using lcd display with arduino brands
Liquid Crystal displays or LCDs have been used in electronics equipment since the late 1970s. LCD displays have the advantage of consuming very little current And they are ideal for your Arduino projects.
In this article and in the accompanying video I’ll show you how easy it is to add an LCD display to your next Arduino design. I’ll also show you a very popular Arduino Shield that has a keypad which you can use in your projects as well.
Today LCD displays are used in a variety of items from test equipment to televisions. They’re inexpensive and versatile, this makes them ideal for all sorts of designs.
LCD displays do not emit light. Instead they block the passage of light, like little windows which open and shut the let light through. The liquid crystals used inside LCD displays are sandwiched between two layers of polarized material. By changing the orientation of the liquid crystals they allow light to pass or they block the light entirely.
Because transmissive LCD displays (the type we will be using) work by blocking light they require a backlight. Several methods have been used to create back lights including electroluminescent panels and fluorescent tubes. these days the most common form of backlight is an LED, in fact so-called LED televisions are usually just LCD screens with an LED backlight system.
Another type of LCD display, the passive-matrix display, does not require a backlight, it works using reflected light. This type of display is often found in digital watches.
The principles of liquid crystals were discovered in the late 1880s but work on Modern LCD displays did not begin until the mid-1960s. a number of patents were filed in the early 1970s and in 1973 the Sharp Corporation introduced LCD displays for calculators.
The first color LCD displays were developed in the early 1980s but production units were not commonly available until the mid-1990s. By the late 1990s LCD displays were quite common.
A number of LCD displays are available for experimenters. These low-cost monochrome displays are ideal for use with microcontrollers like the Arduino and micro computers like the Raspberry Pi.
These displays are available in a number of different configurations. The part number for the display generally relates to the number of rows and columns in the display.
Common display configurations include 16 x 2, 16 x 4 and 20 x 4. All of these displays are used in a virtually identical fashion the only difference being the number of columns and rows they have.
The LCD1602 display module is a very popular and inexpensive LCD display. It is available in a number of different colors such as blue yellow and green and can easily be connected to an Arduino or Raspberry Pi.
In operation data is sent down the parallel data lines for the display. There are two types of data that can be sent to the display. The first type of data are the ASCII characters which are to be displayed on the display. The other type of data are the control characters that are used to activate the various display functions.
Brightness– This is the input for the brightness control voltage, which varies between 0 and 5 volts to control the display brightness. On some modules this pin is labeled V0.
Because the LCD module uses a parallel data input it requires 8 connections to the host microcontroller for the data alone. Add that to the other control pins and it consumes a lot of connections. On an Arduino Uno half of the I/O pins would be taken up by the display, which can be problematic if you want to use the I/O pins for other input or output devices.
We will begin our experiments by hooking up the LCD1602 to an Arduino Uno and running a few of the example sketches included with the Arduino IDE. This will allow you to get familiar with the display without needing to write any code.
We need to hookup our LCD display to our Arduino. The display can use any of the Arduino digital I/O pins as it has no special requirements, but if you hook it up as I’ve illustrated here you can run the example sketches without needing to make any modifications.
In addition to the LCD1602 display ands the Arduino Uno you will need a 10K trimpot ot potentiometer, this is used a s a brightness control for the display. You’ll also need a 220 ohm resistor to drop the voltage for the displays LED backlight.
The Arduino IDE includestheLiquidCrystallibraryand this library has a number of example sketches. I’ll go over three of them here but you can also try the other ones.
The sketch starts with a number of credits and a description of the required hardware hookup. You’ll note that this is the same hookup you just performed on your Arduino and LCD module.
We then initialize an object that we call “lcd” using the pinouts of the LCD display. If you decide to hook up your display to different pins then you’ll need to modify this section.
In the beginning of the loop we set our cursor to the first position in the second row. Note that the row numbers start with zero so the second row is row 1.
That ends the loop, so we start back at the top of the loop and repeat. The result will be a counter on the second line that counts seconds from the htime the Arduino was last reset.
Load the sketch up to your Arduino and observe your display. If you don’t see anything try adjusting the brightness control that you wired to the display.
The second example we will try isthe Scroll sketch. Scrolling is a useful technique when you can’t get your text to fit on one line of the LCD display.
In the loop the code demonstrates the use of thescrollDisplayLeftandscrollDisplayRightfunctions. As their names imply they move the text in a left or right direction.
Finally the last counter moves the text 16 positions to the left again, which will restore it back to the center of the display. The loop then repeats itself.
Custom characters are useful when you want to display a character that is not part of the standard 127-character ASCII character set. Thi scan be useful for creating custom displays for your project.
A character on the display is formed in a 5 x 8 matrix of blocks so you need to define your custom character within that matrix. To define the character you’ll use thecreateCharfunctionof the LiquidCrystal library. You are limited to defining a maximum of eight characters.
To usecreateCharyou first set up an array of bytes with 8 elements. Each element in the array defines one row of the character in the 5 x 8 matrix. You then use createCharto assign a number from 0 to 7 to that array.
The Custom Character demonstration requires one additional component to be wired to the Arduino, a potentiometer (10K or greater) wired up to deliver a variable voltage to analog input pin A0.
As with the previous sketches we examined this one starts by loading theLiquidCrystallibrary and defining an object calledlcdwith the connection information for the display. It then moves on to define the custom characters.
Each character is defined as an array with 8 elements, the zeros and ones in the array indicate which elements in the character should be on and which ones should be off. Five arrays are defined, although the sketch actually only used four of them.
The last two arrays,amsUpandarmsDowndefine the shape of a little “stickman”, or “stickperson” if you want to be politically correct! This is done to show how we can animate a character on the display.
Then the five custom characters are assigned a unique integer using the createChar function. Remember, you can define a maximum of eight custom characters in a sketch.
Finally the setup routine ends by printing a line to the first row of the LCD display. The line makes use of two of the custom characters, the “heart” and the “smiley”.
We begin by reading the value of the voltage on pin A0 using the ArduinoanalogReadfunction. As the Arduino has a 10-bit analog to digital converter this will result in a reading ranging from 0 to 1023.
We then use an Arduinomapfunction to convert this reading into a range from 200 to 1000. This value is then assigned to an integer calleddelayTime, which as its name implies represents a time delay period.
One thing you may have noticed about using the LCD display module with the Arduino is that it consumes a lot of connections. Even in 4-wire mode there are still a total of seven connections made to the Arduino digital I/O pins. As an Arduino Uno has only 14 digital I/O pins that’s half of them used up for the display.
In other cases you would need to resort to using some of the analog pins as digital pins or even moving up to an Arduino Mega which has many more I/O pins.
But there is another solution. Use the I2C bus adapter for the LCD display and connect using I2C. This only consumes two I/O pins and they aren’t even part of the set of digital I/O pins.
The I2C or IIC bus is theInter Integrated Circuitbus. It was developed by Philips Semiconductors in 1982 for use in the television industry. The idea was to allow the integrated circuits in televisions to “talk” to one another using a standard bus.
The bus has evolved to be used as an ideal method of communicating between microcontrollers, integrated circuits, sensors and micro computers. You can use it to allow multiple Arduinos to talk to each other, to interface numerous sensors and output devices or to facilitate communications between a Raspberry Pi and one or more Arduinos.
In I2C communications there is the concept of Master and Slave devices. There can be multiples of each but there can only be one Master at any given moment. In most Arduino applications one Arduino is designated Master permanently while the other Arduinos and peripherals are the Slaves.
The Master transmits the clock signal which determines how fast the data on the bus is transferred. There are several clock speeds used with the I2C bus. The original design used 100 KHz and 400 KHz clocks. Faster rates of 3.4 MHz and higher are available on some I2C configurations.
Every device on the I2C bus has a unique address. When the Master wants to communicate with a Slave device it calls the Slaves address to initiate communications.
The I2C Adapter for the LCD display is a tiny circuit board with 16 male header pins soldered to it. These pins are meant to be connected directly to the 16-pin connection on the LCD1602 display (or onto other displays that use the same connection scheme).
The device also has a 4-pin connector for connection to the I2C bus. In addition there is a small trimpot on the board, this is the LCD display brightness control.
Most of these devices have three jumpers or solder pads to set the I2C address. This may need to be changed if you are using multiple devices on the same I2C bus or if the device conflicts with another I2C device.
Most Arduino Unos also have some dedicated pins for I2C, these are internally connected to A4 and A5 and are usually located above the 14 digital I/O pins. Some models of the Uno have additional I2C connectors as well.
Note how much easier it is to use the I2C connection, which does not consume any of the Arduino Unos 14 digital I/O pins. Since A4 and A5 are being used for the I2C bus they can’t be used as analog inputs in this configuration.
Nick has written a simple I2C scanner sketch that he’s put into the public domain. It scans your I2C bus and gives you back the address of every I2C device it finds. I’ve repeated Nick’s sketch here, it’s also in the ZIP file that you can download with all of the code for this article.
Load this sketch into your Arduino then open your serial monitor. You’ll see the I2C address of your I2C LCD display adapter. You can then make note of this address and use it in the sketches we’ll be looking at now.
In order to run the subsequent sketches you’ll need to install another library. This is theNewLiquidCrystallibrarywhich, as its name implies, is an improved version of the LiquidCrystal library packaged with your Arduino IDE.
The sketch starts by loading the ArduinoWirelibrary. This is the Arduino library that facilitates communications over I2C and it’s part of your Arduino IDE installation.
On the next line we define the connections to the LCD display module from the I2C Adapter,. Note that these are NOT the connections from the Arduino, they are the connections used by the chip on the adapter itself.
In setup we set the size of the display and then print “Hello world!” on the first line in the first position. After a short delay we print “How are you?” on the second line.
Load the sketch and run it on your Arduino. If you can’t get it to work check out the address and connection information to be sure you have it right.
We need to make a minor wiring adjustment to the hookup with our I2C adapter, specifically we will need to add a DHT22 temperature and humidity sensor into the circuit. The wiring is shown here:
As you can see the DHT22 is connected with its output tied to pin 7 of the Arduino. The other two connections are 5 volts and ground. Note that pin 3 of the DHT22 is not used.
This sketch also makes use of theDHTlibrary from Adafruit. We used this library in a previous article, “Using the HC-SR04 Ultrasonic Distance Sensor with Arduino” so you may want to take a look at that one in order to get it installed.
The key thing to note is that this library is dependant upon another Adafruit library, theirUnified Sensorlibrary. Both can be installed using the Library Manager in your Arduino IDE.
The sketch is similar to our demo sketch in that it creates an “lcd” object with the I2C and display connection information. It also defines a couple of parameters for the DHT22 sensor, as well as some floating variables to hold the temperature and humidity values.
Note that this displays the temperature in Celsius. If you want to change this to Fahrenheit its a simple matter of using some math. The formula( temp * 1.8 ) + 32will convert the results to Fahrenheit.
So far we have used the LCD1602 display module for all of our experiments. For our final demonstration we’ll switch to a popular Arduino shield that contains a LCD1602 along with some push buttons.
The LCD Keypad Shield is available from several different manufacturers. The device fits onto an Arduino Uno or an Arduino Mega and simplifies adding an LCD display to your project.
The Reset button is simply connected to the Arduino Reset pin and works just like the Reset button on the Arduino itself. This is common on many shields as the shields physically cover the Reset button.
Instead the buttons are connected to a resistor array that acts as a voltage divider. The entire array is connected to the Arduino’s analog A0 pin. One pin for five push buttons.
Note that the LCD is being used in 4-wire mode. The LCD itself is the same one used on the LCD1602 module, so all of the code for that module will work with the LCD Keypad Shield as well.
Now that you know how the LCD Keypad module works and which Arduino pins it uses all that remains is to install it onto your Arduino and load the demo sketch.
One thing – once the shield is installed on the Arduino you won’t have easy access to the unused I/O pins to connect any sensors or output devices you may want to use (although the demo sketch doesn’t need anything else connected). There are a couple of ways to get around this:
Use a shield that exposes the pins for prototyping before you install the LCD Keypad shield. In the video associated with this article I use a “Screw Shield” that brings all of the Arduino I/O pins out to a series of screw connectors. There are other similar shields. Using one of these shields is the easiest way to work with the LCD Keypad shield, as well as other Arduino shields.
The sketch begins by including theLiquidCrystallibrary. You can use the original one or the one includes with theNewLiquidCrystallibrary. We then set up an object with the LCD connections, note that these are just hard-coded as they won’t change.
Next we define a number of constants, one for each of the push buttons. Note that nothing is defined for the Reset button as it simply mimics the Arduino Reset button, however a constant is defined for the “none” condition.
After that we define a function calledread_LCD_buttons(). This function reads the value on analog port A0 and returns an integer corresponding to the button integers we defined earlier. Note that the function adds approximately 50 to each of the manufacturers specified values to account for intolerances in the resistors in the voltage divider.
We start the loop by placing the cursor 9 spaces over on the second line. We then use themillisfunction to display a counter that counts the time since the Arduino was reset. This is to test the Reset button.
We then call ourread_LCD_buttons()function and use it to display the value of the push button, right before the counter. Then we end the loop and do it again.
Load the code onto the Arduino and run it. You should see the value of each button as you press it, along with a counter that increments each second. If you press Reset the counter should reset itself back to zero.
As you can see LCD displays are pretty simple to use thanks to the availability of some excellent libraries for the Arduino. As these displays are also very inexpensive they will make an ideal addition to many of your Arduino projects.
And finally the LCD Keypad Shield is a convenient method of adding both a display and a simple keypad to your project, no wiring or soldering required.
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.
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.
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.
As discussed earlier in this tutorial a character is made up of a 5×8 pixel matrix, so you need to define your custom character within that matrix. You can use the createChar() function to define a character.
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.
In setup, a custom character is created using the createChar() function. This function takes two parameters. The first parameter is a number between 0 and 7 to reserve one of the 8 supported custom characters. The second is the name of the array.
This website is using a security service to protect itself from online attacks. The action you just performed triggered the security solution. There are several actions that could trigger this block including submitting a certain word or phrase, a SQL command or malformed data.
Hello friend welcome to “Techno-E-Solution” in this article we are going to learn how to connect LCD display with Arduino Uno and print "Hello World!" on LCD using Arduino Uno. The 16x2 LCD is most popular LCD in electronics projects. In upcoming project we need this display in our project so it"s the beginners level tutorial learn this tutorial with fun. So friends let"s get started..........
A PCB Design Problems Detector, An Engineering Solution Provider Import the Gerber file with one click. No need for complicated file reading steps to review easily and improve efficiency.
In this article, you will learn how to use TFT LCDs by Arduino boards. From basic commands to professional designs and technics are all explained here. At the end of this article, you can :Write texts and numbers with your desired font.
In electronic’s projects, creating an interface between user and system is very important. This interface could be created by displaying useful data, a menu, and ease of access. A beautiful design is also very important.
There are several components to achieve this. LEDs, 7-segments, Character and Graphic displays, and full-color TFT LCDs. The right component for your projects depends on the amount of data to be displayed, type of user interaction, and processor capacity.
TFT LCD is a variant of a liquid-crystal display (LCD) that uses thin-film-transistor (TFT) technology to improve image qualities such as addressability and contrast. A TFT LCD is an active matrix LCD, in contrast to passive matrix LCDs or simple, direct-driven LCDs with a few segments.
In Arduino-based projects, the processor frequency is low. So it is not possible to display complex, high definition images and high-speed motions. Therefore, full-color TFT LCDs can only be used to display simple data and commands.
In this article, we have used libraries and advanced technics to display data, charts, menu, etc. with a professional design. This can move your project presentation to a higher level.
Size of displays affects your project parameters. Bigger Display is not always better. if you want to display high-resolution images and signs, you should choose a big size display with higher resolution. But it decreases the speed of your processing, needs more space and also needs more current to run.
After choosing the right display, It’s time to choose the right controller. If you want to display characters, tests, numbers and static images and the speed of display is not important, the Atmega328 Arduino boards (such as Arduino UNO) are a proper choice. If the size of your code is big, The UNO board may not be enough. You can use Arduino Mega2560 instead. And if you want to show high resolution images and motions with high speed, you should use the ARM core Arduino boards such as Arduino DUE.
In electronics/computer hardware a display driver is usually a semiconductor integrated circuit (but may alternatively comprise a state machine made of discrete logic and other components) which provides an interface function between a microprocessor, microcontroller, ASIC or general-purpose peripheral interface and a particular type of display device, e.g. LCD, LED, OLED, ePaper, CRT, Vacuum fluorescent or Nixie.
The display driver will typically accept commands and data using an industry-standard general-purpose serial or parallel interface, such as TTL, CMOS, RS232, SPI, I2C, etc. and generate signals with suitable voltage, current, timing and demultiplexing to make the display show the desired text or image.
The LCDs manufacturers use different drivers in their products. Some of them are more popular and some of them are very unknown. To run your display easily, you should use Arduino LCDs libraries and add them to your code. Otherwise running the display may be very difficult. There are many free libraries you can find on the internet but the important point about the libraries is their compatibility with the LCD’s driver. The driver of your LCD must be known by your library. In this article, we use the Adafruit GFX library and MCUFRIEND KBV library and example codes. You can download them from the following links.
You must add the library and then upload the code. If it is the first time you run an Arduino board, don’t worry. Just follow these steps:Go to www.arduino.cc/en/Main/Software and download the software of your OS. Install the IDE software as instructed.
The second adds a library that supports drivers of MCUFRIEND Arduino display shields.#include "TouchScreen.h" // only when you want to use touch screen#include "bitmap_mono.h" // when you want to display a bitmap image from library#include "bitmap_RGB.h" // when you want to display a bitmap image from library#include "Fonts/FreeSans9pt7b.h" // when you want other fonts#include "Fonts/FreeSans12pt7b.h" // when you want other fonts#include "Fonts/FreeSerif12pt7b.h" // when you want other fonts#include "FreeDefaultFonts.h" // when you want other fonts#include "SPI.h" // using sdcard for display bitmap image#include "SD.h"
By these two functions, You can find out the resolution of the display. Just add them to the code and put the outputs in a uint16_t variable. Then read it from the Serial port by Serial.println();. First add Serial.begin(9600); in setup().
These three blocks of code draw lines like the previous code with 5-pixel thickness.tft.fillRect(x,y,w,h,t);//fillRect(int16_t x, int16_t y, int16_t w, int16_t h, uint16_t t)tft.drawRect(x,y,w,h,t);//drawRect(int16_t x, int16_t y, int16_t w, int16_t h, uint16_t t)tft.fillRoundRect(x,y,w,h,r,t);//fillRoundRect (int16_t x, int16_t y, int16_t w, int16_t h, uint8_t R , uint16_t t)tft.drawRoundRect(x,y,w,h,r,t);//drawRoundRect(int16_t x, int16_t y, int16_t w, int16_t h, uint8_t R , uint16_t t)
The second function just displays the string.showmsgXY(x,y,sz,&FreeSans9pt7b,"www.Electropeak.com");//void showmsgXY(int x, int y, int sz, const GFXfont *f, const char *msg)void showmsgXY(int x, int y, int sz, const GFXfont *f, const char *msg){ uint16_t x1, y1;uint16_t wid, ht;tft.setFont(f);tft.setCursor(x, y);tft.setTextColor(0x0000);tft.setTextSize(sz);tft.print(msg);}
First you should convert your image to hex code. Download the software from the following link. if you don’t want to change the settings of the software, you must invert the color of the image and make the image horizontally mirrored and rotate it 90 degrees counterclockwise. Now add it to the software and convert it. Open the exported file and copy the hex code to Arduino IDE. x and y are locations of the image. sx and sy are sizes of image. you can change the color of the image in the last input.
Upload your image and download the converted file that the UTFT libraries can process. Now copy the hex code to Arduino IDE. x and y are locations of the image. sx and sy are size of the image.
In this template, We just used a string and 8 filled circles that change their colors in order. To draw circles around a static point, You can use sin(); and cos(); functions. you should define the PI number. To change colors, you can use color565(); function and replace your RGB code.#include "Adafruit_GFX.h"#include "MCUFRIEND_kbv.h"MCUFRIEND_kbv tft;#include "Fonts/FreeSans9pt7b.h"#include "Fonts/FreeSans12pt7b.h"#include "Fonts/FreeSerif12pt7b.h"#include "FreeDefaultFonts.h"#define PI 3.1415926535897932384626433832795int col[8];void showmsgXY(int x, int y, int sz, const GFXfont *f, const char *msg){int16_t x1, y1;uint16_t wid, ht;tft.setFont(f);tft.setCursor(x, y);tft.setTextColor(0x0000);tft.setTextSize(sz);tft.print(msg);}void setup() {tft.reset();Serial.begin(9600);uint16_t ID = tft.readID();tft.begin(ID);tft.setRotation(1);tft.invertDisplay(true);tft.fillScreen(0xffff);showmsgXY(170, 250, 2, &FreeSans9pt7b, "Loading...");col[0] = tft.color565(155, 0, 50);col[1] = tft.color565(170, 30, 80);col[2] = tft.color565(195, 60, 110);col[3] = tft.color565(215, 90, 140);col[4] = tft.color565(230, 120, 170);col[5] = tft.color565(250, 150, 200);col[6] = tft.color565(255, 180, 220);col[7] = tft.color565(255, 210, 240);}void loop() {for (int i = 8; i > 0; i--) {tft.fillCircle(240 + 40 * (cos(-i * PI / 4)), 120 + 40 * (sin(-i * PI / 4)), 10, col[0]); delay(15);tft.fillCircle(240 + 40 * (cos(-(i + 1)*PI / 4)), 120 + 40 * (sin(-(i + 1)*PI / 4)), 10, col[1]); delay(15);tft.fillCircle(240 + 40 * (cos(-(i + 2)*PI / 4)), 120 + 40 * (sin(-(i + 2)*PI / 4)), 10, col[2]); delay(15);tft.fillCircle(240 + 40 * (cos(-(i + 3)*PI / 4)), 120 + 40 * (sin(-(i + 3)*PI / 4)), 10, col[3]); delay(15);tft.fillCircle(240 + 40 * (cos(-(i + 4)*PI / 4)), 120 + 40 * (sin(-(i + 4)*PI / 4)), 10, col[4]); delay(15);tft.fillCircle(240 + 40 * (cos(-(i + 5)*PI / 4)), 120 + 40 * (sin(-(i + 5)*PI / 4)), 10, col[5]); delay(15);tft.fillCircle(240 + 40 * (cos(-(i + 6)*PI / 4)), 120 + 40 * (sin(-(i + 6)*PI / 4)), 10, col[6]); delay(15);tft.fillCircle(240 + 40 * (cos(-(i + 7)*PI / 4)), 120 + 40 * (sin(-(i + 7)*PI / 4)), 10, col[7]); delay(15);}}
In this template, We converted a.jpg image to.c file and added to the code, wrote a string and used the fade code to display. Then we used scroll code to move the screen left. Download the.h file and add it to the folder of the Arduino sketch.#include "Adafruit_GFX.h" // Core graphics library#include "MCUFRIEND_kbv.h" // Hardware-specific libraryMCUFRIEND_kbv tft;#include "Ard_Logo.h"#define BLACK 0x0000#define RED 0xF800#define GREEN 0x07E0#define WHITE 0xFFFF#define GREY 0x8410#include "Fonts/FreeSans9pt7b.h"#include "Fonts/FreeSans12pt7b.h"#include "Fonts/FreeSerif12pt7b.h"#include "FreeDefaultFonts.h"void showmsgXY(int x, int y, int sz, const GFXfont *f, const char *msg){int16_t x1, y1;uint16_t wid, ht;tft.setFont(f);tft.setCursor(x, y);tft.setTextSize(sz);tft.println(msg);}uint8_t r = 255, g = 255, b = 255;uint16_t color;void setup(){Serial.begin(9600);uint16_t ID = tft.readID();tft.begin(ID);tft.invertDisplay(true);tft.setRotation(1);}void loop(void){tft.invertDisplay(true);tft.fillScreen(WHITE);tft.drawRGBBitmap(100, 50, Logo, 350, 200);delay(1000);tft.setTextSize(2);for (int j = 0; j < 20; j++) {color = tft.color565(r -= 12, g -= 12, b -= 12);tft.setTextColor(color);showmsgXY(95, 280, 1, &FreeSans12pt7b, "ELECTROPEAK PRESENTS");delay(20);}delay(1000);for (int i = 0; i < 480; i++) {tft.vertScroll(0, 480, i);tft.drawFastVLine(i, 0, 320, 0xffff); // vertical linedelay(5);}while (1);}
In this template, We used draw lines, filled circles, and string display functions.#include "Adafruit_GFX.h"#include "MCUFRIEND_kbv.h"MCUFRIEND_kbv tft;uint16_t ox=0,oy=0;int ave=0, avec=0, avet=0;////////////////////////////////////////////////////////////////void aveg(void){int z=0;Serial.println(ave);Serial.println(avec);avet=ave/avec;Serial.println(avet);avet=avet*32;for (int i=0; i<24; i++){for (uint16_t a=0; a<3; a++){tft.drawLine(avet+a, z, avet+a, z+10, 0xFB21);} // thickfor (uint16_t a=0; a<2; a++){ tft.drawLine(avet-a, z, avet-a, z+10, 0xFB21);} delay(100); z=z+20; } } ////////////////////////////////////////////////////////////////// void dchart_10x10(uint16_t nx,uint16_t ny) { ave+=nx; avec++; nx=nx*32; ny=ny*48; tft.drawCircle(nx, ny, 10, 0x0517); tft.drawCircle(nx, ny, 9, 0x0517); tft.fillCircle(nx, ny, 7, 0x0517); delay (100); ox=nx; oy=ny; } /////////////////////////////////////////////////////////////////////// void dotchart_10x10(uint16_t nx,uint16_t ny) { ave+=nx; avec++; nx=nx*32; ny=ny*48; int plus=0; float fplus=0; int sign=0; int y=0,x=0; y=oy; x=ox; float xmines, ymines; xmines=nx-ox; ymines=ny-oy; if (ox>nx){xmines=ox-nx;sign=1;}elsesign=0;for (int a=0; a<(ny-oy); a++){fplus+=xmines/ymines;plus=fplus;if (sign==1)tft.drawFastHLine(0, y, x-plus, 0xBFDF);elsetft.drawFastHLine(0, y, x+plus, 0xBFDF);y++;delay(5);}for (uint16_t a=0; a<2; a++){tft.drawLine(ox+a, oy, nx+a, ny, 0x01E8);} // thickfor (uint16_t a=0; a<2; a++){tft.drawLine(ox, oy+a, nx, ny+a, 0x01E8);}ox=nx;oy=ny;}////////////////////////////////////////////////////////////////////void setup() {tft.reset();Serial.begin(9600);uint16_t ID = tft.readID();tft.begin(ID);}void loop() {tft.invertDisplay(true);tft.fillScreen(0xffff);dotchart_10x10(3, 0);dotchart_10x10(2, 1);dotchart_10x10(4, 2);dotchart_10x10(4, 3);dotchart_10x10(5, 4);dotchart_10x10(3, 5);dotchart_10x10(6, 6);dotchart_10x10(7, 7);dotchart_10x10(9, 8);dotchart_10x10(8, 9);dotchart_10x10(10, 10);dchart_10x10(3, 0);dchart_10x10(2, 1);dchart_10x10(4, 2);dchart_10x10(4, 3);dchart_10x10(5, 4);dchart_10x10(3, 5);dchart_10x10(6, 6);dchart_10x10(7, 7);dchart_10x10(9, 8);dchart_10x10(8, 9);dchart_10x10(10, 10);tft.setRotation(1);tft.setTextSize(2);tft.setTextColor(0x01E8);tft.setCursor(20, 20);tft.print("Average");int dl=20;for (int i=0;i<6;i++){for (uint16_t a=0; a<3; a++){tft.drawLine(dl, 40+a, dl+10, 40+a, 0xFB21);}dl+=16;}tft.setRotation(0);aveg();while(1);}
In this template, We added a converted image to code and then used two black and white arcs to create the pointer of volumes. Download the.h file and add it to the folder of the Arduino sketch.#include "Adafruit_GFX.h"#include "MCUFRIEND_kbv.h"MCUFRIEND_kbv tft;#include "Volume.h"#define BLACK 0x0000int a = 0,b = 4000,c = 1000,d = 3000;int s=2000;int j, j2;int i, i2;int White;void setup(){Serial.begin(9600);uint16_t ID = tft.readID();tft.begin(ID);tft.invertDisplay(true);tft.setRotation(1);}void loop(void){tft.invertDisplay(true);tft.fillScreen(BLACK);tft.drawRGBBitmap(0, 0, test, 480, 320);White = tft.color565(255, 255, 255);while(1){if (a < s) {j = 14 * (sin(PI * a / 2000));i = 14 * (cos(PI * a / 2000));j2 = 1 * (sin(PI * a / 2000));i2 = 1 * (cos(PI * a / 2000));tft.drawLine(i2 + 62, j2 + 240, i + 62, j + 240, White);j = 14 * (sin(PI * (a-300) / 2000));i = 14 * (cos(PI * (a-300) / 2000));j2 = 1 * (sin(PI * (a-300) / 2000));i2 = 1 * (cos(PI * (a-300) / 2000));tft.drawLine(i2 + 62, j2 + 240, i + 62, j + 240, 0x0000);tft.fillRect(50, 285, 30, 30, 0x0000);tft.setTextSize(2);tft.setTextColor(0xffff);tft.setCursor(50, 285);tft.print(a / 40); tft.print("%");a++;}if (b < s) {j = 14 * (sin(PI * b / 2000));i = 14 * (cos(PI * b / 2000));j2 = 1 * (sin(PI * b / 2000));i2 = 1 * (cos(PI * b / 2000));tft.drawLine(i2 + 180, j2 + 240, i + 180, j + 240, White);j = 14 * (sin(PI * (b-300) / 2000));i = 14 * (cos(PI * (b-300) / 2000));j2 = 1 * (sin(PI * (b-300) / 2000));i2 = 1 * (cos(PI * (b-300) / 2000));tft.drawLine(i2 + 180, j2 + 240, i + 180, j + 240, 0x0000);tft.fillRect(168, 285, 30, 30, 0x0000);tft.setTextSize(2);tft.setTextColor(0xffff);tft.setCursor(168, 285);tft.print(b / 40); tft.print("%");b++;}if (c < s) {j = 14 * (sin(PI * c / 2000));i = 14 * (cos(PI * c / 2000));j2 = 1 * (sin(PI * c / 2000));i2 = 1 * (cos(PI * c / 2000));tft.drawLine(i2 + 297, j2 + 240, i + 297, j + 240, White);j = 14 * (sin(PI * (c-300) / 2000));i = 14 * (cos(PI * (c-300) / 2000));j2 = 1 * (sin(PI * (c-300) / 2000));i2 = 1 * (cos(PI * (c-300) / 2000));tft.drawLine(i2 + 297, j2 + 240, i + 297, j + 240, 0x0000);tft.fillRect(286, 285, 30, 30, 0x0000);tft.setTextSize(2);tft.setTextColor(0xffff);tft.setCursor(286, 285);tft.print(c / 40); tft.print("%");c++;}if (d < s) { j = 14 * (sin(PI * d / 2000)); i = 14 * (cos(PI * d / 2000)); j2 = 1 * (sin(PI * d / 2000)); i2 = 1 * (cos(PI * d / 2000)); tft.drawLine(i2 + 414, j2 + 240, i + 414, j + 240, White); j = 14 * (sin(PI * (d-300) / 2000)); i = 14 * (cos(PI * (d-300) / 2000)); j2 = 1 * (sin(PI * (d-300) / 2000)); i2 = 1 * (cos(PI * (d-300) / 2000)); tft.drawLine(i2 + 414, j2 + 240, i + 414, j + 240, 0x0000); tft.fillRect(402, 285, 30, 30, 0x0000); tft.setTextSize(2); tft.setTextColor(0xffff); tft.setCursor(402, 285); tft.print(d / 40); tft.print("%"); d++;} if (a > s) {j = 14 * (sin(PI * a / 2000));i = 14 * (cos(PI * a / 2000));j2 = 1 * (sin(PI * a / 2000));i2 = 1 * (cos(PI * a / 2000));tft.drawLine(i2 + 62, j2 + 240, i + 62, j + 240, White);j = 14 * (sin(PI * (a+300) / 2000));i = 14 * (cos(PI * (a+300) / 2000));j2 = 1 * (sin(PI * (a+300) / 2000));i2 = 1 * (cos(PI * (a+300) / 2000));tft.drawLine(i2 + 62, j2 + 240, i + 62, j + 240, 0x0000);tft.fillRect(50, 285, 30, 30, 0x0000);tft.setTextSize(2);tft.setTextColor(0xffff);tft.setCursor(50, 285);tft.print(a / 40); tft.print("%");a--;}if (b > s) {j = 14 * (sin(PI * b / 2000));i = 14 * (cos(PI * b / 2000));j2 = 1 * (sin(PI * b / 2000));i2 = 1 * (cos(PI * b / 2000));tft.drawLine(i2 + 180, j2 + 240, i + 180, j + 240, White);j = 14 * (sin(PI * (b+300) / 2000));i = 14 * (cos(PI * (b+300) / 2000));j2 = 1 * (sin(PI * (b+300) / 2000));i2 = 1 * (cos(PI * (b+300) / 2000));tft.drawLine(i2 + 180, j2 + 240, i + 180, j + 240, 0x0000);tft.fillRect(168, 285, 30, 30, 0x0000);tft.setTextSize(2);tft.setTextColor(0xffff);tft.setCursor(168, 285);tft.print(b / 40); tft.print("%");b--;}if (c > s) {j = 14 * (sin(PI * c / 2000));i = 14 * (cos(PI * c / 2000));j2 = 1 * (sin(PI * c / 2000));i2 = 1 * (cos(PI * c / 2000));tft.drawLine(i2 + 297, j2 + 240, i + 297, j + 240, White);j = 14 * (sin(PI * (c+300) / 2000));i = 14 * (cos(PI * (c+300) / 2000));j2 = 1 * (sin(PI * (c+300) / 2000));i2 = 1 * (cos(PI * (c+300) / 2000));tft.drawLine(i2 + 297, j2 + 240, i + 297, j + 240, 0x0000);tft.fillRect(286, 285, 30, 30, 0x0000);tft.setTextSize(2);tft.setTextColor(0xffff);tft.setCursor(286, 285);tft.print(c / 40); tft.print("%");c--;}if (d > s) {j = 14 * (sin(PI * d / 2000));i = 14 * (cos(PI * d / 2000));j2 = 1 * (sin(PI * d / 2000));i2 = 1 * (cos(PI * d / 2000));tft.drawLine(i2 + 414, j2 + 240, i + 414, j + 240, White);j = 14 * (sin(PI * (d+300) / 2000));i = 14 * (cos(PI * (d+300) / 2000));j2 = 1 * (sin(PI * (d+300) / 2000));i2 = 1 * (cos(PI * (d+300) / 2000));tft.drawLine(i2 + 414, j2 + 240, i + 414, j + 240, 0x0000);tft.fillRect(402, 285, 30, 30, 0x0000);tft.setTextSize(2);tft.setTextColor(0xffff);tft.setCursor(402, 285);tft.print(d / 40); tft.print("%");d--;}}}
In this template, We just display some images by RGBbitmap and bitmap functions. Just make a code for touchscreen and use this template. Download the.h file and add it to folder of the Arduino sketch.#include "Adafruit_GFX.h" // Core graphics library#include "MCUFRIEND_kbv.h" // Hardware-specific libraryMCUFRIEND_kbv tft;#define BLACK 0x0000#define RED 0xF800#define GREEN 0x07E0#define WHITE 0xFFFF#define GREY 0x8410#include "images.h"#include "Fonts/FreeSans9pt7b.h"#include "Fonts/FreeSans12pt7b.h"#include "Fonts/FreeSerif12pt7b.h"#include "FreeDefaultFonts.h"int a = 3000;int b = 4000;int j, j2;int i, i2;void showmsgXY(int x, int y, int sz, const GFXfont *f, const char *msg){int16_t x1, y1;uint16_t wid, ht;// tft.drawFastHLine(0, y, tft.width(), 0xffff);tft.setFont(f);tft.setCursor(x, y);tft.setTextColor(WHITE);tft.setTextSize(sz);tft.print(msg);delay(1000);}void setup(){Serial.begin(9600);uint16_t ID = tft.readID();tft.begin(ID);tft.invertDisplay(true);tft.setRotation(1);}void loop(void){tft.invertDisplay(true);tft.fillScreen(BLACK);tft.drawRGBBitmap(0, 0, test, 480, 320);tft.drawBitmap(20, 20, Line1, 45, 45, 0xffff);//batterytft.drawBitmap(65, 20, Line2, 45, 45, 0xffff);//wifitft.drawBitmap(125, 25, Line3, 45, 45, 0xffff);//mailtft.drawBitmap(185, 25, Line4, 45, 45, 0xffff);//instagramtft.drawBitmap(245, 25, Line6, 45, 45, 0xffff);//powertft.drawBitmap(20, 260, Line5, 45, 45, 0xffff);//twittertft.drawBitmap(410, 140, Line7, 45, 45, 0xffff);//raintft.setTextSize(6);tft.setTextColor(0xffff);tft.setCursor(280, 210);tft.print("20:45");tft.setTextSize(2);tft.setTextColor(0xffff);showmsgXY(330, 280, 1, &FreeSans12pt7b, "Saturday");showmsgXY(300, 305, 1, &FreeSans12pt7b, "6 October 2018");while (1);}
×SPECIAL OFFER (VALID UNTIL NOVEMBER 1ST 2018): If you order the 3.5″ LCD from ElectroPeak, our technical staff will design your desired template for free! Just send an email to info@electropeak.Com containing your order number and requirements ;)
The LCDduino board enables users to create many applications/projects that require a 16×2 LCD display and Arduino. The board has the exact size of 16×2 LCD and can be installed on the backside of the LCD. This is a low-cost solution that has onboard Arduino + LCD so no extra Arduino Nano or Arduino board is required. The Arduino compatible hardware includes onboard programming and boot-loader connectors, Atmega328 microcontroller, and 16×2 LCD interface. Each Arduino I/O Pin including the VCC and GND is exposed to the connectors for easy connection with sensors and other devices. The board enables the easy interface of many devices and sensors. The operating power supply is 7 to 15V DC.
After the board assembly, the brand new Atmega328 microcontroller requires burning the bootloader before it can be programmed using Arduino IDE. Refer to the connection diagram and follow the links below to learn more about bootloader and Arduino IDE programming.
Arduino example code is provided below to test the project. This code will help you to convert this board into a 0 to 5V Voltmeter. Just connect the DC source at analog in A0 to measure the DC voltage.
This website is using a security service to protect itself from online attacks. The action you just performed triggered the security solution. There are several actions that could trigger this block including submitting a certain word or phrase, a SQL command or malformed data.
This website is using a security service to protect itself from online attacks. The action you just performed triggered the security solution. There are several actions that could trigger this block including submitting a certain word or phrase, a SQL command or malformed data.
In this digital age, we come across LCDs all around us from simple calculators to smartphones, computers and television sets, etc. The LCDs use liquid crystals to produce images or texts and are divided into different categories based on different criteria like type of manufacturing, monochrome or colour, and weather Graphical or character LCD. In this tutorial, we will be talking about the 16X2 character LCD Modules.
The 16x2 LCDs are very popular among the DIY community. Not only that, but you can also find them in many laboratory and industrial equipment. It can display up to 32 characters at a time. Each character segment is made up of 40 pixels that are arranged in a 5x8 matrix. We can create alphanumeric characters and custom characters by activating the corresponding pixels. Here is a vector representation of a 16x2 LCD, in which you can see those individual pixels.
As the name indicates, these character segments are arranged in 2 lines with 16 characters on each line. Even though there are LCDs with different controllers are available, The most widely used ones are based on the famous HD44780 parallel interface LCD controller from Hitachi.
Vo / VEE 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.
The 16x2 LCD modules are popular among the DIY community since they are cheap, easy to use and most importantly enable us to provide information very efficiently. With just 6 pins, we can display a lot of data on the display.
The module has 16 pins. Out of these 16 pins, two pins are for power, two pins are for backlight, and the remaining twelve pins are for controlling the LCD.
If you look at the backside of the module you can simply see that there are not many components. The main components are the two controller chips that are under the encapsulation. There is an onboard current limiting resistor for the backlight. This may vary from different modules from different manufacturers. The only remaining components are a few complimentary resistors for the LCD controller.
In the module PCB, you may have noticed some unpopulated footprints. These footprints are meant for charge pump circuits based on switched capacitor voltage converters like ICL7660 or MAX660. You can modify your LCD to work with 3.3V by populating this IC and two 10uF capacitors to C1 and C2 footprint, removing Jumper J1 and adding jumper J3. This modification will generate a negative contrast voltage of around 2.5V. This will enable us to use the LCD even with a VCC voltage of 3.3V.
To test whether a 16x2 LCD works or not, connect the VDD, GND and backlight pins to 5v and GND. Connect the centre terminal of a 10K variable resistor to the VEE pin. Connect the other two terminals to VCC and GND. Simply rotate the variable resistor you will see that the contrast will be adjusted and small blocks are visible. If these rectangles are visible, and you were able to adjust the contrast, then the LCD is working
There are 16 pins on the display module. Two of them are for power (VCC, GND), one for adjusting the contrast (VEE), three are control lines (RS, EN, R/W), eight pins are data lines(D0-D7) and the last two pins are for the backlight (A, K).
The 16x2 LCD has 32 character areas, which are made up of a 5x8 matrix of pixels. By turning on or off these pixels we can create different characters. We can display up to 32 characters in two rows.
Yes, we can. We can store up to eight custom characters in the CGRAM (64 bytes in size) area. We can create load the matrix data for these characters and can recall when they need to be displayed.
Controlling the LCD module is pretty simple. Let’s walk through those steps. To adjust the contrast of the LCD, the Vo/ VEE pin is connected to a variable resistor. By adjusting the variable resistor, we can change the LCD contrast.
The RS or registry select pin helps the LCD controller to know whether the incoming signal is a control signal or a data signal. When this pin is high, the controller will treat the signal as a command instruction and if it’s low, it will be treated as data. The R/W or Read/Write pin is used either to write data to the LCD or to read data from the LCD. When it’s low, the LCD module will be in write mode and when it’s high, the module will be in reading mode.
The Enable pin is used to control the LCD data execution. By default, this pin is pulled low. To execute a command or data which is provided to the LCD data line, we will just pull the Enable pin to high for a few milliseconds.
To test the LCD module, connect the VDD, GND, and backlight pins to 5v and GND. Connect the center terminal of a 10K variable resistor to the VEE pin. Connect the other two terminals to VCC and GND as per the below connection diagram-
Simply rotate the variable resistor you will see that the contrast will be adjusted and small blocks are visible. If these rectangles are visible, and you were able to adjust the contrast, then the LCD is working.
Let’s see how to connect the LCD module to Arduino. For that first, connect the VSS to the GND and VDD to the 5V. To use the LCD backlight, connect the backlight Anode to the 5V and connect the backlight cathode to the GND through a 220Ωresistor. Since we are not using the read function connect the LCD R/W pin to the GND too. To adjust the contrast, connect the centre pin of a 10KΩ trimmer resistor to the VEE pin and connect the side pins to the VCC and GND. Now connect the registry select pin to D12 and Enable pin to D11.
Now let’s connect the data pins. The LCD module can work in two modes, 8-bit and 4-bit. 8-bit mode is faster but it will need 8 pins for data transfer. In 4-bit mode, we only need four pins for data. But it is slower since the data is sent one nibble at a time. 4-bit mode is often used to save I/O pins, while the 8-bit mode is used when speed is necessary. For this tutorial, we will be using the 4-bit mode. For that connect the D4, D5, D6 and D7 pins from the LCD to the D5, D4, D3 and D2 pins of the Arduino.
Here is the actual circuit. It is built as per the connection diagram provided. All the connections are made using standard male to male jumper wires.
The following Arduino 16x2 LCD code will print Hello, World! on the first line of the display and the time the Arduino was running in seconds on the second line.
Now let’s discuss the code. As usual, the sketch starts by including the necessary libraries. For this tutorial, we will be including the LiquidCrystal library from Arduino. This library is compatible with LCDs based on the Hitachi HD44780, or any compatible chipset. You can find more details about this library on the Arduino website.
Let’s create an object to use with the LiquidCrystal library. The following line of code will create an object called lcd. We will be using this object in the entire code to access the library functions. The object is initialized with the pin numbers.
Now let’s look at the setup()function. The lcd.begin function is used to initialize the LCD module. This function will send all the initialization commands. The parameters used while calling this function are the number of columns and the number of rows. And the next function is lcd.print. with this function, we have printed the word Circuit Digest! to the LCD. Since the LCD cursor is set to home position within the lcd.begin, we don’t need to set any cursor position. This text will stay there for two seconds. After that, the text will scroll from left to right until the entire text is out of the display. To scroll the display to the right, we have used the function lcd.scrollDisplayRight. After that, to clear display, we used lcd.clear, this will clear any characters on the display.
Now let’s look at theloop function. The for loop will count from 0 to 9, and when it reaches 9, it will reset the count and repeat the process all over again. lcd.setCursor is used to set the cursor position. lcd.setCursor(8, 1) will set the LCD cursor to the eighth position in the second row. In the LCD, the first row is addressed as 0 and the second row is addressed as 1. And the lcd.print(i) will print the count value stored in the variable i to the display.
Wrong characters are displayed: This problem occurs usually when the LCD is not getting the correct data. Make sure you are sending the correct ASCII value. If you are sending the correct ASCII characters, but still showing the wrong one on the LCD, check your connections for loose contact or short circuits.
Display shows Black boxes or does not show anything: First thing to do in these situations is to adjust the contrast voltage by rotating the variable resistor. This will correct the contrast value and will give you a visible readout.
Contrast is Ok, but still no display: Make sure to provide a sufficient time delay in between sending each character. Because if you don’t give enough time to process the data the display will malfunction.
Contrast and delay are ok, but still no display: Make sure you are powering the LCD from a 5V source. By default, these displays won’t work with a supply voltage below 5V. So if you are using the display with a 3.3V microcontroller make sure to power the display from 5V and use level shifters in between the display and the microcontroller.
In this project we will provide the input voice using Google Voice Keyboard via a Android App (BlueTerm) and print the text on 16x2 LCD using Raspberry Pi.
In this tutorial we are interfacing a Liquid Crystal Display (LCD) module with the Raspberry Pi Pico using Micropython to display strings, and characters on the LCD.
We used some Python scripts to find the local IP address of your Raspberry Pi on the network and display it on the 16x2 LCD Screen. We also added the script in the Crontab so that it can be run on every 10 minutes and we will have the updated IP address every time.
Today, among the various projects with Arduino used in the market, those that involve integration with LCD displays for the display of information stand out.
In this case, the I2C module needs to be connected to the display to have all its communication reduced to four wires: two for power and two for signal.
In order not to make a mistake in the numbering of the pinout, it is important to carefully observe the characteristics of each pin and their locations on the Arduino.
Meanwhile, pin 5 (R/W), connected to GND, demonstrates the read and write signal of the display, and pin 6 (E) serves to enable or disable the signal.
In addition, pins 15 (LED+) and 16 (LED-) will be responsible for supplying power to the LEDs at the bottom of the display. It is possible to connect pin 15 using:Using 2 resistors of 220 ohms in parallel;
With the proper connections, it"s time to program the Arduino by connecting it to the computer and opening the official Arduino IDE in its updated version.
Furthermore, despite being highly efficient, LCD technology is not new to the market, which lowers its cost in relation to other displays with similar benefits.
Arduinos are popular microcontroller boards and a common desired functionality is to use them to drive LCD screens, usually to relay information to the user. In this tutorial, I will teach you how to use the Adafruit I2C/SPI LCD Backpack with an Arduino microcontroller board to drive a LCD.
LCDs require many connections to a driver to work. Managing all these connections all the time can become both cumbersome and annoying. Luckily, Adafruit has made an I2C/SPI LCD Backpack that works with most LCDs. This backpack conveniently reduces the number of connections between your microcontroller and the LCD to 4.
I always like to make a wiring diagram (Figure 1: Arduino-LCD Schematic) using Fritzing, an open-sources schematic capture and PCB routing software. You can download Fritzing using the following link (optional): http://fritzing.org/home/
Pin 1 on the LCD goes to Pin 1 on the LCD Backpack. The rest of the pins are wired sequentially. This can be done on a breadboard or the backpack can be soldered to LCD as I have done.
I2C and SPI are two very popular serial interface buses. This tutorial covers interfacing your Arduino to the LCD Backpack using I2C, but the LCD Backpack can interface with SPI too. You can set the I2C address (A0, A1, A2) or enable SPI (SPI Enable) by jumpering the solder jumpers on the backpack (Figure 2: Solder Jumpers on LCD Backpack). The only circuit using I2C in the tutorial is the LCD Backpack, so we do not need to change the current configurations. This means the LCD Backpack will have an I2C address of 0 (0x00).
To interface the LCD Backpack to the Arduino, connect 5V and a ground pin on the Arduino to the 5V and ground pin on the LCD Backpack. This will provide the LCD and LCD Backpack with power. Note: The LCD requires 5V minimum to work properly. The next two connections are serial data and serial clock. The serial clock connection (orange wire) is between the SCL pin on the Arduino and the CLK pin on the backpack. The serial data connection (blue wire) is between the SDA pin on the Arduino and the DAT pin on the backpack.
The first part of the code is to include the Adafruit_LiquidCrystal header file. This allows you to use the functions in this library. Because the Adafruit_LiquidCrystal library is automatically downloaded with Arduino IDE, this tutorial doesn’t cover downloading Arduino libraries.
Before writing to the LCD, it needs to be initialized. The “begin” function does this by telling the LCD Backpack how many characters are on the display. Since the LCD I am using has a backlight, I also turn the backlight on.
Now that the LCD is initialized, I write “Test Code” to check that everything is working. This code sets the cursor to a starting position, writes “Test” to the display, waits 2 seconds, and then clears the display.
The loop part of the code uses the millis() function and divides by 1000 to compute how long the program has been running. The code then uses the print and setCursor functions to display the program time across the LCD. The loop then waits a second before repeating.
Upload the code to the Arduino. Make sure the Arduino is connected using the 9V Power Adapter because power over USB is not sufficient to power both the Arduino and the LCD display. Once the program begins you should see “Test” across the LCD display as the program runs through setup (Figure 2: LCD Displaying “Test”). When the program loop begins you will see the time program displayed and updating every second (Figure 3: LCD Display Program Runtime – 8(s)). Congrats! You now have an easy-to-use LCD screen for your Arduino board and can use it as a display for future projects. A tip to keep in mind: I2C is a slow bus and if you are constantly updating your LCD you will take time away from the controller performing other tasks.
This website is using a security service to protect itself from online attacks. The action you just performed triggered the security solution. There are several actions that could trigger this block including submitting a certain word or phrase, a SQL command or malformed data.
The previous article that you will find here included a description of the LCD display module. In it we show how to connect the screen to the Arduino UNO board and the basics of its operation with the program. Let"s admit, however, that the screen itself will not find many applications in many devices, because such a simple LCD module does not allow setting settings. A keyboard is necessary for this purpose, and although we will discuss it in more detail in one of the following articles, we will now use a ready-to-use solution from the Arduino ecosystem – Olimex-brande