lastly if we navigate to the last menu item we can reset the settings for the display to the default values. Of course this is just a demonstration project, you can modify it to build your own more complex menus if you wish. Let’s now see how to build this project.

Arduino Tutorial: Menu on a Nokia 5110 LCD Display Tutorial [Link]

How to Set Up and Program an LCD Display on an Arduino

circuitbasics.com writes:

In this tutorial, I’ll explain how to set up an LCD display on an Arduino, and show you all the functions available to program it (with examples). The display I’m using here is a 16×2 LCD display that I bought for under $10 on Amazon. LCDs are really useful in projects that output data, and they can make your project a lot more interesting and interactive.

How to Set Up and Program an LCD Display on an Arduino – [Link]

1K LCD Tinyfont

A tiny pixel font rendered to an LCD display, in under 1K program space. by Zach:

For the Hackaday 1k challenge, I’m attempting to pack a small pixel-based font and rendering to LCD in under 1K.

The project has already been developed in C, but the file size was much larger. This is rewrite in assembly.

Developed on an Atmega328p using a display from a Nokia 5110 on a Sparkfun dev board.

1K LCD Tinyfont – [Link]

Bitmap graphics on an Arduino Touch Screen and other top Arduino Displays

In this video tutorial educ8s.tv shows us how to load bitmap graphics in our Arduino Touch Screen projects using Adafruit’s GFX library.

The procedure that I am going to describe works with all the color displays that are supported by Adafruit’s GFX library and by the displays that use the TFTLCD library from Adafruit with a small modification. So from the displays I own I can use the color OLED display, the 1.8” ST7735 color TFT display, the 2.8” Color Touch Screen that I reviewed a few weeks ago and the 3.5” Color TFT display. You can find links for all the displays below.

Bitmap graphics on an Arduino Touch Screen and other top Arduino Displays [Link]

Choose The Best Display For Your Arduino Project

Have you ever been unsure which display you should be using in your next project? This tutorial from educ8s.tv will come in handy for choosing the best display for your each and every Arduino project!

There are lots of choices, so let’s talk about each one of them. Basically, you have three types of displays: LCD displays, OLED displays, and E-paper displays.

LCD displays: LCD (liquid crystal display) is the technology used for displays in notebook and other smaller computers. Like light-emitting diode (LED) and gas-plasma technologies, LCDs allow displays to be much thinner than cathode ray tube (CRT) technology. LCD display is a flat-panel display or other electronic visual display that uses the light-modulating properties of liquid crystals.

One of the famous LCD displays is Nokia 5110 LCD display, a basic graphic LCD screen for lots of applications. It was originally intended for as a cell phone screen.

6851997-danbo-wallpaper

Its controller is a low power CMOS LCD controller which makes it a good choice for low-consumption projects. It uses only 0.4mA when it is on and less than 0.06mA when in sleep mode. You have to use this library and you don’t need more than 8 wires to start using this display. This tutorial video will show you with details how to use Nokia 5110 LCD with Arduino:

A second choice is the OLED displays. OLED is an organic light emitting diode in which the emissive electroluminescent layer is a film of organic compound that emits light in response to an electric current. An OLED display works without a backlight; it can display deep black levels and can be thinner and lighter than a liquid crystal display. Thus, it is provides better contrast than the LCD choice but it becomes a bit more expensive.

color_oled

One of the newest OLED displays is the color SSD1331 display that can display 65.000 colors. Just download its library from Adafruit and start using it. A video explaining how to use it is available here.

The last type is E-paper displays, that mimic the appearance of ordinary ink on paper.

lg-paper

Unlike LCD or OLED displays, these displays reflect light instead of emitting it. Such displays are great for low power projects since they have the ability to keep the text or the image you had set before for a really long time and without electricity. One of these displays disadvantages that they are absolutely costly compared with other choices, some displays can reach $60!

Color TFT Display ST7735, White OLED Display SSD1306 and 3.5″ Color TFT Display are all mentioned in the tutorial. You should check it out for more details, information, and some hardware offers.

The tutorial concludes with this interactive table based on different criteria, this is ordered progressively by price. You can compare between displays here.

display