low power lcd display arduino in stock

This graphic LCD module acts as a shield for Arduino Uno-style microcontrollers. The pins on the carrier board match up to the Arduino Uno"s ports, so the module simply presses on and is fully and correctly connected. Plus, this carrier board is able to be connected to either a 3.3v logic level or a 5v logic level device. (Read our blog post if you have questions about logic level.)

This module is also available with a white-on-blue graphic display, or as a fully built kit with an included Seeeduino (Arduino Uno clone) loaded with code to demonstrate the graphic display.

I"m drooling over Sharp Memory LCD, but they are pricey. I mean $40 is not terrible for one, but I need to get a bunch for battery powered LCD boards I"m working on

From my breadboard tests ATmega328p board w/ Nokia 5110 is using 140-170uA (depending on number of characters on display) when chip is sleeping which is not bad at all, but I want to explore all alternatives...

Alas I don"t know of a display that matches your requirements (price/power) and apart from an e-ink or memory LCD that updates vary rarely I don"t think you will ever get one to run for a year on 2x AAA batteries.

The reflective version (without backlight) of the DOGS102 might meet your requirements. According to the datasheet, the current will be 250uA for LCD and LCD-Controller (if I interpret the datasheet correctly).

The reflective version (without backlight) of the DOGS102 might meet your requirements. According to the datasheet, the current will be 250uA for LCD and LCD-Controller (if I interpret the datasheet correctly).

Alas I don"t know of a display that matches your requirements (price/power) and apart from an e-ink or memory LCD that updates vary rarely I don"t think you will ever get one to run for a year on 2x AAA batteries.

Yeah you could be right. Besides display I forgot that I need to keep radio module awake, that eats a lot of power. But how they heck do they do this with commercial temperature/humidity devices? I have one that"s been running for 2 years on single AA battery

Yeah you could be right. Besides display I forgot that I need to keep radio module awake, that eats a lot of power. But how they heck do they do this with commercial temperature/humidity devices? I have one that"s been running for 2 years on single AA battery

My commercial module only last about 6 months on 2x AAA. It would probably last longer without the LCD to display temperature/humidity and flash an LED every time it transmits (every 30 seconds). Your doing very well with yours, must have one of them plutonium batteries.

Note that these do not use the highly multiplexed display system with the bias ladder of the graphical or 1602/ 2004 devices, they are generally one pin per segment so the electronics is far more efficient.

Darn. I"ve been searching and it seems everyone in Arduinoland uses OLEDs and TFTs. I want a 1" display that I can run off of a coin battery for a year. I know they exist, I own a bunch of them. But the best thing I"ve found draws 125uA.

That"s a 2.2" display. I"m looking for a 1" display, like many of the little OLEDs you can buy on eBay for $5 or less. But with 1/500th the power consumption. My $10 wristwatch has a display like that.

It appears that you simply haven"t weighed up the real issues. If you finally get a display with 1/500th the consumption of what ever, all you get is that but, if that is what you need, the real problem isn"t the display and never was. It"s the Arduino that drives it.

I"m not planning on using an Arduino. Why would you assume that? If the display drew 20uA instead of 10mA it would still be the major consumer of current.

Fair enough. What"s an Arduino? AVR (and non-AVR) chips are also discussed in this forum. But even an official Arduino board like the Pro Mini, with the regulator isolated, is capable of drawing a very low average current.

Adding a display to your Arduino can serve many purposes. Since a common use for microcontrollers is reading data from sensors, a display allows you to see this data in real-time without needing to use the serial monitor within the Arduino IDE. It also allows you to give your projects a personal touch with text, images, or even interactivity through a touch screen.

Transparent Organic Light Emitting Diode (TOLED) is a type of LED that, as you can guess, has a transparent screen. It builds on the now common OLED screens found in smartphones and TVs, but with a transparent display, offers up some new possibilities for Arduino screens.

Take for example this brilliant project that makes use of TOLED displays. By stacking 10 transparent OLED screens in parallel, creator Sean Hodgins has converted a handful of 2D screens into a solid-state volumetric display. This kind of display creates an image that has 3-dimensional depth, taking us one step closer to the neon, holographic screens we imagine in the future.

Crystalfontz has a tiny monochrome (light blue) 1.51" TOLED that has 128x56 pixels. As the technology is more recent than the following displays in this list, the cost is higher too. One of these screens can be purchased for around $26, but for certain applications, it might just be worth it.

The liquid crystal display (LCD) is the most common display to find in DIY projects and home appliances alike. This is no surprise as they are simple to operate, low-powered, and incredibly cheap.

This type of display can vary in design. Some are larger, with more character spaces and rows; some come with a backlight. Most attach directly to the board through 8 or 12 connections to the Arduino pins, making them incompatible with boards with fewer pins available. In this instance, buy a screen with an I2C adapter, allowing control using only four pins.

Available for only a few dollars (or as little as a couple of dollars on AliExpress with included I2C adapter), these simple displays can be used to give real-time feedback to any project.

The screens are capable of a large variety of preset characters which cover most use cases in a variety of languages. You can control your LCD using the Liquid Crystal Library provided by Arduino. The display() and noDisplay() methods write to the LCD, as shown in the official tutorial on the Arduino website.

Are you looking for something simple to display numbers and a few basic characters? Maybe you are looking for something with that old-school arcade feel? A seven-segment display might suit your needs.

These simple boards are made up of 7 LEDs (8 if you include the dot), and work much like normal LEDs with a common Anode or Cathode connection. This allows them to take one connection to V+ (or GND for common cathode) and be controlled from the pins of your Arduino. By combining these pins in code, you can create numbers and several letters, along with more abstract designs—anything you can dream up using the segments available!

Next on our list is the 5110 display, also affectionately known as the Nokia display due to its wide use in the beloved and nigh indestructible Nokia 3310.

These tiny LCD screens are monochrome and have a screen size of 84 x 48 pixels, but don"t let that fool you. Coming in at around $2 on AliExpress, these displays are incredibly cheap and usually come with a backlight as standard.

Depending on which library you use, the screen can display multiple lines of text in various fonts. It"s also capable of displaying images, and there is free software designed to help get your creations on screen. While the refresh rate is too slow for detailed animations, these screens are hardy enough to be included in long-term, always-on projects.

For a step up in resolution and functionality, an OLED display might be what you are looking for. At first glance, these screens look similar to the 5110 screens, but they are a significant upgrade. The standard 0.96" screens are 128 x 64 monochrome, and come with a backlight as standard.

They connect to your Arduino using I2C, meaning that alongside the V+ and GND pins, only two further pins are required to communicate with the screen. With various sizes and full color options available, these displays are incredibly versatile.

For a project to get you started with OLED displays, our Electronic D20 build will teach you everything you need to know -- and you"ll end up with the ultimate geeky digital dice for your gaming sessions!

These displays can be used in the same way as the others we have mentioned so far, but their refresh rate allows for much more ambitious projects. The basic monochrome screen is available on Amazon.

Thin-film-transistor liquid-crystal displays (TFT LCDs) are in many ways another step up in quality when it comes to options for adding a screen to your Arduino. Available with or without touchscreen functionality, they also add the ability to load bitmap files from an on-board microSD card slot.

Arduino have an official guide for setting up their non-touchscreen TFT LCD screen. For a video tutorial teaching you the basics of setting up the touchscreen version, YouTuber educ8s.tv has you covered:

With the touchscreen editions of these screens costing less than $10 on AliExpress, these displays are another great choice for when you need a nice-looking display for your project.

Looking for something a little different? An E-paper (or E-ink depending on who you ask) display might be right for you. These screens differ from the others giving a much more natural reading experience, it is no surprise that this technology is the cornerstone of almost every e-reader available.

The reason these displays look so good is down to the way they function. Each "pixel" contains charged particles between two electrodes. By switching the charge of each electrode, you can influence the negatively charged black particles to swap places with the positively charged white particles.

This is what gives e-paper such a natural feel. As a bonus, once the ink is moved to its location, it uses no power to keep it there. This makes these displays naturally low-power to operate.

This article has covered most options available for Arduino displays, though there are definitely more weird and wonderful ways to add feedback to your DIY devices.

Now that you have an idea of what is out there, why not incorporate a screen into your DIY smart home setup? If retro gaming is more your thing, why not create some retro games on Arduino?

The key to this project"s low power consumption is the usage of a bare ATMEGA chip instead of an Arduino Board. Since Arduino boards use a voltage regulator in order to work with many different voltage levels, they need more power. We don"t need this regulator since we are powering our project from 3AA batteries!

Another little secret is the LowPower library. When we are not measuring the temperature we put Arduino to sleep using the LowPower library. When a bare ATMEGA chip is sleeping it requires only 0.06mA of current!That means that you can have an ATMEGA chip sleeping for over 4 years on 3 AA batteries!

The project wakes up every two minutes. The first thing it does is to enable the photoresistor by writing HIGH to digital pin 6. It reads the value from the photoresistor and it determins if it is day or night. Then it writes LOW to digital pin 6 in order to disable the photoresistor and conserve porer. If it is night we disable the LCD display if it is ON and we go immediately to sleep for two minutes without reading the temperature. There is no need to do so, since the display is off. This way we conserve even more power. If there is enough light, we enable the LCD display if it was disabled, we read the temperature, we display it on the screen and we go to sleep for two minutes. That loop goes on for ever.

(Note: For a follow-up project which uses a larger screen, click here: Building a 3.5 Digit Low Power LCD Module ) Introduction Sometimes a really simple, low power

2. You’re right – the Sharp displays are expensive. Adafruit provides only the display for $45 (which I purchased and used for early prototyping). The NEWT includes the display plus:

That being said… $92 is a lot of money… so I’m all for people building their own – or better yet, building a better version. I’ll add a comment below with links to all the software (device and server side) and hardware designs.

A. I might use a NE555 to send a 1 HZ pulse to the display, and use a different RTC- as long as it was low cost, low power, and supported multiple alarms/timers. Or maybe I’d add a crystal to the ESP32 and use internal RTC (which is super inaccurate w/o an RTC).

C. I think I’d add a legit battery fuel monitor (I use a voltage monitoring chip right now, that goes HIGH when the batt voltage falls below 3.5V). There were few to no LiPO fuel gauge chips in stock when I launched NEWT

If you’ve ever tried to connect an LCD display to an Arduino, you might have noticed that it consumes a lot of pins on the Arduino. Even in 4-bit mode, the Arduino still requires a total of seven connections – which is half of the Arduino’s available digital I/O pins.

The solution is to use an I2C LCD display. It consumes only two I/O pins that are not even part of the set of digital I/O pins and can be shared with other I2C devices as well.

True to their name, these LCDs are ideal for displaying only text/characters. A 16×2 character LCD, for example, has an LED backlight and can display 32 ASCII characters in two rows of 16 characters each.

If you look closely you can see tiny rectangles for each character on the display and the pixels that make up a character. Each of these rectangles is a grid of 5×8 pixels.

At the heart of the adapter is an 8-bit I/O expander chip – PCF8574. This chip converts the I2C data from an Arduino into the parallel data required for an LCD display.

In addition, there is a jumper on the board that supplies power to the backlight. To control the intensity of the backlight, you can remove the jumper and apply external voltage to the header pin that is marked ‘LED’.

If you are using multiple devices on the same I2C bus, you may need to set a different I2C address for the LCD adapter so that it does not conflict with another I2C device.

An important point here is that several companies manufacture the same PCF8574 chip, Texas Instruments and NXP Semiconductors, to name a few. And the I2C address of your LCD depends on the chip manufacturer.

By shorting the solder jumpers, the address inputs are puled LOW. If you were to short all three jumpers, the address would be 0x20. The range of all possible addresses spans from 0x20 to 0x27. Please see the illustration below.

By shorting the solder jumpers, the address inputs are puled LOW. If you were to short all three jumpers, the address would be 0x38. The range of all possible addresses spans from 0x38 to 0x3F. Please see the illustration below.

So your LCD probably has a default I2C address 0x27Hex or 0x3FHex. However it is recommended that you find out the actual I2C address of the LCD before using it.

Connecting an I2C LCD is much easier than connecting a standard LCD. You only need to connect 4 pins instead of 12. Start by connecting the VCC pin to the 5V output on the Arduino and GND to ground.

Now we are left with the pins which are used for I2C communication. Note that each Arduino board has different I2C pins that must be connected accordingly. On Arduino boards with the R3 layout, the SDA (data line) and SCL (clock line) are on the pin headers close to the AREF pin. They are also known as A5 (SCL) and A4 (SDA).

After wiring up the LCD you’ll need to adjust the contrast of the display. On the I2C module you will find a potentiometer that you can rotate with a small screwdriver.

Plug in the Arduino’s USB connector to power the LCD. You will see the backlight lit up. Now as you turn the knob on the potentiometer, you will start to see the first row of rectangles. If that happens, Congratulations! Your LCD is working fine.

To drive an I2C LCD you must first install a library called LiquidCrystal_I2C. This library is an enhanced version of the LiquidCrystal library that comes with your Arduino IDE.

The I2C address of your LCD depends on the manufacturer, as mentioned earlier. If your LCD has a Texas Instruments’ PCF8574 chip, its default I2C address is 0x27Hex. If your LCD has NXP Semiconductors’ PCF8574 chip, its default I2C address is 0x3FHex.

So your LCD probably has I2C address 0x27Hex or 0x3FHex. However it is recommended that you find out the actual I2C address of the LCD before using it. Luckily there’s an easy way to do this, thanks to the Nick Gammon.

But, before you proceed to upload the sketch, you need to make a small change to make it work for you. You must pass the I2C address of your LCD and the dimensions of the display to the constructor of the LiquidCrystal_I2C class. If you are using a 16×2 character LCD, pass the 16 and 2; If you’re using a 20×4 LCD, pass 20 and 4. You got the point!

First of all an object of LiquidCrystal_I2C class is created. This object takes three parameters LiquidCrystal_I2C(address, columns, rows). This is where you need to enter the address you found earlier, and the dimensions of the display.

In ‘setup’ we call three functions. The first function is init(). It initializes the LCD object. The second function is clear(). This clears the LCD screen and moves the cursor to the top left corner. And third, the backlight() function turns on the LCD backlight.

After that we set the cursor position to the third column of the first row by calling the function lcd.setCursor(2, 0). The cursor position specifies the location where you want the new text to be displayed on the LCD. The upper left corner is assumed to be col=0, row=0.

There are some useful functions you can use with LiquidCrystal_I2C objects. Some of them are listed below:lcd.home() function is used to position the cursor in the upper-left of the LCD without clearing the display.

lcd.scrollDisplayRight() function scrolls the contents of the display one space to the right. If you want the text to scroll continuously, you have to use this function inside a for loop.

lcd.scrollDisplayLeft() function scrolls the contents of the display one space to the left. Similar to above function, use this inside a for loop for continuous scrolling.

If you find the characters on the display dull and boring, you can create your own custom characters (glyphs) and symbols for your LCD. They are extremely useful when you want to display a character that is not part of the standard ASCII character set.

CGROM is used to store all permanent fonts that are displayed using their ASCII codes. For example, if we send 0x41 to the LCD, the letter ‘A’ will be printed on the display.

CGRAM is another memory used to store user defined characters. This RAM is limited to 64 bytes. For a 5×8 pixel based LCD, only 8 user-defined characters can be stored in CGRAM. And for 5×10 pixel based LCD only 4 user-defined characters can be stored.

Creating custom characters has never been easier! We have created a small application called Custom Character Generator. Can you see the blue grid below? You can click on any 5×8 pixel to set/clear that particular pixel. And as you click, the code for the character is generated next to the grid. This code can be used directly in your Arduino sketch.

After the library is included and the LCD object is created, custom character arrays are defined. The array consists of 8 bytes, each byte representing a row of a 5×8 LED matrix. In this sketch, eight custom characters have been created.

Remember the pre-iPhone days when cell phones had buttons and you only touched that tiny black and white screen if you needed to clean it? Nokia used these little LCDs in their 3310 and 5110 cell phones.

As technology changed, these displays finally found their new place in the world of DIY. Soon they became popular among hobbyists as these displays are small(only about 1.5″), inexpensive, easy to use, fairly low power and can display text as well as bitmaps.

Thanks to the PCD8544 controller’s versatility, it includes on-chip generation of LCD supply and bias voltages which results in low power consumption making it suitable for power sensitive applications. In a normal state, the LCD consumes as low as 6 to 7mA only.

As per datasheet, this chip operates in the range of 2.7 to 3.3 V and has 3v communication levels. So, for any 5V logic microcontroller like Arduino, some sort of logic level shifting is required (otherwise display may get damaged).

If you want to change the backlight of the LCD, just remove the LCD off the board by pushing the metal clips at the back side. When the screen comes off, you will notice the four LEDs soldered around the edges of the display. Just replace the LEDs with desired color LEDs.

There are many versions of these LCD displays that don’t come with any current limiting resistor. This means you have to be careful while connecting power supply to it. As a precautionary measure, you can place a 330Ω current limiting resistor in series with the ‘Backlight’ pin.

The PCD8544 LCD driver has a built-in 504 bytes Graphic Display Data RAM (GDDRAM) for the screen which holds the bit pattern to be displayed. This memory area is organized in 6 banks (from 0 to 5). Each bank contains 84 columns/segments (from 0 to 83). And each column can store 8 bits of data (from 0 to 7). That surely tells us we have

RST pin resets the display. It’s an active low pin meaning; you can reset the display by pulling it low. You can also connect this pin to the Arduino reset so that it will reset the screen automatically.

BL(Backlight) pin controls the backlight of the display. To control its brightness, you can add a potentiometer or connect this pin to any PWM-capable Arduino pin.

Connections are fairly simple. As we are implementing software SPI, we have flexible pin options. You can connect data transmission pins to any digital I/O pin. In our case the serial clock(CLK), serial data(DIN), data/command(DC), chip enable(CE) and reset(RST) pins are connected from pin 7 all the down to pin 3 on Arduino.

But unfortunately, the LCD has 3v communication levels, so we cannot directly connect these pins to the Arduino. We need some protection. This can be done by shifting levels.

Finally, The backlight(BL) pin is connected to 3.3V via 330Ω current limiting resistor. You can add a potentiometer or connect this pin to any PWM-capable Arduino pin, if you wish to control its brightness.

The PCD8544 LCD controller has flexible yet complex drivers. Vast knowledge on memory addressing is required in order to use the PCD8544 controller. Fortunately, Adafruit’s PCD8544 Nokia 5110 LCD library was written to hide away all the complexities so that we can issue simple commands to control the display.

Filter your search by typing ‘nokia’. There should be a couple entries. Look for Adafruit PCD8544 Nokia 5110 LCD library. Click on that entry, and then select Install.

This library is a hardware-specific library which handles lower-level functions. It needs to be paired with Adafruit GFX Library to display graphics primitives like points, lines, circles, rectangles etc. Install this library as well.

This will give you complete understanding about how to use the Nokia 5110 LCD display and can serve as the basis for more practical experiments and projects. Try the sketch out and then we will dissect it in some detail.

The sketch starts by including three libraries viz. SPI.h, Adafruit_GFX.h and Adafruit_PCD8544.h. Next, we need to create an LCD object. This object takes 5 parameters and specifies which Arduino pins are connected to the LCD’s CLK, Din, D/C, CE and RST pin. We also defined rotatetext variable which will make sense a little later.

In setup function: we need to initialize the LCD object using begin() function. We also need to set the contrast of the display using setContrast(value) function with value can be anywhere between 0-100. However, value between 50-60 gives great results.

For displaying text on the screen, we need to set the font size. This can be done by calling setTextSize() and passing font size (starting from 1) as a parameter.

In order for the library to perform extremely fast mathematical operations on the screen buffer (more than 100 frames per second), calls to the print functions do not immediately transfer the contents of screen buffer to the PCD8544 controller. A display() command is required to instruct the library to perform the bulk transfer from the screen buffer in the ATmega328P to the internal memory of the PCD8544 controller. As soon as the memory is being transferred, the pixels corresponding to the screen buffer will show up on the LCD display.

For displaying inverted text, we will call setTextColor(FontColor,BackgroundColor) function again. If you are paying attention, you know we passed only one parameter to this function earlier, but now we are passing two parameters. This is possible because of something called function overloading. Function overloading is the ability to create multiple functions of the same name but with different set of parameters. Calls to an overloaded function will run a specific implementation of that function depending upon the parameters passed.

Numbers can be displayed on the LCD display by just calling print() or println() function. An overloaded implementation of these functions accepts 32-bit unsigned int, so you can only display numbers from 0 to 4,294,967,295.

The print() & println() functions send data to the display as human-readable ASCII text while write() function sends binary data to the display. So, you can use this function to display ASCII symbols. In our example sending number 3 will display heart symbol.

You can rotate the contents of the display by calling setRotation() function. It allows you to view your display in portrait mode, or flip it upside down.

The function accepts only one parameter that corresponds to 4 cardinal rotations. This value can be any non-negative integer starting from 0. Each time you increase the value, the contents of the display are rotated 90 degrees counter clockwise. For example:0 – Keeps the screen to the standard landscape orientation.

You can draw rectangle on the display by using drawRect() function. The function takes five parameters viz. X coordinate, Y coordinate, Width, Height and color. Actually this function draws hollow rectangle with 1 pixel border. You can draw filled rectangle using fillRect() function.

You can draw round rectangle on the display by using drawRoundRect() function. This function takes same parameters as drawRect() function except one additional parameter – Radius of corner rounding. Actually this function draws hollow round rectangle with 1 pixel border. You can draw filled round rectangle using fillRoundRect() function.

You can draw circle on the display by using drawCircle() function. The function takes four parameters viz. X coordinate of center, Y coordinate of center, radius and color. This function draws hollow circle with 1 pixel border. You can draw filled circle using fillCircle() function.

You can draw triangle on the display by using drawTriangle() function. The function takes seven parameters viz. 3 X & Y coordinates (x0, y0, x1, y1, x2 & y2) of vertices of triangle and color. (X0,y0) represents top vertex, (x1,y1) represents left vertex and (x2,y2) represents right vertex.

This last example shows how to draw bitmap images to the Nokia 5110 LCD Display. This is useful for creating splash screens of company logos, making sprites or just creating fun graphics for displaying information. Copy the following code, paste it into the Arduino IDE and click upload.

To show bitmap image on the Nokia 5110 LCD display we need to call drawBitmap() function. It takes six parameters viz. Top left corner X coordinate, top left corner Y coordinate, byte array of monochrome bitmap, width of bitmap in pixels, height of bitmap in pixels and Color.

But, before we can call the drawBitmap() function, we first need an image to draw. Remember, the screen resolution of Nokia 5110 LCD display is 84×48 pixels, so images larger than that will not display correctly. To get a correctly sized image, you can use your favorite drawing programs like Inkscape, Photoshop, Paint, etc., setting the canvas size to 84×48 pixels.

Once you have a bitmap, it’s time to convert it into an array that the PCD8544 controller can understand. This can be done using two ways: Online method using image2cpp and Offline method using LCD Assistant.

There’s an online application called image2cpp – http://javl.github.io/image2cpp/ which can convert your image into an array. Image2cpp is newer and much more powerful than LCD Assistant (later solution). It will allow you to:

This tool is so powerful that it can work offline as well. Simply save the page to your PC and open it in your browser. Thanks to Jasper van Loenen for his excellent contribution.

Finally, change the most important option – Brightness threshold as per your requirement. Setting threshold will make pixels above this level white and below black. In our case we have set it to 171 to get nice details of Marilyn Monroe.

Once you are satisfied with the outcome, you can proceed generating the data array. Simply select Code output format as Arduino Code and click on Generate code button.

Just for your information, there’s an option called Draw mode. It actually creates image according to the scanning patter of the display. If your image looks all messed up on your display, try changing the mode.

There’s another application called LCD assistant – http://en.radzio.dxp.pl/bitmap_converter/which can convert your bitmap image into data array. It’s not as powerful as image2cpp but still popular among hobbyists.

Just for your information, there’s an option called Byte Orientation. It actually creates image according to the scanning patter of the display. If your image looks all messed up on your display, try changing the mode.

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.

If we take a closer look at the display we can notice that there are small rectangular areas composed of 5×8 pixels grid. Each pixel can light up individually, and so we can generate characters within each grid.

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.

It has 16 pins and the first one from left to right is the Groundpin. The second pin is the VCCwhich we connect the 5 volts pin on the Arduino Board. Next is the Vo pin on which we can attach a potentiometer for controlling the contrast of the display.

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.

Next is the E pin which enables the writing to the registers, or the next 8 data pins from D0 to D7. So through this pins we are sending the 8 bits data when we are writing to the registers or for example if we want to see the latter uppercase A on the display we will send 0100 0001 to the registers according to the ASCII table. The last two pins A and K, or anode and cathode are for the LED back light.

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.

In case we have a text with length greater than 16 characters, we can scroll the text using the scrollDisplayLeft() orscrollDisplayRight() function from the LiquidCrystal library.

We can choose whether the text will scroll left or right, using the scrollDisplayLeft() orscrollDisplayRight() functions. With the delay() function we can set the scrolling speed.

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.

I hope you enjoyed this tutorial and learned something new. Feel free to ask any question in the comments section below and don’t forget to check out my full collection of 30+ Arduino Projects.