raspberry pi lcd display tutorial supplier

After I posted my Raspberry Pi server room rack temperature monitor project, I received many questions on how to integrate LCD displays with the Pi. This video is the first in a series of tutorials:

R is the resistor value in ohms and Vdd is the supply voltage. VLED and ILED are the typical LED voltage and current respectively as specified in the LCD display datasheet. Even if you display supports 5 V you might want to add a resistor or variable resistor to control the brightness. The same holds true for the contrast pin. I normally use variable resistors for both (see below).

I’ll demonstrate 2 different Python modules for controlling the LCD display. The first is a modified version of lcd.py by Raspberry Pi Spy which can be downloaded below.

You can use any GPIO pins for the LCD RS, E, & D1 – D4. The GPIO to LCD pin mappings are specified in the LCD.py file. If you change from the default below then you have to update the file with your new selections.

Here is some sample code (updated 4/23/16) to demonstrate the Adafruit library. As with the LCD.py module, you can use any GPIO pins. You specify the GPIO to LCD pin mappings when you instantiate the Adafruit_CharLCD class. Please note that super-user privileges are no longer required for GPIO access with the latest version of Raspbian

A potentiometer can be added to the LCD display C pin to control the contrast. The pin is connected to the wiper of the pot which is usually the middle pin. One of the outside pins is connected to ground and the other to Vcc. It doesn’t matter which outside pin goes to Vcc or ground because the pot is acting as a voltage divider either way. As the dial is turned the wiper’s pin voltage will vary from 0 to 5 V and this will cause the contrast to change. 10 KΩ is a good value for the pot. This same wiring will also work to control the LCD display brightness. Instead of of the contrast pin, the wiper would be connected to the LED back light anode. Most LCD display back lights will tolerate 5 V but please double check so you don’t damage the LED. You can alter the 0 – 5 V range by adding a resistor in series with one of the outside pins. This can help fine tune the amount of range provided by the pot. You can use a multimeter to measure the voltage on the wiper and determine how different resistors affect the range. Here is a simple schematic:

The Adafruit IP clock example from the video is no longer compatible with the latest version of the Adafruit LCD_Char library. Here is an updated version of the IP clock program. Please note that sudo is no longer necessary to run the program with the latest version of Raspbian, but you still need the shebang line and chmod +x to give the file executable permissions, if you run it from the command line.

The Adafruit_Python_CharLCD library has been deprecated since this tutorial was released in 2014. Therefore, I’m including an example using the newer Adafruit_CircuitPython_CharLCD library which can run on both the Raspberry Pi and other CircuitPython compatible boards. I have several CircuitPython tutorials. The library can easily be installed using pip:

It is possible to connect multiple LCD displays to a Raspberry Pi. Normally I’d recommend using an I²C display as discussed in my Using an I²C LCD Display with a Raspberry Pi tutorial because the wiring is less complicated. However, LCD displays can be daisy chained in 4 bit mode. The second display is connected to the existing GPIO pins for RS and D1 – D4, but each display must have a unique GPIO pin for Enable.

If your display is equipped with an IC2 module, it’s not that difficult to connect an LCD display to a Raspberry Pi. Learn with this tutorial how to connect and to program an 1602 LCD with a Raspberry Pi.

There are many types of LCD displays. In this tutorial we are using the popular and affordable 1602 LCD. The LCD has an IC2 module soldered on it (see the pictures below). If your LCD is of the same type, but has a different size, it won’t be a problem to continue with this tutorial. You’ll just have to correct some parameters in the Python script. But if it is from a different type or it has no I2C module, you better look for another tutorial.Prepare the hardware

– First, you need to have a Raspberry Pi running on the latest version of Raspberry Pi OS. This version includes “Thonny”. We’ll use this user-friendly IDE to write our Python code. If you’re not familiar with Python or with Thonny or GPIO-pins, I suggest to have a look at our tutorials “How to write your first Python program on the Raspberry Pi” and/or “How to use the Raspberry Pi GPIO pins” to have a quick introduction.

In this tutorial we are using the popular and quite basic 16×2 or 1602 LCD. It can display 16 characters per line on 2 lines. Each character is made from a matrix with 5×7 dots. It is equipped with a backlight for easy reading. Besides sending text, thanks to specific commands, we can give instructions to the display, as to switch on/off the backlight for example.

The display we use in this tutorial is equipped with a I2C-module (black part on the picture below). I2C is a communication protocol which allows an easier connection between the display and the Raspberry Pi. Indeed, instead of having to wire all the pins on the top of the screen, we only have to connect the display with 4 wires to our Raspberry Pi.

Each I2C device has its own I2C address. Often this address is hard-wired in the device and will vary from manufacturer to manufacturer. If you don’t know the address of your I2C device, connect the device to your Raspberry Pi (see the next step). Then, open a terminal window and enter following command :

If you bought one of our kits, the hexadecimal address of the LCD is ‘0x27’. We will need the I2C address from the display to insert it in our Python code.

Be careful ! Before starting to connect wires on the GPIO pins of your Raspberry Pi, make sure you properly shut down the Pi and removed the power cable from the board!

To avoid extensive and complicated code writing, libraries are often used. For our LCD, we will also be using a library. We found the most appropriate library at GitHub from Dave Hylands . As these files from this quite specific library don’t come automatically with Python, we have to install them ourselves.

So, before writing the code, we’ll have to upload the files to our Raspberry Pi. You can download a ZIP-folder containing the 2 files to be installed here.

Download and unzip the files. If you did this operation on your computer, upload the files to your Raspberry Pi. And if you don’t know how to do that, have a look at our tutorial ‘How to transfer files between Raspberry Pi and PC‘. Make sure you upload them in the same folder as the new file we will create for our main code. And don’t change the filenames of the library of course.

And before running the script, it’s important to adjust the contrast of your LCD. If the contrast isn’t adjusted well, it’s possible you don’t see appearing anything. You can adjust it by turning with a small screwdriver at the blue potentiometer at the back of your LCD (see the pictures here above). Make sure the backlight of the display is on to see the result. If the LCD’s contrast is adjusted right, you can just see the darker rectangles for the characters appear.

Besides the commands we used in the last lines of our script, there are more possibilities to communicate with the LCD. If you want to learn more about, have a look at this Github webpage.

Connecting an LCD to your Raspberry Pi will spice up almost any project, but what if your pins are tied up with connections to other modules? No problem, just connect your LCD with I2C, it only uses two pins (well, four if you count the ground and power).

In this tutorial, I’ll show you everything you need to set up an LCD using I2C, but if you want to learn more about I2C and the details of how it works, check out our article Basics of the I2C Communication Protocol.

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

There are a couple ways to use I2C to connect an LCD to the Raspberry Pi. The simplest is to get an LCD with an I2C backpack. But the hardcore DIY way is to use a standard HD44780 LCD and connect it to the Pi via a chip called the PCF8574.

The PCF8574 converts the I2C signal sent from the Pi into a parallel signal that can be used by the LCD. Most I2C LCDs use the PCF8574 anyway. I’ll explain how to connect it both ways in a minute.

I’ll also show you how to program the LCD using Python, and provide examples for how to print and position the text, clear the screen, scroll text, print data from a sensor, print the date and time, and print the IP address of your Pi.

Connecting an LCD with an I2C backpack is pretty self-explanatory. Connect the SDA pin on the Pi to the SDA pin on the LCD, and the SCL pin on the Pi to the SCL pin on the LCD. The ground and Vcc pins will also need to be connected. Most LCDs can operate with 3.3V, but they’re meant to be run on 5V, so connect it to the 5V pin of the Pi if possible.

If you have an LCD without I2C and have a PCF8574 chip lying around, you can use it to connect your LCD with a little extra wiring. The PCF8574 is an 8 bit I/O expander which converts a parallel signal into I2C and vice-versa. The Raspberry Pi sends data to the PCF8574 via I2C. The PCF8574 then converts the I2C signal into a 4 bit parallel signal, which is relayed to the LCD.

Before we get into the programming, we need to make sure the I2C module is enabled on the Pi and install a couple tools that will make it easier to use I2C.

Now we need to install a program called I2C-tools, which will tell us the I2C address of the LCD when it’s connected to the Pi. So at the command prompt, enter sudo apt-get install i2c-tools.

Next we need to install SMBUS, which gives the Python library we’re going to use access to the I2C bus on the Pi. At the command prompt, enter sudo apt-get install python-smbus.

Now reboot the Pi and log in again. With your LCD connected, enter i2cdetect -y 1 at the command prompt. This will show you a table of addresses for each I2C device connected to your Pi:

We’ll be using Python to program the LCD, so if this is your first time writing/running a Python program, you may want to check out How to Write and Run a Python Program on the Raspberry Pi before proceeding.

There are a couple things you may need to change in the code above, depending on your set up. On line 19 there is a function that defines the port for the I2C bus (I2CBUS = 0). Older Raspberry Pi’s used port 0, but newer models use port 1. So depending on which RPi model you have, you might need to change this from 0 to 1.

The function mylcd.lcd_display_string() prints text to the screen and also lets you chose where to position it. The function is used as mylcd.lcd_display_string("TEXT TO PRINT", ROW, COLUMN). For example, the following code prints “Hello World!” to row 2, column 3:

On a 16×2 LCD, the rows are numbered 1 – 2, while the columns are numbered 0 – 15. So to print “Hello World!” at the first column of the top row, you would use mylcd.lcd_display_string("Hello World!", 1, 0).

You can create any pattern you want and print it to the display as a custom character. Each character is an array of 5 x 8 pixels. Up to 8 custom characters can be defined and stored in the LCD’s memory. This custom character generator will help you create the bit array needed to define the characters in the LCD memory.

The code below will display data from a DHT11 temperature and humidity sensor. Follow this tutorial for instructions on how to set up the DHT11 on the Raspberry Pi. The DHT11 signal pin is connected to BCM pin 4 (physical pin 7 of the RPi).

By inserting the variable from your sensor into the mylcd.lcd_display_string() function (line 22 in the code above) you can print the sensor data just like any other text string.

These programs are just basic examples of ways you can control text on your LCD. Try changing things around and combining the code to get some interesting effects. For example, you can make some fun animations by scrolling with custom characters. Don’t have enough screen space to output all of your sensor data? Just print and clear each reading for a couple seconds in a loop.

Thanks for bringing this to my attention. It appears that the upgrade package overwrites the FBTFT drivers, in particular, the Raspberry Pi bootloader. This seems to solve the problem:

I just tested this, and it looks like the difference is how SPI is enabled. In the RPi 2 it’s enabled in raspi-config, not commented out in the blacklist file. I just updated the post so it should work now!

Looks like the only difference is in how SPI is enabled. In the new release of Raspbian, SPI is enabled in the raspi-config menu under advanced settings. In older versions of Raspbian, it is enabled by commenting out the line in the blacklist file

dwc_otg.lpm_enable=0 console=ttyAMA0,115200 console=tty1 root=/dev/mmcblk0p6 rootfstype=ext4 elevator=deadline rootwait fbtft_device.custom fbtft_device.name=waveshare32b fbtft_device.gpios=dc:22,reset:27 fbtft_device.bgr=1 fbtft_device.speed=48000000 fbcon=map:10 fbcon=font:ProFont6x11 logo.nologo dma.dmachans=0x7f35 console=tty1 consoleblank=0 fbtft_device.fps=50 fbtft_device.rotate=0

Unfortunately, their “driver” is an SD card image containing a complete installation of Raspbian which has been preconfigured to use their display. Which is fine if you’re setting up a brand new system that doesn’t need to be a specific distro, but if you’re trying to add the display to an existing Raspberry Pi, already configured the way you want it, with software installed and data present, or if you want to use a specific distro such as Octopi, then it’s not terribly helpful.

Hello..I tired to interface this lcd “https://www.crazypi.com/raspberry-pi-products/Raspberry-Pi-Accessories/32-TOUCH-DISPLAY-RASPBERRY-PI” to my Raspberry pi model B+.I got a DVD containing image for LCD in the package.I burned it to the SD card and plugged in the display.But my lcd is completly blank.But green inidcation led (ACT LED) in board is blinking.Why my LCD is Blank ?

My Touchscreen is now working fine.The problem was for the ribbon cable on the back side of LCD.It was not connected properly.I just tighted the cable and it worked fine.Hope it will be useful tip.

Thank you for this great tutorial. I looked everywhere for this information. I have an eleduino 3.5 version A. I was able to get it working on my Pi 2 by following your tutorial and using flexfb as the screen type. I got the other settings from the image that came with the product. I did find that the ts_calibrate didn’t recognize the screen so I installed xinput-calibrator and it worked fine.

Just got my Pi2 running Wheezy, working with the Eleduino 3.5 LCD without running the OEMs image… kinda. I didn’t want to rebuild the application environment again, so was avoiding flashing the SD.

I tried the steps in this tutorial. It’s very clear and easy to follow, thank you. But it didn’t work for me, I tried setting my device to flexfb. Only got white screen.

Unzipped it and looked around. From a shell script inside i kinda figured out what it was doing. I didn’t like what I saw, so I manually made changes omitting the parts I didn’t like (it rm -r my /lib/modules directory… omitted that part) and copied 2 files and 1 directory from the OEMs archive to the file system of my Pi2.

[ 0.000000] Kernel command line: dma.dmachans=0x7f35 bcm2708_fb.fbwidth=656 bcm2708_fb.fbheight=416 bcm2709.boardrev=0xa21041 bcm2709.serial=0x631a4eae smsc95xx.macaddr=B8:27:EB:1A:4E:AE bcm2708_fb.fbswap=1 bcm2709.disk_led_gpio=47 bcm2709.disk_led_active_low=0 sdhci-bcm2708.emmc_clock_freq=250000000 vc_mem.mem_base=0x3dc00000 vc_mem.mem_size=0x3f000000 dwc_otg.lpm_enable=0 console=ttyAMA0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline rootwait fbtft_device.custom fbtft_device.name=flexfb fbtft_device.gpios=dc:22,reset:27 fbtft_device.bgr=1 fbtft_device.speed=48000000 fbcon=map:10 fbcon=font:ProFont6x11 logo.nologo dma.dmachans=0x7f35 console=tty1 consoleblank=0 fbtft_device.fps=50 fbtft_device.rotate=0

thank you for your great tutorial, it got me on the right way. unfortunataly i only see some boot messages on the lcd and then it turns black. maybe you could give me a hint on how to get it working entirely.

i have a watterott display (https://github.com/watterott/RPi-Display) and changed the device-name to “rpi-display”. i use a rsapberrypi 2 and hae the latest raspian image installed.

I too have a raspberry pi 2, and a waveshare spotpear 3.2 RPi lcd (v3) and I just can’t get it to work! I suspect I have a faulty LCD, but thought I’ll try this forum for help before I sent it back.

Soon as the pi is powered, the LCD lights up all white, with a few vertical pixels coloured at one of the edges, and nothing else. I don’t think that should happen – not at least before the BOIS has started up.

Anyway, point 1, says to change to dev/fb1 – I don’t have fb1. Only fb0 appears to be there. is that a clue what could be wrong? I have enabled SPI (is there a command to tell if its enabled?) I have also ran spidev to troubleshot (though I haven’t a clue what I means)

Any ideas what going wrong? I am using the latest “2015-02-16-raspbian-wheezy_zip”. Enabled SPI. done all the steps. Even changed mmcblk0p2 to mmcblk0p6 as suggested by Dabomber60 (but that freezes for me)

[ 0.000000] Linux version 3.18.5-v7+ (pi@raspi2) (gcc version 4.8.3 20140106 (prerelease) (crosstool-NG linaro-1.13.1-4.8-2014.01 – Linaro GCC 2013.11) ) #1 SMP PREEMPT Fri Feb 6 23:06:57 CET 2015

It seems all appears to be working – just the LCD is still all white with a single line of coloured pixels on edge) and nothing else. Is there a way to output, like jeff G script, of touch points?

I had the same one, I finally found a driver for it here: http://www.waveshare.net/wiki/3.2inch_RPi_LCD_(B) you will need to translate the page, but unpack the driver then run sudo ./LCD-show/LCD32-show. It should reboot and all will be good with the screen :)

Can anyone let me know if the default OS image sent with the screen works with pi2 or just Pi B/B+ as i think my screen maybe broken but can’t confirm it yet as i have not had it working at all

My system: Raspberry Pi 2 Model B with Raspian Wheezy from Febuary 2015. LCD display of Sainsmart 3.2 http://www.conrad.de/ce/de/product/1283498/Raspberry-Pi-Display-Modul-Touch-Display-81-cm-32/?ref=home&rt=home&rb=1

dwc_otg.lpm_enable=0 console=ttyAMA0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 cgroup_enable=memory elevator=deadline rootwait fbtft_device.custom fbtft_device.name=sainsmart32_spi fbtft_device.gpios=dc:24,reset:25 fbtft_device.bgr=1 fbtft_device.speed=48000000 fbcon=map:10 fbcon=font:ProFont6x11 logo.nologo dma.dmachans=0x7f35 console=tty1 consoleblank=0 fbtft_device.fps=50 fbtft_device.rotate=90

sainsmart32_spi width=320 height=240 buswidth=8 init=-1,0xCB,0x39,0x2C,0x00,0x34,0x02,-1,0xCF,0x00,0XC1,0X30,-1,0xE8,0x85,0x00,0x78,-1,0xEA,0x00,0x00,-1,0xED,0x64,0x03,0X12,0X81,-1,0xF7,0x20,-1,0xC0,0x23,-1,0xC1,0x10,-1,0xC5,0x3e,0x28,-1,0xC7,0x86,-1,0×36,0x28,-1,0x3A,0x55,-1,0xB1,0x00,0x18,-1,0xB6,0x08,0x82,0x27,-1,0xF2,0x00,-1,0×26,0x01,-1,0xE0,0x0F,0x31,0x2B,0x0C,0x0E,0x08,0x4E,0xF1,0x37,0x07,0x10,0x03,0x0E,0x09,0x00,-1,0XE1,0x00,0x0E,0x14,0x03,0x11,0x07,0x31,0xC1,0x48,0x08,0x0F,0x0C,0x31,0x36,0x0F,-1,0×11,-2,120,-1,0×29,-1,0x2c,-3

ads7846_device model=7846 cs=1 gpio_pendown=23 speed=2000000 keep_vref_on=1 swap_xy=1 pressure_max=255 x_plate_ohms=60 x_min=300 x_max=3800 y_min=700 y_max=3400

The LCD display shows the raspberry correctly. However, the touch screen input does not work. The mouse pointer can I move correctly with your finger, but I can not select things (function of the left mouse button).

Thank you so much for this great tutorial. I have my WaveShare SpotPear 3.2″ V4 working fine on my Raspberry Pi 2. If you are having problems with this specific hardware, skip step 5.

Do not follow this article when you don’t know what kind of LCD module. In my case, I follow all of this and my raspberry pi cannot boot anymore. I will try to recover, but I think I should format my SD card and reinstall OS.

Expecting this would builtin driver module within kernel and help with avoiding mistakenly overwriting anything. But with this is cause LCD screen to go blank white and no boot activity. Also noticed on HDMI it get stuck on Initial rainbow screen and stuck on that.

Also can you someone explain what exactly happen when do rpi-update? Want to understand what this step actualy doing and help me to debug any such situation and able to help others.

Does anyone tried splash boot screen with waveshare v4 LCD and Rpi2? I tried to follow some example from https://github.com/notro/fbtft/wiki/Bootsplash but no success.

Great tutorial thanks; got an X session working great 1st time. Has anybody managed to get Kodi/XMBC working on the LCD either Kodi standalone, Raspbmc or Xbian?

in the video you say to change the existing line to “snd-bcm2836” for the rasppi2 which isn’t listed in the written part of the instructions (part 4).. this should be added (I believe it caused me to have to re-image the OS again, the Pi wouldn’t boot to anything just using the written steps)

fbtft_device name=waveshare32b gpios=dc:22,reset:27 speed=48000000 width=320 height=240 buswidth=8 init=-1,0xCB,0x39,0x2C,0x00,0x34,0x02,-1,0xCF,0x00,0XC1,0X30,-1,0xE8,0x85,0x00,0x78,-1,0xEA,0x00,0x00,-1,0xED,0x64,0x03,0X12,0X81,-1,0xF7,0x20,-1,0xC0,0x23,-1,0xC1,0x10,-1,0xC5,0x3e,0x28,-1,0xC7,0x86,-1,0×36,0x28,-1,0x3A,0x55,-1,0xB1,0x00,0x18,-1,0xB6,0x08,0x82,0x27,-1,0xF2,0x00,-1,0×26,0x01,-1,0xE0,0x0F,0x31,0x2B,0x0C,0x0E,0x08,0x4E,0xF1,0x37,0x07,0x10,0x03,0x0E,0x09,0x00,-1,0XE1,0x00,0x0E,0x14,0x03,0x11,0x07,0x31,0xC1,0x48,0x08,0x0F,0x0C,0x31,0x36,0x0F,-1,0×11,-2,120,-1,0×29,-1,0x2c,-3

ads7846_device model=7846 cs=1 gpio_pendown=17 speed=1000000 keep_vref_on=1 swap_xy=0 pressure_max=255 x_plate_ohms=60 x_min=200 x_max=3900 y_min=200 y_max=3900

After following this tut to the letter on a brand new image of Raspian, I find that the touch driver does not function. Anyone experience the same? Basically all I did was image a current copy of rasping, did a apt-get upgrade, and then did this tutorial. Then the touch driver does not work, meaning the pointer does not respond.

The reason I did this was because on a production version of my system I added the 3.2 screen and it worked great except for the x-axis. So I wanted to see if there was something in my system that was interfering or if this is another error. Now with a raw rasping the driver does not work at all. I wonder if the touch pin has changed since the kernel is using BCM pins instead of GPIO pin numbers?

I have exactly the same problem. I also installed a new version of Raspbian, and the LCD part works fine (except all the windows are way too large), but the touch part doesn’t work at all… I’m using Waveshare Spotpear 3.2″ V4.

I remember that I plugged in the screen wrongly one time, before configuring any of the GPIO pins. Can this have damaged the screen? Still it’s weird that the display part works well and the touch part not at all.

I do not think that has anything to do with it. Other than power pins, the rest are communication. If it still works then you are good. No, there is something else. I do suspect it us related to the BCM pin numbering. The real question is… Why isnt the eeveloper responding? I have since abandoned this TFT because of his lack of response.

Touch actually goes through one of the SPI pins I think. Either the driver is toast with the required kernel update or the driver is using the wrong pin. It is very likely the this works well with previous raspian versions, but not with the new B+ and with the new kernel.

I am trying to use the sainsmart 2.8″ lcd sold through microcenter, using the sainsmart32_spi … seems to have the same pinouts, should I be able to get this to work? I am stuck at the white out screen on the lcd, doesn’t seem to recognize the module either.

Unfortunately I’ve tried that ( a few times actually) but the file still doesn’t exist. Thanks very much for the assistance anyway. I must be doing something wrong. My Raspian came from a Noobs installation, I’m wondering if I should try installing the OS from somewhere else. My LCD screen didn’t come with a CD or any docs so I’m completely in the dark here.

I have just found a way to get this file on my system! Apparently its part of the fbturbo installation. I found it here http://www.raspberrypi.org/forums/viewtopic.php?f=63&t=45746&start=75 (under experimental enhanced x driver (rpifb).. Sorry if this is obvious to everyone but I am SUCH a noob at this!!

Ok, what am I doing wrong. I am using a fresh install of the newest raspbian, on a Pi 2. After doing the first two steps and rebooting I get the rainbow screen, then the boot up process, and then my screen just goes black with a flashing cursor in the top left. I am not able to enter any commands or anything…like the pi is halting just after boot up. Any thoughts/suggestions would be greatly appreciated. Thanks.

Well figured out that step 1 was causing my problems. I’m guessing it is shutting off my hdmi feed and trying to switch it over to the SPI, am I guessing right? If so, not sure how I’m suppose to complete the rest of the steps if my hdmi output gets turned off before the LCD is actually set up to work…that sounds kind of smartass-like, which is not my intention, just looking for some clarification on what is going on in that first step as I am fairly new to this stuff. Thanks.

Anyway, I was able to do the rest of the steps with no problem. LCD didn’t work, but I am using a Waveshare 3.5, which doesn’t look to be supported yet. Mostly I am trying to play around and see if I can get it working somehow. Anyone found a way to do this yet?

Here is a link to an updated image from waveshare. Upon install it got the display up and running, but I still do not have touch functionality. I’ve been playing around with it, but it has been to no avail…hopefully someone better at this stuff from me can get the touch working.

I am having an issue with getting the GUI back. Every time I use startx my pi just sits there for about two minutes saying “No protocol specified”, and then it just gives up. I went through this tutorial about four times now and am not certain why it is doing this. I have the exact same LCD as is in the tutotial (WaveShare 3.2b). any help would be great.

Hi I am making a project for school,using the raspberry pi b+ and waveshare spotpare 3.2b. Everything works except the touch input doesn’t work. Any help would be appreciated very much.

Thanks for the tutorial. It works, but I get the boot/command line stuff on the HDMI monitor and the LCD only comes on when I do startx. Is there a way to get everything to appear on the LCD screen?

I am trying to get this same screen to work with the image of RetroPie 2.6 and it won’t work. I have followed all the steps and nothing, please help I an kinda a noob.

I have a Tontec 7 inch touchscreen with a Raspberry Pi 2 B. After following the instructions the touch screen is functioning but not properly… The only are that works is the upper left (and only a small area of that). I tried changing the width and height in the modules but it didnt change anything. Also the xy seems to be reversed, I changed the swap_xy to 1 but again no change on the screen.

Now the OS freezes at the emulation station loading screen, and if I connect my lcd it gives me a lot of error messages which I can only see on the 3.2 inch screen.

hi i have the same screen with a raspberry pi 2 im trying to run retro pie but it wont show ..however it shows all the commands …but i cant get it to show the gui …if u guys can make an image or something please i have been in this pain for two weeks already thank you

well ,,i follow all instructions and still kernel panic ,,,,may i request from mr. Circuitbasics@Gmail.Com that have a contact with manufacture and just ask for 2-3 links for image files for different versions of pi till all this f discussions are finished,,i cant understand 10 guys said we run it and 40 guys said kernel panic ,,as an expert i did 50 times imaging and follow all changes fro this forum and other forums and still cant run it ,,,so sth is wrong …..just asking the manufacture for simple f image ,,that`s it ,,,,simpleeeeeeeeeeeeeeeee

well i did it at last on pi 2,,after reading 100 pages and reimaging 50 times ,,i finally find the solution ,,,,there is a simple line forgotten to be attached in setup instruction,,,well i give u clue for prodigies ,,there is a step left between step 3 and 4,,,,and a simple change in step 5 according to your pi version ,,,that`s it ,,nothing else,,,,

Damn.. I thought I was kickin ass haha. I am using the SainSmart 3.2″.. the backlight is lit up and the pi was booting and everything just fine but on the final reboot it gets hung and says “nonblocking pool is initialized” ?? No idea what that means. But it’s def just frozen at this point.. on my main screen, and just the backlight is on the SainSmart.

This was an excellent tutorial. I have gotten an output to the screen, but no touchscreen usage . I have the Waveshare SpotPear 3.2 Inch LCD V4 screen, but using Raspberry PI 2 with wheezy. Any ideas?

Thanks a lot for this article. Very clear and easy . I am new in pi’s world and my 3.2″ screen is working fine. I rotate 90 º and works. I can use mouse and so on.Not problems.

I filed the steps to calibrate the screen but it did not work.I think because it did not find the TFT pin, because I think the touch problem is the assigned pin to control it changed.

I actually used the driver from here http://www.waveshare.com/wiki/3.2inch_RPi_LCD_(B) , from a new wheezy build, did nothing except enable SPI in config, install driver, and change mmcblk0p2 to mmcblk0p6 in cmdline.txt and it all worked, no drama.

Hi I managed to set up my touch screen ok but I now have the issue that everything desktop fits fine but the windows I open are all huge and I can’t remember how to change the size and cannot see the option in desktop preferences any idea what I have to do and is it at all possible to install kodi to run through the raspbian is as this would be a lot my useful than having to keep swapping os on every boot up many thanks in advanced hope you can help me

Advice to all who have the drivers from the (touch)screen manufacturer and cannot obtain those otherwise: you can skip everything and go to the update steps skipping the kernel and kernel modules update (as mentioned by the author) so that you don’t override the preinstalled drivers. I have a Waveshare 3.5″ RPi v3 (not the 3.2″ supported by notro’s drivers) and actually managed without any problems to get notro’s drivers make it work. However I am still reading about the xinput and xinput-calibrator to figure out how to include it as a kernel module so that I can compile my own kernel and add it there.

i have raspberry pi 2 with 3.2 inch rpi lcd v4 waveshare spotpear.i have done as per your instructions.the display is working but touch screen not working.error shows waveshare32b module not found as well as touch screen module not found messages.

Hey! i did this and rotated it… It loads console perfectly, but when it goes into startx, i get a black background with only the wastebin/trashcan… how do i get the taskbar(or whatever that bar is called)? and the raspberry background?

Unfortunately I have lost the Touch facility on my Waveshare 3.5″ LCD Touchscreen? Can you offer any reasons as to why? I copied the Raspbian image to my Raspberry Pi from the Waveshare website first of all. The Touchscreen displays but is not reactive with any touch

I have purchased a raspberry pi B+ total kit and waveshare 3.2 TFT display online. In the package i have been given a pre-loaded NOOBS installed SD card. I did not even start anything yet. What should i do what r the things needed and how to connect the display i really want to know. I need help as i don’t know anything. Does the above solution help or will u suggest something………………..

Hi great article thanks. I am trying to get a waveshare 7 inch LCD with capacitive touch running it works with the suppled image but if you upgrade it breaks the capacitive touch. I have a sense-hat and GPS which require the latest kernel and RASPIAN image and the install program for the screen replaces the /lib/modules directory and the kernel with older ones. I need to be able to install the touch drivers into a new clean OS can anyone give me some pointers? Thanks

I have the WaveShare 3.5 (A) and cannot get it to work with the Kali Linux with TFT for Raspberry Pi. Have anybody gotten the A to work? (Not the B, theres instructions for the B already and dont work with A)

So I have the original image that came with my screen and it works fine with the LCD but my problem is that I want to use my LCD screen with other distros (at this time I am trying to use it with Kali Linux with TFT support by default https://www.offensive-security.com/kali-linux-vmware-arm-image-download/) What do I have to do to transfer the needed files from the original image that WORKS with the screen and use them with another image?

I originally bought this bundle http://www.amazon.com/gp/product/B013E0IJUK?psc=1&redirect=true&ref_=oh_aui_detailpage_o02_s00 with an RPi LCD V3 and no extra documentation on the specifics on the chipset. I tried with the bftft drivers but since I have no idea what to call this screen I just suppose it isn’t supported.

After 4 lost days I just decided to get another screen, a Waveshare 3.2 (just like the one on this tutorial), I’ll follow these steps and see if it work for me.

I am using the same LCD and followed your tutorial. Have your tested the guide lately? Are you certain that it works? I see the boot messages on console but I get white screen as GUI starts.

Oct 16 17:38:48 spare kernel: [ 12.544859] graphics fb1: fb_ili9340 frame buffer, 320×240, 150 KiB video memory, 4 KiB DMA buffer memory, fps=50, spi0.0 at 48 MHz

After I rebooted in step 3, my raspberry pi won’t boot up again. It goes thru the process of booting and the text scrolls down and every thing says “ok”. Then instead of going to GUI it just guys to a black screen on my monitor with a blinking underscore in the top left corner. Anyway to get around this? or should I start over with a fresh disk image??

That is what happens to mine also.. So long story short —> THIS SITE NEEDS TO BE UPDATED OR SHUT DOWN <— There are a hundred people on here that have all lost everything on the pi drive, and spent all day (or more) working thru this tutorial 4 or 5 (dozen) times and nothing. Just have to reinstall the os over again and again.

Please check out my answer, it may help you if it works. I’m not in that case but I’m assuming that the desktop environment simply doesn’t automatically start running anymore… This can be changed in the raspi-setup

Try typing ‘startx’ if you problem isn’t solved (assuming you’re using Raspbian and LXDE), it should start the desktop environment you’re used to see. What you’re seeing is the Command Line Input interface (CLI), the most basic way to interact with a computer. Hope I helped you a little

I have tried to set up waveshare 32b on my Pi B using the latest Raspian download. I learned a lot in the process using Windows Putty, Nano etc. I have repeated the setup process several times from scratch and included the corrections for possible overwriting. My Waveshare SpotPear 3.2 inch RPi LCD V4 just shows a white screen. Any suggestions?

There was no disk included. I asked for drivers and was given a download link to the image file. After down loading this I tried it and still got just a white screen. The HDMI monitor locks partway though the boot. I can still log in to pi using putty from my PC.

Hi, I am using raspberry pi 2 with raspbian jessie installed. I the waveshare spotpear 3.2 v4. The above instructions are not working. and after completing the steps there was no display from hdmi or lcd. One things to notify is.: the etc/modules files only had i2c-dev and not snd-bcm2835.

I am trying to get this to work with Retro Pie 3.3.1 and the Waveshare3.2″ v4 but I only get the terminal on the lcd and emulation station starts on hdmi. to get it working with retro pie i just replaced startx with emulationstation. how do i get this to work?

Sir, Your post has very useful to me. i am using Tinylcd. but i cant get display. i am performing all the steps in your post. i cant get touch controller information from the product website and also i am using RASPberryPi B+ model. could u please give me best solution to my work. Than you.

what if OS is not Raspbian, any other distro like Yocto project, etc.? Could you please specify process without “rpi-update” that makes driver installation process more generic, not dedicated to Raspbian.

I completed all steps except for the last one (I want it to boot to console). However, when I reboot, it never completes the boot process. I start in recovery mode and check the cmdline.txt file and it is exactly how it appears on this page. I copied the kernel info as well, but I am not sure if it correct as I cannot get to it to check. Any suggestions? I might just reinstall the OS and start over…

i installed android OS in raspberry pi 2. can i use same LCD touch screen set up for android installed raspberry pi 2 which you are used for raspbian.

Is it normal the white back light during the whole process of initializing (I suspect that during the transportation trere is a deffect)? The problem is that I missed the step #1 and I performed it at the end. Unfortunately I don’t have any monitor available right now – neither “normal”, neither LCD :))))). Is it possible turning back the system or the only option is reinstallation of the Raspbian?

I’m trying to use an original Raspberry Pi model B with a cheap 3.5 inch 320×480 LCD which allegedly was manufactured to work with the Pi and has the correct fittings to fit over the GPIO pins. The operating system is the latest, downloaded yesterday and installed with NOOBS. I can’t get past step 2 of this guidance. When I reboot after using raspi-config I can see text generated as the Pi boots, then the HDMI fed screen goes blank apart from a flashing cursor in the top left hand corner. The LCD just remains white with nothing else on it. I have missed out step 1 and rebooted after step 2 and the screen functions as I would expect. Does anyone have any ideas please?

Thanks for the great tutorial. I do have a question. Once you install the drivers for the lcd are you effectively disabiling the hdmi port or is it still available to use and will the pi function with both displays. I have a pi 3

once you install the drivers it replaces the kernel by disabling hdmi output and enables it for LCD. i don’t think we have a solution to get em both working at the same time. ( you are encouraged to search for it )

Thanks for the guide, have been doing this with my son but once we leave raspi config and reboot all we get is a black screen with a flashing white horizontal line (dash). Can you help? I have looked in the comments at the end of the article but no one else appears to have this issue.

I have a raspberry pi 2 with waveshare screenn 3.5 inches. Isn’t it the same instructions. But it isnt working, all i get is a white screen, and the red led on the pi is on. The green LED isnot working.

i am sorry, but i am a naive , and i have this question, can we upload any file into it for the display? like have a software in which if i tap it gives back a feedback to the code?

My Rpi3 gets “ERROR: could not insert ‘spi_bcm2708’: No such device” after I enable SPI in the raspi-config.My Rpi3 is freezing on the rainbow screen after I reboot at the end of step 3. I’ve tried adding boot_delay=1 to config.txt.

if any interested, now i have a raspian image working on raspberry 3 with Waveshare 3.5, also with sdr support for dongles and FreqShow working perfectly on touch

I’m a proper novice, have no coding experience. A these tutorials and walk throughs are invaluable. So thank you in advance for all the help and support.

I tried following your tutorial but I got stuck right at the first step… I enter sudo nano /usr/share/X11/xorg.conf.d/99-fbturbo.conf the whole screen is blank except for the command list at the bottom…

ads7846_device model=7846 cs=1 gpio_pendown=17 speed=1000000 keep_vref_on=1 swap_xy=0 pressure_max=255 x_plate_ohms=60 x_min=200 x_max=3900 y_min=200 y_max=3900

No matter what I do, I can’t get this to work. It works perfectly fine on my Pi2, but when I follow and use the guide on my Zero, I always end up with the activity LED blinking 8 times (corrupt SD/filesystem error).

I’d like to find the driver software for my 7″ LCD with touch (official Pi unit) so that I can use it in buildroot. I wanted to make sure this kernel is the one before I started digging further.

I started through your tutorial and completed step 3 and rebooted. After the Raspberry screen and some of the boot text on my HDMI monitor, I now have a black HDMI monitor and a white screen on my LCD. Does this mean that the bootloader was overwritten or something else is wrong? How am I supposed to enter in the proposed fixes to the bootloader, when I can’t get the RPi to boot? Do I have to interrupt the boot process at some point to reinstall the bootloader or what?

Its a script. Download and instead of running sudo ./LCD4-show run cat ./LCD4-show to simply display what it does without actually running it. The commands are fairly simple modifying a few files. I actually saved the LCD-show.tar.gz on my own server for faster future download but also for backup as it saved me tons of hours (if that’s a measuring unit for time :) )

I used this link though (smaller file ~ 50 KB, fast download) http://www.waveshare.com/w/upload/4/4b/LCD-show-161112.tar.gz and replaced LCD4-show with LCD32-show in the last line.

I’m using RasPi Zero with latest (as of last week) Jessie Raspbian. Did you run the script? If it didn’t work and you have modified other files in the process of making it work, I would recommend installing a fresh installed image on a new card and running the script. Can you suspect the screen being faulty or got “burned” in the process?

i bought a 3.5 inch tft lcd screen from banggood. and i have installed raspian jessie, the latest version, in my sd card. but when i power on my Pi, only a white backlit screen comes. there are no images or graphics whatsoever.

The owner of this article should including a WARNING in the header that if someone follows the steps, they will install a deprecated driver (which is only visible as tiny text on its gethub page here https://github.com/notro/rpi-firmware). This driver after install will break Raspberry Pi and the SD card will need to be reimaged, for some less experienced users, this could also mean lost work if they failed to backup their code or resources. On windows, it requires installing Linux reader software and it takes a long time to fix this f**kup which could easily have been avoided if the author had and sense of responsibility.

PLEASE DELETE this article. You have great power with this article showing up for so many people in their search results, and you display ZERO responsibility. This is terrible!

I have done every thing right but the only major problem is that the screen is still white and my raspberrypi freezes after a line of code when booting up and I cant get in with SSH

Will your system work with my SainSmart 2.8″ 2.8 inch TFT LCD 240×320 Arduino DUE MEGA2560 R3 Raspberry Pi ? I would like to know before not be able to back out. Thanks, Lee

I know I will end up regretting this, but how do I change fb0 to fb1? I’m on the screen that has all the info, but no way to change it. Am I looking for a file? I have had my screen for MONTHS and I can’t do anything with my pi or the screen. I am >< close to smashing both. COMPLETE WASTE OF MONEY so far!!

hello. I really appreciate your blog post. I have a raspberry pi 3 B. I have been unable to get my waveshare 3.2 screen to work.I am at a complete loss for what to do. I do step 2 I change fb0 to fb1 and then follow your directions I don’t get the prompt to reboot; however, I do it manually with sudo reboot. that works fine then I complete step three and that works just fine; however once I reboot from getting those drivers and when I attempt to reboot it is unsuccessful and then my whole raspberry pi will not restart. then when I power it back on it will just shut back off. I then have to redo noobs onto a new SD card I would GREATLY appreciate anyones help

I ‘m actually using a LCD Waveshare3.2” , I followed your steps to setup the lcd touchscreen for my rpi and it work but I have a problem with the resolution because if I open a repertory I do not see the whole contents on the screen .

hi! thank you for this post…. I was wondering if all the raspberry pi’s gpio are being held by this screen or do we have any of those availables for use??

it worked. but the resolution is for bigger screens. i got the menubar small, but the rest appears too big , and out of screen. the wastebasket icon is 1/6 of my 3.2″ screen. wich HAS the resolution capability too display the whole desktop. But i’m a PI newby and dunno how to adjust the screen resolution on this display. anybody?

I did a 5inch LCD for my raspberry pi. I dont use the touchscreen so i didnt have to install any drivers. It works out of the box but doesnt cover the whole screen unless you open the terminal and do:

HI I have my RPI running Pi Presents on a view sonic TD2230 Touchscreen. It all works fine, touching the click areas can navigate you thru my presentation, The problem arises when you use multitouch gestures like you would on a iPhone. Pinch or expand etc… and then all touch ability goes away. I can still control the presentation via a mouse, but I don’t get touch control back until I either relaunch Pi Presents, or if I unplug and plug the usb cable going to the touchscreen.

Much of this is outdated on Raspbian Stretch where device tree overlays (see https://www.raspberrypi.org/documentation/configuration/device-tree.md) provide for most of the configuration automatically.

In the case of the WaveShare driver, their setup script from their “LCD_show” repository will copy a device-tree overlay to /boot/overlays/ that provides most of the module config etc via boot-time device-tree patch.

After I did the step that “INSTALL THE FBTFT DRIVERS” and then reboot, my raspberry pi couldn’t boot successfully and the green light is always on, could you help me solve this problem? Thank you.

The most common controller of multi-line character displays is the HD44780. There are several Raspberry Pi LCD display sizes (8×2, 16×2, 20×4, etc.) that run with it. In this tutorial, I will show how to use a 16×2 character display and also run a test script.

A few words said in advance: In this tutorial, all pins are addressed directly, which occupies quite a few GPIOs. Another method is the connection via I2C.

The backlight can be adjusted by turning the potentiometer. Some displays cannot stand 5V for the backlight, so you should either look at the datasheet or at least always connect a 470Ω – 510Ω resistor.

Raspberry Pi is an ARM architecture processor based board designed for electronic engineers and hobbyists. The PI is one of most trusted project development platforms out there now. With higher processor speed and 1 GB RAM, the PI can be used for many high profile projects like Image processing and IoT.

For doing any of high profile projects, one need to understand the basic functions of PI. We will be covering all the basic functionalities of Raspberry Pi in these tutorials. In each tutorial we will discuss one of functions of PI. By the end of this Raspberry Pi Tutorial Series, you will be able to do high profile projects by yourself. Go through below tutorials:

In this tutorial, we will Control a 16x2 LCD Display using Raspberry Pi. We will connect the LCD to GPIO (General Purpose Input Output) pins of PI to display characters on it. We will write a program in PYTHON to send the appropriate commands to the LCD through GPIO and display the needed characters on its screen. This screen will come in handy to display sensor values, interrupt status and also for displaying time.

There are different types of LCDs in the market. Graphic LCD is more complex than 16x2 LCD. So here we are going for 16x2 LCD display, you can even use 16x1 LCD if you want. 16x2 LCD has 32 characters in total, 16 in 1st line and another 16 in 2nd line. JHD162 is 16x2 LCD Module characters LCD. We have already interfaced 16x2 LCD with 8051, AVR, Arduino etc. You can find all our 16x2 LCD related project by following this link.

There are 40 GPIO output pins in Raspberry Pi 2. But out of 40, only 26 GPIO pins (GPIO2 to GPIO27) can be programmed. Some of these pins perform some special functions. With special GPIO put aside, we have 17 GPIO remaining.

There are +5V (Pin 2 or 4) and +3.3V (Pin 1 or 17) power output pins on the board, these are for connecting other modules and sensors. We are going to power the 16*2 LCD through the +5V rail.We can send control signal of +3.3v to LCD but for working of LCD we need to power it by +5V. The LCD will not work with +3.3V.

Here we are using Raspberry Pi 2 Model B with Raspbian Jessie OS. All the basic Hardware and Software requirements are previously discussed, you can look it up in the Raspberry Pi Introduction, other than that we need:

As shown in the Circuit Diagram, we have Interfaced Raspberry Pi with LCD display by connecting 10 GPIO pins of PI to the 16*2 LCD’s Control and Data Transfer Pins. We have used GPIO Pin 21, 20, 16, 12, 25, 24, 23, and 18 as a BYTE and created ‘PORT’ function to send data to LCD. Here GPIO 21 is LSB (Least Significant Bit) and GPIO18 is MSB (Most Significant Bit).

16x2 LCD Module has 16 pins, which can be divided into five categories, Power Pins, contrast pin, Control Pins, Data pins and Backlight pins. Here is the brief description about them:

6. Once this E pin goes low, the LCD process the received data and shows the corresponding result. So this pin is set to high before sending data and pulled down to ground after sending data.

As said we are going to send the characters one after the other. The characters are given to LCD by ASCII codes (American standard Code for Information Interchange). The table of ASCII codes is shown below. For example, to show a character “@”, we need to send a hexadecimal code “40”. If we give value 0x73 to the LCD it will display “s”. Like this we are going to send the appropriate codes to the LCD to display the string “CIRCUITDIGEST”.

We are going to import GPIO file from library, below function enables us to program GPIO pins of PI. We are also renaming “GPIO” to “IO”, so in the program whenever we want to refer to GPIO pins we will use the word ‘IO’.

Sometimes, when the GPIO pins, which we are trying to use, might be doing some other functions. In that case, we will receive warnings while executing the program. Below command tells the PI to ignore the warnings and proceed with the program.

We can refer the GPIO pins of PI, either by pin number on board or by their function number. Like ‘PIN 29’ on the board is ‘GPIO5’. So we tell here either we are going to represent the pin here by ‘29’ or ‘5’.

Depending on your display stand, you might find that the LCD display defaults to being upside-down. You can fix this by rotating it with /boot/config.txt.

If some windows in X are cut off at the side/bottom of the screen, this is unfortunately a side-effect of developers assuming a minimum screen resolution of 1024x768 pixels.

At the moment you can’t use HDMI and the LCD together in the X desktop, but you can send the output of certain applications to one screen or the other.

You may need to increase the amount of memory allocated to the GPU to 128MB if the videos are 1080P. Adjust the gpu_mem value in config.txt for this. The Raspberry Pi headline figures are 1080P30 decode, so if you are using two 1080P clips it may not play correctly depending on the complexity of the videos.

we’ll discuss various commands we use with the Python Module to make 16×2 display work via the I2C port on Raspberry Pi. So, let’s start today’s discussion. so , you can python too from this pyhton tutorial.

You’ll have use this LCD module either wither Arduino and NodeMCU Boards, might also with others. But to interface this with Raspberry Pi requires Python modules and code.

This LCD has 13 pins out of which 7 pins are used for making communication with the microcontroller. But as this can reduce the availability of the pins on Raspberry Pi, ironically.

This is the test code for displaying text on display. With this, we have completed I2C LCD Raspberry Pi Tutorial. I hope you enjoyed it and if you find any of the issues, let me know in comment below.

In this tutorial, I will show you how to add an LCD hat to your Raspberry Pi. This is an alternative to connecting an LCD display to your Pi through its HDMI port.

I will feature 4D Systems 4DPi-32 LCD hat in this tutorial. The 4DPi-32 is the 3.2" version of their 4DPi line of products which also include sizes 3.5" and 2.4".  It"s a resistive touchscreen, which means you need to have a stylus for it. You can buy the 4DPi-32 here

My Raspberry Pi is running Raspbian Stretch (November 2017 release) so make sure you have the same version before you proceed with this tutorial. You can download the Raspbian Stretch from the official site.

Next, we need to adjust the console size of the Pi to fit into the 3.2" screen. Since the 4DPi-32 has a screen resolution of 320 x 240 pixels, we need to adjust the framebuffer to this size. In the same config.txt file, locate the following lines:

To fit the contents of the console to the screen, we must change the framebuffer width and height to (width = 2 * overscan). For example, for a 320 pixel width, the framebuffer width should be 320 - 32 = 288. In short, uncomment the framebuffer lines and replace the values with these:

While the Pi is still off, mount the LCD hat. Then turn on the Raspberry Pi. If everything"s done right, you should now see the Pi"s desktop environment on the LCD screen.

The 4DPi-32 is a resistive touchscreen which means it would not respond to your fingers. You can use a stylus or any pointy (not too sharp) object that is non-conductive (plastic) to navigate through the screen. But first, you need to calibrate the touchscreen. To do that, install the following packages:

Computer monitors are great for office work, gaming, and browsing, but these displays can be large and power consuming. One display found in both the commercial and hobby world is the HD44780 16 x 2 display, which can display two lines of alphanumeric characters. In this tutorial, we will learn how to connect one to a Raspberry Pi and code it using the Python programming language!

The HD44780 has a number of registers and commands that are used to control the display, but getting the display to work can be somewhat tricky, especially for inexperienced users. This is why most coders will turn to libraries. They include prewritten code that has been proven to work. In this tutorial, we will be relying on two libraries to control the LCD: RPLCD and RPi.GPIO. Before we can continue, we need to install the RPLCD library by using the following command in a terminal window:

First, we need to import the RPi.GPIO library as GPIO. This will allow us to use the GPIO library and refer to it as “GPIO”, which is easier than RPi.GPIO. The next library that we need to include is the RPLCD library, which allows us to use the LCD. Therefore, the first two lines of code in our Python program will be:

CharLCD is a Python library that lets users access Adafruit character LCDs from a Raspberry Pi. Next, we need to tell the RPLCD library what pins we have connected the LCD to. In the Scheme-It schematic above, we connected the LCD pins to the following GPIO (using the BOARD numbering scheme). The Pi has two numbering schemes; BOARD and BCM. The BOARD numbering scheme refers to the I/O header whereas the BCM scheme refers to the GPIO numbers from the Broadcom IC. It is often easier to use BOARD scheme as you can count the pins to determine which one you need to use whereas the BCM scheme requires you to first choose a GPIO and then determine its pin number (BOARD).

Now that we have configured the LCD, it’s time to do a few tasks with it! The first function that we should learn to use is “write_string()”, which is used to write text to the LCD. Try the following command:

Writing predefined strings is not entirely helpful, and displaying variables can be very beneficial. Luckily for us, Python allows typecasting, where one variable can be converted into another variable. The example below shows how we can display a counter, which displays an integer on the LCD, along with a simple “Count” message.

Next, we’ll learn how to clear the display. Displays like those based around the HD44780 are static, and they remember what you tell them to display. However, this also means that when you want to write new data, you may need to clear the entire display. Therefore, you can use this clear function to clear the display:

Sometimes printing text on the top left of the display may not be desirable. In this case, you will need to change the cursor’s position. To do this, we can set the cursor_pos variable to a specific value. The example below sets the cursor position to row 2 (x) and column 0 (y).

At the end of your program, you should include the function “lcd.close()”, as this will free up the GPIO for other programs that may need to use them.

The 3.5 inch LCD Display is directly pluggable into a Raspberry Pi and perfectly fits various Pi models from B+ to Raspberry Pi 3B+. It is a brilliant alternative for an HDMI monitor. When set up, it behaves as a human-machine interface enabling the user to prototype with the Raspberry Pi device anywhere at any time.