20x4 i2c character lcd display quotation
ERM2004FS-3 is small size 20 characters wide,4 rows character lcd module,SPLC780C controller (Industry-standard HD44780 compatible controller),6800 4/8-bit parallel interface,single led backlight with white color included can be dimmed easily with a resistor or PWM,fstn-lcd positive,black text on the white color,high contrast,wide operating temperature range,wide view angle,rohs compliant,built in character set supports English/Japanese text, see the SPLC780C datasheet for the full character set, It"s optional for pin header connection,5V or 3.3V power supply and I2C adapter board for arduino.
ERM2004FS-2 is 20 characters wide,4 rows character lcd module,SPLC780C controller (Industry-standard HD44780 compatible controller),6800 4/8-bit parallel interface,single led backlight with white color included can be dimmed easily with a resistor or PWM,fstn-lcd positive,black text on the white color,high contrast,wide operating temperature range,wide view angle,rohs compliant,built in character set supports English/Japanese text, see the SPLC780C datasheet for the full character set. It"s optional for pin header connection,5V or 3.3V power supply and I2C adapter board for arduino.
On previous tutorials on our website, we have covered the use of several displays, LCDs, and TFTs, with diverse Arduino boards. From Nokia 5110 LCD display to different types of OLEDs, the reason for the tutorials has been to ensure that, as a reader, you know how to use many of the most popular displays so this help you make the best choice when trying to select the perfect display for your project. For today’s tutorial, we will continue in that line and examine how to use the 20×4 I2C Character LCD Display with Arduino.
The 20×4 LCD display is essentially a bigger (increased number of rows and columns) version of the 16×2 LCD display with which we have built several projects. The display has room to display 20 columns of characters on 4 rows which makes it perfect for displaying a large amount of text without scrolling. Each of the columns has a resolution of 5×8 pixels which ensures its visibility from a substantial distance. Asides its size, the interesting thing about this version of the display being used for today’s tutorial is the fact that it communicates via I2C, which means we will only require 2 wires asides GND and VCC to connect the display to the Arduino. This is possible via the Parallel to I2C module coupled to the display as shown in picture below. The I2C module can also be bought individually, and coupled to the 16 pins version of the display.
To demonstrate how to use this display, we will build a real-time clock which will display date and time on the LCD. To generate and keep track of date and time, we will use the DS3231 Real time clock. We covered the use of the DS3231 RTC module in the tutorial on DS3231 based Real-time Clock, you can check it out to learn more about its use with the Arduino.
Since the display and the real-time clock are both I2C devices, they will be connected to the same pins on the Arduino. For the Arduino Uno, the I2C pins are located on Pin A5 (SCL) and A4 (SDA). This may differ on any of the other Arduino boards. Connect the components as shown in the schematics below;
To write the code for this project, we will use three main libraries; the DS1307 Library to easily interface with the DS3231 module, the liquid crystal I2C library to easily interface with the LCD display, and the Wire library for I2C communication. While the Wire library comes built into the Arduino IDE, the other two libraries can be downloaded and installed via the links attached to them.
As mentioned during the introduction, our task for today is to obtain time and date information from the RTC module and display on the LCD. As usual, I will do a breakdown of the code and try to explain some of the concepts within it that may be difficult to understand.
We start the code by including the libraries that will be used. After which we create an object of the Liquid crystal library, with the I2C address of the LCD as an argument. The I2C address can be obtained from the seller or as described in our tutorial on using the 16×2 LCD display to ESP32.
Next, we create a set of variables which comprises of byte arrays that represent custom characters to be created and displayed. The custom characters are usually 5pixels in width and 8 pixels in height, representing each box in the rows or columns of the LCD. The byte array represents which pixels of the box to be turned on or off.
Next, we write the void setup function and start by initializing the library using the lcd.begin() function, with the first argument representing the number of columns, and the second argument representing the number of rows. After this, the CreateCustomCharacters() function is called to convert the char variables created above into characters that can be displayed on the LCD. One of the characters created is then used to create a UI/frame which is displayed using the printFrame() function.
The first function is the printTime() which breaks down the time data stored in the “tm” variable to extract seconds, minutes and hour values. These values are then displayed on the LCD using the lcd.print() function.
The printDate function is similar to the printTime function. It extracts date information from the variable tm and uses the lcd.print() function to display it.
Other functions include the createCustomCharacters() and the printFrame() functions. The createCustomCharacters() function, as the name implies, is used to create custom characters using byte arrays. The function takes two arguments; the character number, and the variable to in which the byte array for that character is stored. Only 7 characters can be created at once as such the character number is usually between 1 and 7.
The printFrame() function, on the other hand, was used to create a sort of user interface for the project. it makes use of the characters created above. Each of the custom characters created is displayed using the lcd.write(byte(x)) function with x being the character number of the character to be displayed. The characters are positioned on the LCD using the lcd.setCursor() function which takes numbers representing the column and row on which the character is to be displayed, as arguments.
Different projects, come with different screen requirements. If you need to display a large amount of information and the size is not a constraint, the 20×4 I2C display is definitely one of the options you should consider.
This article includes everything you need to know about using acharacter I2C LCD with Arduino. I have included a wiring diagram and many example codes to help you get started.
In the second half, I will go into more detail on how to display custom characters and how you can use the other functions of the LiquidCrystal_I2C library.
Once you know how to display text and numbers on the LCD, I suggest you take a look at the articles below. In these tutorials, you will learn how to measure and display sensor data on the LCD.
Each rectangle is made up of a grid of 5×8 pixels. Later in this tutorial, I will show you how you can control the individual pixels to display custom characters on the LCD.
They all use the same HD44780 Hitachi LCD controller, so you can easily swap them. You will only need to change the size specifications in your Arduino code.
The 16×2 and 20×4 datasheets include the dimensions of the LCD and you can find more information about the Hitachi LCD driver in the HD44780 datasheet.
After you have wired up the LCD, you will need to adjust the contrast of the display. On the I2C module, you will find a potentiometer that you can turn with a small screwdriver.
The LiquidCrystal_I2C library works in combination with the Wire.h library which allows you to communicate with I2C devices. This library comes pre-installed with the Arduino IDE.
*When using the latest version of the LiquidCrystal_I2C library it is no longer needed to include the wire.h library in your sketch. The other library imports wire.h automatically.
Note that counting starts at 0 and the first argument specifies the column. So lcd.setCursor(2,1) sets the cursor on the third column and the second row.
Next the string ‘Hello World!’ is printed with lcd.print("Hello World!"). Note that you need to place quotation marks (” “) around the text since we are printing a text string.
The example sketch above shows you the basics of displaying text on the LCD. Now we will take a look at the other functions of the LiquidCrystal_I2C library.
This function turns on automatic scrolling of the LCD. This causes each character output to the display to push previous characters over by one space.
If the current text direction is left-to-right (the default), the display scrolls to the left, if the current direction is right-to-left, the display scrolls to the right.
I would love to know what projects you plan on building (or have already built) with these LCDs. If you have any questions, suggestions or if you think that things are missing in this tutorial, please leave a comment down below.
2012 latest IIC LCD2004-character LCD display module, a new high-quality 4 line 20 character LCD module not only set the contrast control knob selector switch also has a backlight and IIC communication interface. For Arduino beginners, not for the cumbersome and complex LCD driver circuit connection and a headache, the real significance of this LCD module will simplify the circuit, this module directly into the Arduino Sensor Shield V5.0 sensor expansion board IIC device interface can, GM 4P sensor connection cable, programmed through the Arduino controller, you can easily identify the slogan, sensor data records.
Everyone loves character LCD, is cheap and works out of box! This is 20x4 character LCD module. But the need for 6 to 10 GPIOs is the pain :) It takes most of GPIO of Arduino and other microcontroller. Now with this I2C or Two wires interface LCD, you will save a lot of GPIO for your sensor and motor control.
LCD shield after connected with a certain sensors or SD card. However, with this I2C interface LCD module, you will be able to realize data display via only 2 wires. If you already has I2C devices in your project, you can still program this LCD with the correct I2C address. It is fantastic for Arduino based project.
The PCF8574 style of I2C LCD adapter requires 5 bytes per LCD command / data operation. There is little point in sending a block of characters. I doubt if it is much faster than one chacter at a time.
The worst i2c LCD libraries are those from adafruit which send multiple bytes for every single signal on the LCD since they are treating the i/o expander port interface as a pseudo digitalWrite()/digitalRead() interface.
Transferring more bytes per i2c transaction can help as the over i2c overhead is reduced START and STOP times plus the i2c address byte for i2c increase the overhead and if they can be avoided, it can help.
Unfortunately, the print() interface in Arduino is single character to the lower layers, so it isn"t possible to use print() to send multiple characters to the lower library to try to speed transfers to the display.
This allows the things like CPU overhead and i2c transfer time to reduce any needed command execution delay all the way down to zero if those other overheads were longer than the LCD command execution.
This will cause the i2c h/w in the AVR to run just a tiny bit faster as rise time will be shorter and the chip will see bus signals just a tiny bit faster.
We offer character LCDs and graphic LCDs as modules or COG (Chip On Glass) displays in a wide array of character and pixel configuration sizes. From yellow/green, red, orange, green, blue, amber, white, and RGB backlight colors to displays without a backlight, we have the perfect LCD for your application.
I"m just trying to print a string onto an LCD display (SparkFun 20x4 SerLCD - RGB Backlight Qwiic). The address of the I²C device is 0x72. I"m using an Arduino Teensy to communicate with the LCD display.
In the attached image lcd.init() just prints the characters up to the 11!! and when the lcd.print("2") is used it printed the random characters and also the 11!!. I"m not sure where to go from here, any help is greatly appreciated. Image of LCD display
Hi, i have and LCD 16x2 connected to my Leonardo. I works properly with all the examples son the connection is ok. But I add the LCD to another sketch and it"s just showing garbage, and i have no idea why. I just want to show "Writing:" in the first row, and the variable nombrearchivo in the second row. All of this works using serial, so my only problem is the LCD.
In 4 bit mode, the host and the LCD must remain in nibble sync. If they lose nibble sync with each other, it will never recover so the LCD will start to see garbage commands.
So if the library is in 4 bit mode and you power cycle only the LCD, the host (arduino) and the LCD will not be in the same mode (LCD in 8 bit mode, host in 4 bit mode) and the LCD will see garbage commands.
In 8 bit mode, it is still possible to get glitches on the display, but since things are done byte at a time there is no nibble synchronization issue so any effects of noise should be short lived and future commands to the LCD should continue to work.
The lcd.clear function is slow and can lead to screen flicker especially if done every time through loop(). Overwrite old data with spaces, reset the cursor position and print the new data and only update the screen when the data changes will help prevent flicker.
I"m tearing my hair out trying to get my project to work. I have an Arduino Uno R3 clone (Freetronics 100% compatible) with a 20x4 I2C LCD from DX (part number GY-LCD-V1). I also have four pushbuttons connected via the analog pins (in digital mode.) Other than that I have nothing connected to the arduino other than power via USB to my Mac.
Initially I thought this might be a memory problem. The sketch is big (about 28KB compiled without debug/info defines) and very nearly 32Kb with them compiled in. Free RAM is about 800bytes according to the debug statements. I"ve been mounting the hardware (LCD + buttons so far) in an enclosure, and I had a few days of the sketch running flawlessly, but now it"s back to the normal problems.
In the previous tutorial, we discussed scrolling long text strings on a character LCD using Arduino. However, it’s also possible to display custom characters on the LCD. These custom characters are user-defined and are stored in Character Generator RAM (CGRAM) of the LCD module.
Custom charactersThe character LCDs support ASCII characters that serve as a standard set of characters. The patterns for the supported characters are already stored in the memory (CGROM) of the LCD module. For printing these standard characters, the controller simply needs to “pass” the associated data register value to the address counter of the LCD.
That data register value is, then, stored in the DDRAM and the address counter is updated (and increased or decreased depending on the direction of the text). When the LCD has to print a character, it reads the value from the DDRAM, compares it with CGROM, and prints the character by generating the stored pattern for that character.
Sometimes it’s necessary to print user-defined characters/icons on an LCD. For example, you may be using an LCD module in a communication device and need to print a custom character showing the status of the connectivity. A character LCD may be embedded in a battery-operated device and it may be necessary to display the level of charging by using a custom icon.
The LCD modules, apart from DDRAM, have the CGRAM to store user-defined characters. To generate a custom character/icon, it’s necessary for the controller needs to pass the entire character pattern to the LCD module. This character pattern is stored in the CGRAM of the LCD. A 16×2 LCD module typically has enough CGRAM to store a pattern for 8 characters/icons.
The pattern for custom characters is defined as a group of 7, 8, or 10 bytes, depending on the number of rows of pixels for each character on the LCD. Each byte represents a row of pixels that form the character. The bits of the byte represents the status of the pixels (i.e. whether the respective pixels will turn on or off).
For example, on a 16×2 LCD, each character is printed as 5×8 dots. Therefore, 8 bytes (for 8 rows of pixels) are used to represent a character and 5 LSBs of each byte are used to turn on or off the pixels.
CGRAMMost of the character LCD modules use an HD4478 controller. There can be a different LCD controller on an LCD module. To know what controller is used in an LCD module, simply refer to its data sheet.
Depending on the size of the character LCDs, they have different DDRAM and CGRAM. For example, a 16×2 LCD has 80 bytes of DDRAM and 64 bytes of CGRAM. As there are 8 rows of pixels for each character, the pattern for 8 characters of 5×8 dots can be stored on the CGRAM.
The CGRAM addresses start from 0x40. The first character is stored from address 0x40 to 0x47. This custom character can be printed at the current cursor position by sending the command ‘0’ to the LCD module. The second custom character is stored from the address 0x48 to 0x4F. It can be printed at the current cursor position by sending the command 1 to the LCD module.
Generating custom charactersIt’s fairly easy to create a custom character. Simply determine the pixel map of the character and, then, determine the bytes that should be written to the CGRAM to generate that character/icon. For a 16×2 LCD, which has 5×8 dots characters, the top three MSB for each byte can be ignored. The top three MSBs can be set to 0 in each byte while other bits can be set to 0 or 1, according to the pixels that should turn off or on.
Generating custom charactersTo create custom characters, typically the LCD command must first be set and the CGRAM address needs to be passed. Next, the LCD command to write data to the CGRAM needs to be passed.
When using Arduino, it’s even simpler to create a custom character/icon. The LiquidCrystal library on the Arduino platform has a function createChar() that creates custom characters and icons on an LCD. This function takes the position of the custom character and an array of bytes as an argument. The generated custom character can be flashed on an LCD at the current cursor position by using the write() or print() function.
The createChar() mskethodThe createChar() function creates a custom character/icon for use on an LCD. Essentially, it writes a user-defined character pattern (a pixel map of the character) to a given CGRAM address.
The position of the character is specified as a number. For example, in the case of 16×2 LCD, 8 custom characters can be defined and their position can be 0 to 7.
The write() methodThe write() function writes a character on an LCD. The character is written (displayed) at the current cursor position and the cursor is moved right or left according to the direction of text on LCD.
If the data passed is a string (quoted in double or single quotes) of ASCII characters, it is written as such. If it’s a number, the character corresponding to that position in the CGRAM is written on the LCD.
The print() methodThe print() method is used to print text to an LCD. If a custom character has to be written on the LCD using the print() method, then the char() function (with the position of the custom character as the argument), must be passed as the argument of the print() function.
Components required1. Arduino UNO x12. A 16×2 character LCD x13. A 10K Pot x14. A 330-Ohms Resistor or any low-value resistor x15. Breadboard x16. Male-to-Male Jumper Wires or Connecting Wires
Circuit connectionsThe LCD module used in this project is JHD162A. This is a 16×2 LCD module with 5×8 character dots. The LCD module has a 16-pin interface. The LCD is interfaced withArduinoin a 4-bit mode.
The LCD module is connected with Arduino in 4-bit mode. The LCD is first initialized and the display is cleared to get rid of any garbage values in the DDRAM.
The patterns for 16 different custom characters are then generated by defining their pixel maps as arrays. Eight of these custom characters can be displayed on the LCD at one time. This is because 64 bytes of the CGRAM of the 16×2 LCD can store a pattern for only 8 characters at any time.
The 8 custom characters are generated by defining their character maps. The cursor position on the LCD is set from column 0 of line 0 to column 7 of line 0, and each character is displayed one by one. Then, the next 8 custom characters are generated and they’re displayed on line 0 of the LCD at the cursor positions from columns 0 to 7.
In the loop() function, the first 8 custom characters are generated using the customChar() method. The cursor position is set by using the setCursor() method. Each character is printed on the LCD by using the print() method at the cursor positions of column 0 to 7 of line 0, one after the other.
After the printing of the 8 characters, a two-second delay is provided using the delay() function. Then, the LCD is cleared by using the clear() method.