lcd screen circuit diagram free sample

We come across Liquid Crystal Display (LCD) displays everywhere around us. Computers, calculators, television sets, mobile phones, digital watches use some kind of display to display the time.

An LCD screen is an electronic display module that uses liquid crystal to produce a visible image. The 16×2 LCD display is a very basic module commonly used in DIYs and circuits. The 16×2 translates o a display 16 characters per line in 2 such lines. In this LCD each character is displayed in a 5×7 pixel matrix.

Contrast adjustment; the best way is to use a variable resistor such as a potentiometer. The output of the potentiometer is connected to this pin. Rotate the potentiometer knob forward and backwards to adjust the LCD contrast.

A 16X2 LCD has two registers, namely, command and data. The register select is used to switch from one register to other. RS=0 for command register, whereas RS=1 for data register.

Command Register: The command register stores the command instructions given to the LCD. A command is an instruction given to LCD to do a predefined task. Examples like:

Data Register: The data register stores the data to be displayed on the LCD. The data is the ASCII value of the character to be displayed on the LCD. When we send data to LCD it goes to the data register and is processed there. When RS=1, data register is selected.

Generating custom characters on LCD is not very hard. It requires the knowledge about custom generated random access memory (CG-RAM) of LCD and the LCD chip controller. Most LCDs contain Hitachi HD4478 controller.

CG-RAM address starts from 0x40 (Hexadecimal) or 64 in decimal. We can generate custom characters at these addresses. Once we generate our characters at these addresses, we can print them by just sending commands to the LCD. Character addresses and printing commands are below.

LCD modules form a very important in many Arduino based embedded system designs to improve the user interface of the system. Interfacing with Arduino gives the programmer more freedom to customise the code easily. Any cost effective Arduino board, a 16X2 character LCD display, jumper wires and a breadboard are sufficient enough to build the circuit. The interfacing of Arduino to LCD display below.

The combination of an LCD and Arduino yields several projects, the most simple one being LCD to display the LED brightness. All we need for this circuit is an LCD, Arduino, breadboard, a resistor, potentiometer, LED and some jumper cables. The circuit connections are below.

In this project, I will show you how to interface a 128X64 Graphical LCD with Arduino UNO. This particular LCD Module is based ST7920 LCD Controller. So, we will first see a little bit about the Graphical LCD Module and its LCD Controller ST7920.

In the previous Arduino project, I have interfaced a Nokia 5110 LCD Module with Arduino. It is also a graphical LCD which can display some basic bitmap images and graphics. But the issue with Nokia 5110 LCD Module is its resolution.

At 84 x 48 pixels, the Nokia 5110 LCD can be used for implementing a menu-based user interface. Due to its small size, the resulting menu will be limited to 3 or 4 items per page.

If we want a bigger display with more real estate to work with, then the obvious choice is to go for the bigger and better 128×64 Graphical LCD Module.

As a demonstration, after making all the hardware connections, I will display a bitmap image on the Graphical LCD Module. If you are interested in implementing a simple 16×2 Alpha-Numeric LCD with Arduino, then check out this tutorial.

At first glance, the 128×64 Graphical LCD Module seems like a bigger brother to the famous 16×2 LCD or 20×4 LCD Modules, with their similar construction and almost similar pin layout.

But there is a significant difference between those two. 16×2 or 20×4 LCDs are essentially character displays. They can only display alpha-numeric characters and some simple custom characters that are confined to a 5×8 matrix.

By using different combinations of pixels, we can basically display characters of various sizes. But the magic doesn’t end there. You can display images and graphics (small animations) as well. In a 128×64 LCD Module, there are 64 rows and 128 columns.

There are several versions of the Graphical LCD in the market. Even though the usage, application and implementations are almost identical, the main difference lies in the internal LCD Controller used to drive the dot matrix display.

Some of the commonly used LCD Controllers are KS0108, SSD1306, ST7920, SH1106, SSD1322, etc. The pin out of the final LCD Module might vary depending on the LCD Controller used. So, please verify the LCD Controller as well as the pin out before making a purchase.

The Graphical LCD Module I purchased consists of ST7920 Controller. It is manufactured by Sitronix and supports three types of bus interfaces i.e., 8-bit mode, 4-bit mode and Serial interface.

If you have used 16×2 LCD Display earlier, then you might be familiar with both 4-bit as well as 8-bit parallel interfaces. The serial interface is something new and we will explore this option in this project.

As I already mentioned, double-check with the manufacturer about the pinout of the Graphical LCD Module. The following table describes the pinout of the 128×64 LCD Module that I have.

Now that we have seen a little bit about the Graphical LCD and its controller ST7920, let us now proceed with interfacing the 128×64 Graphical LCD with Arduino. I will implement a simple circuit to demonstrate how easy it is to interface the LCD and Arduino using very few external components.

So, connect the RS, RW and E of the LCD to Digital IO pins 10, 11 and 13 of Arduino UNO. Also, in order to select the Serial Interface Mode, the PCB pin must be connected to GND.

The remaining connections are similar to a traditional 16×2 LCD. VCC and GND are connected to 5V and ground of the power supply. VO is connected to the wiper of a 10KΩ POT while the other two terminals of the POT are connected to 5V and GND respectively.

I have used the above “The Office” logo. Remember that the resolution of the 128×64 LCD is, well 128×64 pixels. So, the maximum image size should be 128×64. So, using Microsoft Paint, I have brought down the resolution of the above image to 128×64 pixels and also saved it as Monochrome Bitmap Image.

A simple project for interfacing the 128×64 Graphical LCD with Arduino is implemented here. Instead of displaying plain characters, I have displayed a bitmap image on the LCD to show its capability.

In this tutorial, I’ll explain how to set up an LCD on an Arduino and show you all the different ways you can program it. I’ll show you how to print text, scroll text, make custom characters, blink text, and position text. They’re great for any project that outputs data, and they can make your project a lot more interesting and interactive.

The display I’m using is a 16×2 LCD display that I bought for about $5. You may be wondering why it’s called a 16×2 LCD. The part 16×2 means that the LCD has 2 lines, and can display 16 characters per line. Therefore, a 16×2 LCD screen can display up to 32 characters at once. It is possible to display more than 32 characters with scrolling though.

The code in this article is written for LCD’s that use the standard Hitachi HD44780 driver. If your LCD has 16 pins, then it probably has the Hitachi HD44780 driver. These displays can be wired in either 4 bit mode or 8 bit mode. Wiring the LCD in 4 bit mode is usually preferred since it uses four less wires than 8 bit mode. In practice, there isn’t a noticeable difference in performance between the two modes. In this tutorial, I’ll connect the LCD in 4 bit mode.

BONUS: I made a quick start guide for this tutorial that you can download and go back to later if you can’t set this up right now. It covers all of the steps, diagrams, and code you need to get started.

Here’s a diagram of the pins on the LCD I’m using. The connections from each pin to the Arduino will be the same, but your pins might be arranged differently on the LCD. Be sure to check the datasheet or look for labels on your particular LCD:

Also, you might need to solder a 16 pin header to your LCD before connecting it to a breadboard. Follow the diagram below to wire the LCD to your Arduino:

The resistor in the diagram above sets the backlight brightness. A typical value is 220 Ohms, but other values will work too. Smaller resistors will make the backlight brighter.

Now we’re ready to get into the programming! I’ll go over more interesting things you can do in a moment, but for now lets just run a simple test program. This program will print “hello, world!” to the screen. Enter this code into the Arduino IDE and upload it to the board:

There are 19 different functions in the LiquidCrystal library available for us to use. These functions do things like change the position of the text, move text across the screen, or make the display turn on or off. What follows is a short description of each function, and how to use it in a program.

TheLiquidCrystal() function sets the pins the Arduino uses to connect to the LCD. You can use any of the Arduino’s digital pins to control the LCD. Just put the Arduino pin numbers inside the parentheses in this order:

This function sets the dimensions of the LCD. It needs to be placed before any other LiquidCrystal function in the void setup() section of the program. The number of rows and columns are specified as lcd.begin(columns, rows). For a 16×2 LCD, you would use lcd.begin(16, 2), and for a 20×4 LCD you would use lcd.begin(20, 4).

This function clears any text or data already displayed on the LCD. If you use lcd.clear() with lcd.print() and the delay() function in the void loop() section, you can make a simple blinking text program:

This function places the cursor in the upper left hand corner of the screen, and prints any subsequent text from that position. For example, this code replaces the first three letters of “hello world!” with X’s:

Similar, but more useful than lcd.home() is lcd.setCursor(). This function places the cursor (and any printed text) at any position on the screen. It can be used in the void setup() or void loop() section of your program.

The cursor position is defined with lcd.setCursor(column, row). The column and row coordinates start from zero (0-15 and 0-1 respectively). For example, using lcd.setCursor(2, 1) in the void setup() section of the “hello, world!” program above prints “hello, world!” to the lower line and shifts it to the right two spaces:

You can use this function to write different types of data to the LCD, for example the reading from a temperature sensor, or the coordinates from a GPS module. You can also use it to print custom characters that you create yourself (more on this below). Use lcd.write() in the void setup() or void loop() section of your program.

The function lcd.noCursor() turns the cursor off. lcd.cursor() and lcd.noCursor() can be used together in the void loop() section to make a blinking cursor similar to what you see in many text input fields:

Cursors can be placed anywhere on the screen with the lcd.setCursor() function. This code places a blinking cursor directly below the exclamation point in “hello, world!”:

This function creates a block style cursor that blinks on and off at approximately 500 milliseconds per cycle. Use it in the void loop() section. The function lcd.noBlink() disables the blinking block cursor.

This function turns on any text or cursors that have been printed to the LCD screen. The function lcd.noDisplay() turns off any text or cursors printed to the LCD, without clearing it from the LCD’s memory.

This function takes anything printed to the LCD and moves it to the left. It should be used in the void loop() section with a delay command following it. The function will move the text 40 spaces to the left before it loops back to the first character. This code moves the “hello, world!” text to the left, at a rate of one second per character:

Like the lcd.scrollDisplay() functions, the text can be up to 40 characters in length before repeating. At first glance, this function seems less useful than the lcd.scrollDisplay() functions, but it can be very useful for creating animations with custom characters.

lcd.noAutoscroll() turns the lcd.autoscroll() function off. Use this function before or after lcd.autoscroll() in the void loop() section to create sequences of scrolling text or animations.

This function sets the direction that text is printed to the screen. The default mode is from left to right using the command lcd.leftToRight(), but you may find some cases where it’s useful to output text in the reverse direction:

This code prints the “hello, world!” text as “!dlrow ,olleh”. Unless you specify the placement of the cursor with lcd.setCursor(), the text will print from the (0, 1) position and only the first character of the string will be visible.

This command allows you to create your own custom characters. Each character of a 16×2 LCD has a 5 pixel width and an 8 pixel height. Up to 8 different custom characters can be defined in a single program. To design your own characters, you’ll need to make a binary matrix of your custom character from an LCD character generator or map it yourself. This code creates a degree symbol (°):

In this Arduino tutorial we will learn how to connect and use an LCD (Liquid Crystal Display)with Arduino. LCD displays like these are very popular and broadly used in many electronics projects because they are great for displaying simple information, like sensors data, while being very affordable.

You can watch the following video or read the written tutorial below. It includes everything you need to know about using an LCD character display with Arduino, such as, LCD pinout, wiring diagram and several example codes.

An LCD character display is a unique type of display that can only output individual ASCII characters with fixed size. Using these individual characters then we can form a text.

The number of the rectangular areas define the size of the LCD. The most popular LCD is the 16×2 LCD, which has two rows with 16 rectangular areas or characters. Of course, there are other sizes like 16×1, 16×4, 20×4 and so on, but they all work on the same principle. Also, these LCDs can have different background and text color.

Next, The RSpin or register select pin is used for selecting whether we will send commands or data to the LCD. For example if the RS pin is set on low state or zero volts, then we are sending commands to the LCD like: set the cursor to a specific location, clear the display, turn off the display and so on. And when RS pin is set on High state or 5 volts we are sending data or characters to the LCD.

Next comes the R/W pin which selects the mode whether we will read or write to the LCD. Here the write mode is obvious and it is used for writing or sending commands and data to the LCD. The read mode is used by the LCD itself when executing the program which we don’t have a need to discuss about it in this tutorial.

After all we don’t have to worry much about how the LCD works, as the Liquid Crystal Library takes care for almost everything. From the Arduino’s official website you can find and see the functions of the library which enable easy use of the LCD. We can use the Library in 4 or 8 bit mode. In this tutorial we will use it in 4 bit mode, or we will just use 4 of the 8 data pins.

We will use just 6 digital input pins from the Arduino Board. The LCD’s registers from D4 to D7 will be connected to Arduino’s digital pins from 4 to 7. The Enable pin will be connected to pin number 2 and the RS pin will be connected to pin number 1. The R/W pin will be connected to Ground and theVo pin will be connected to the potentiometer middle pin.

We can adjust the contrast of the LCD by adjusting the voltage input at the Vo pin. We are using a potentiometer because in that way we can easily fine tune the contrast, by adjusting input voltage from 0 to 5V.

Yes, in case we don’t have a potentiometer, we can still adjust the LCD contrast by using a voltage divider made out of two resistors. Using the voltage divider we need to set the voltage value between 0 and 5V in order to get a good contrast on the display. I found that voltage of around 1V worked worked great for my LCD. I used 1K and 220 ohm resistor to get a good contrast.

There’s also another way of adjusting the LCD contrast, and that’s by supplying a PWM signal from the Arduino to the Vo pin of the LCD. We can connect the Vo pin to any Arduino PWM capable pin, and in the setup section, we can use the following line of code:

It will generate PWM signal at pin D11, with value of 100 out of 255, which translated into voltage from 0 to 5V, it will be around 2V input at the Vo LCD pin.

First thing we need to do is it insert the Liquid Crystal Library. We can do that like this: Sketch > Include Library > Liquid Crystal. Then we have to create an LC object. The parameters of this object should be the numbers of the Digital Input pins of the Arduino Board respectively to the LCD’s pins as follow: (RS, Enable, D4, D5, D6, D7). In the setup we have to initialize the interface to the LCD and specify the dimensions of the display using the begin()function.

The cursor() function is used for displaying underscore cursor and the noCursor() function for turning off. Using the clear() function we can clear the LCD screen.

So, we have covered pretty much everything we need to know about using an LCD with Arduino. These LCD Character displays are really handy for displaying information for many electronics project. In the examples above I used 16×2 LCD, but the same working principle applies for any other size of these character displays.

Printing “Hello, world!” is usually the first thing that programming tutorials will have you do in a new language. This guide starts by blinking an LED, but now we’re going to print out real text using a Liquid Crystal Display (LCD).

Character LCDs are designed to show a grid of letters, numbers and a few special characters. This makes them great for printing data and showing values. When current is applied to this special kind of crystal, it turns opaque. This is used in a lot of calculators, watches and simple displays. Adding an LCD to your project will make it super portable and allow you to integrate up to 32 characters (16 x 2) of information.

Pin 3 on the LCD controls the contrast and brightness of the LCD. Using a simple voltage divider with a potentiometer, the contrast can be adjusted. As you rotate the knob on the potentiometer, you should notice that the screen will get brighter or darker and that the characters become more visible or less visible. The contrast of LCDs is highly dependent on factors such as temperature and the voltage used to power it. Thus, external contrast knobs are needed for displays that cannot automatically account for temperature and voltage changes.

If you look closely at the characters on the LCD, you will notice that they are actually made up of lots of little squares. These little squares are called pixels. The size of displays is often represented in pixels. Pixels make up character space, which is the number of pixels in which a character can exist.

Pay special attention to the component’s markings indicating how to place it on the breadboard. Polarized components can only be connected to a circuit in one direction.

The LCD has 16 pins, and it is polarized. The pins are numbered from left to right, 1 through 16. The LCD utilizes an extremely common parallel interface LCD driver chip from Hitachi called the HD44780. Thankfully, the Arduino community has developed a library to handle a great deal of the software-to-hardware interface. Below is a list of each of the pins on the LCD.

“Begin” the LCD. This sets the dimensions of the LCD that you are working with (16 x 2). It needs to be called before any other commands from the LCD library are used.

Move the cursor to the first space of the lower line lcd.setCursor(0,1);, then print the number of seconds that have passed since the RedBoard was last reset.

LiquidCrystal LCD_name(RS_pin, enable_pin, d4, d5, d6, d7);As with servos, you need to create an LCD object and give it a name (you can make more than one). The numbers in the brackets are pins on the RedBoard that connect to specific pins on the LCD.

lcd.setCursor(0,0);Move the cursor to a point on the 16x2 grid of characters. Text that you write to the LCD will start from the cursor. This line is starting back at position (0,0).

Count button pressesBy adding a button to the circuit, you can count the number of times the button was pressed or have the button change what the LCD is displaying. There could be many pages of information.

The screen is blank or flickeringAdjust the contrast by twisting the potentiometer. If it’s incorrectly adjusted, you won’t be able to read the text. Also, check the potentiometer, and make sure it"s connected correctly.

Rectangles in first rowIf you see 16 rectangles (like “█”) on the first row, it may be due to the jumper wires being loose on the breadboard. This is normal and can happen with other LCDs wired in parallel with a microcontroller. Make sure that the wires are fully inserted into the breadboard, then try pressing the reset button and adjusting the contrast using the potentiometer.

Still not working?Jumper wires unfortunately can go "bad" from getting bent too much. The copper wire inside can break, leaving an open connection in your circuit. If you are certain that your circuit is wired correctly and that your code is error-free and uploaded but you are still encountering issues, try replacing one or more of the jumper wires for the component that is not working.

I recently received some free LCD samples from my friends at FocusLCDs.com. One of which is a 16x4 LCD; P/N: C164AXBSYLY6WT. It uses a ST7066U controller (see datasheet here) instead of the HD44780 commonly found in LCD shields. I am not so sure if it will work with an Arduino and its libraries, so I wanted to try it out.

LCD Displays are a fast and inexpensive way to display simple information. This tutorial will demonstrate how to connect a 16x2 LCD display using I2C to an ESP8266 NodeMCU dev kit.

The LCD display I"m going to use is fairly common and can be picked up for a couple of bucks from Amazon. It uses I2C to communicate with the NodeMCU. I2C is nice because it only required two wires for communication.

Connect the VCC pin on the LCD display to the VIN pin on the NodeMCU. The VIN pin on the NodeMCU is tied directly to the 5V pin on the incoming USB port. If you plan on powering the NodeMCU with something other than USB, you"ll have to find another way to provide 5V to the display.

The LCD display works by first moving the cursor to where you want to start and then printing some characters. In my example, I wanted HELLO and WORLD to be centered on each line. For "HELLO", the cursor needed to be 5 characters from the right and zero characters down, so I moved it (5, 0). For "WORLD", I needed it to be 5 characters to the right and one character down, so I moved it (5, 1).