lcd display for raspberry pi free sample
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Rather than plug your Raspberry Pi into a TV, or connect via SSH (or remote desktop connections via VNC or RDP), you might have opted to purchase a Raspberry Pi touchscreen display.
Straightforward to set up, the touchscreen display has so many possibilities. But if you"ve left yours gathering dust in a drawer, there"s no way you"re going to experience the full benefits of such a useful piece of kit.
The alternative is to get it out of the drawer, hook your touchscreen display to your Raspberry Pi, and reformat the microSD card. It"s time to work on a new project -- one of these ideas should pique your interest.
Let"s start with perhaps the most obvious option. The official Raspberry Pi touchscreen display is seven inches diagonal, making it an ideal size for a photo frame. For the best results, you"ll need a wireless connection (Ethernet cables look unsightly on a mantelpiece) as well as a Raspberry Pi-compatible battery pack.
Several options are available to create a Raspberry Pi photo frame, mostly using Python code. You might opt to script your own, pulling images from a pre-populated directory. Alternatively, take a look at our guide to making your own photo frame with beautiful images and inspiring quotes. It pulls content from two Reddit channels -- images from /r/EarthPorn and quotes from /r/ShowerThoughts -- and mixes them together.
Rather than wait for the 24th century, why not bring the slick user interface found in Star Trek: The Next Generation to your Raspberry Pi today? While you won"t be able to drive a dilithium crystal powered warp drive with it, you can certainly control your smart home.
In the example above, Belkin WeMo switches and a Nest thermostat are manipulated via the Raspberry Pi, touchscreen display, and the InControlHA system with Wemo and Nest plugins. ST:TNG magic comes from an implementation of the Library Computer Access and Retrieval System (LCARS) seen in 1980s/1990s Star Trek. Coder Toby Kurien has developed an LCARS user interface for the Pi that has uses beyond home automation.
Building a carputer has long been the holy grail of technology DIYers, and the Raspberry Pi makes it far more achievable than ever before. But for the carputer to really take shape, it needs a display -- and what better than a touchscreen interface?
Ideal for entertainment, as a satnav, monitoring your car"s performance via the OBD-II interface, and even for reverse parking, a carputer can considerably improve your driving experience. Often, though, the focus is on entertainment.
https://www.anrdoezrs.net/links/7251228/type/dlg/sid/UUmuoUeUpU10530/https://www.youtube.com/supported_browsers?next_url=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3Djpt3PiDNdEk
Setting up a Raspberry Pi carputer also requires a user interface, suitable power supply, as well as working connections to any additional hardware you employ. (This might include a mobile dongle and GPS for satnav, for instance.)
Now here is a unique use for the Pi and its touchscreen display. A compact, bench-based tool for controlling hardware on your bench (or kitchen or desk), this is a build with several purposes. It"s designed to help you get your home automation projects off the ground, but also includes support for a webcam to help you record your progress.
The idea here is simple. With just a Raspberry Pi, a webcam, and a touchscreen display -- plus a thermal printer -- you can build a versatile photo booth!
Various projects of this kind have sprung up. While the versions displayed above uses a thermal printer outputting a low-res image, you might prefer to employ a standard color photo printer. The wait will be longer, but the results better!
How about a smart mirror for your Raspberry Pi touchscreen display project? This is basically a mirror that not only shows your reflection, but also useful information. For instance, latest news and weather updates.
Naturally, a larger display would deliver the best results, but if you"re looking to get started with a smart mirror project, or develop your own from scratch, a Raspberry Pi combined with a touchscreen display is an excellent place to start.
Many existing projects are underway, and we took the time to compile six of them into a single list for your perusal. Use this as inspiration, a starting point, or just use someone else"s code to build your own information-serving smart mirror.
Want to pump some banging "toons" out of your Raspberry Pi? We"ve looked at some internet radio projects in the past, but adding in a touchscreen display changes things considerably. For a start, it"s a lot easier to find the station you want to listen to!
This example uses a much smaller Adafruit touchscreen display for the Raspberry Pi. You can get suitable results from any compatible touchscreen, however.
Alternatively, you might prefer the option to integrate your Raspberry Pi with your home audio setup. The build outlined below uses RuneAudio, a Bluetooth speaker, and your preferred audio HAT or shield.
Requiring the ProtoCentral HealthyPi HAT (a HAT is an expansion board for the Raspberry Pi) and the Windows-only Atmel software, this project results in a portable device to measure yours (or a patient"s) health.
With probes and electrodes attached, you"ll be able to observe and record thanks to visualization software on the Pi. Whether this is a system that can be adopted by the medical profession remains to be seen. We suspect it could turn out to be very useful in developing nations, or in the heart of infectious outbreaks.
We were impressed by this project over at Hackster.io, but note that there are many alternatives. Often these rely on compact LCD displays rather than the touchscreen solution.
Many home automation systems have been developed for, or ported to, the Raspberry Pi -- enough for their own list. Not all of these feature a touchscreen display, however.
One that does is the Makezine project below, that hooks up a Raspberry Pi running OpenHAB, an open source home automation system that can interface with hundreds of smart home products. Our own guide shows how you can use it to control some smart lighting. OpenHAB comes with several user interfaces. However, if they"re not your cup of tea, an LCARS UI theme is available.
Another great build, and the one we"re finishing on, is a Raspberry Pi-powered tablet computer. The idea is simple: place the Pi, the touchscreen display, and a rechargeable battery pack into a suitable case (more than likely 3D printed). You might opt to change the operating system; Raspbian Jessie with PIXEL (nor the previous desktop) isn"t really suitable as a touch-friendly interface. Happily, there are versions of Android available for the Raspberry Pi.
This is one of those projects where the electronics and the UI are straightforward. It"s really the case that can pose problems, if you don"t own a 3D printer.
This is a new Pi Pico display from Waveshare with many more pixels. It is a 2inch LCD display module, designed for Raspberry Pi Pico, with an embedded ST7789VW driver, 65K RGB colours, 320x240 pixels and an SPI interface. A Pi Pico can be plugged into the rear of the screen for very easy connection without any soldering. It sports 4 simple button switches for user input. It is bright, colourful and easy to program. The makers supply an example program (see below), which includes the display driver, making it very easy to get started. The manufacturer"s wiki can be found at:
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.
This repository contains all the code for interfacing with a 16x2 character I2C liquid-crystal display (LCD). This accompanies my Youtube tutorial: Raspberry Pi - Mini LCD Display Tutorial.
During the installation, pay attention to any messages about python and python3 usage, as they inform which version you should use to interface with the LCD driver. For example:
It is possible to define in CG RAM memory up to 8 custom characters. These characters can be prompted on LCD the same way as any characters from the characters table. Codes for the custom characters are unique and as follows:
This is demo showcases how extended strings could be used. Extended strings can contain special placeholders of form {0xFF}, that is, a hex code of the symbol wrapped within curly brackets. Hex codes of various symbols can be found in the following characters table:
For example, the hex code of the symbol ö is 0xEF, and so this symbol could be printed on the second row of the display by using the {0xEF} placeholder, as follows:
If you want to combine placeholder to write a symbol {0xFF} with the native Python placeholder {0} for inserting dome data into text, escape the non-native placeholders. Here is an example:
This demo uses ping and nc (netcat) to monitor the network status of hosts and services, respectively. Hosts and services can be modified by editing their respective dictionaries:
This is a demo of a graphical progress bar created with custom characters. This bar could be used, for example, for showing the current level of battery charge.
This is a script that shows a famous quote, a currency conversion pair of your choice and the weather of a city. It also shows the last three characters from your ip address, the date in DDMM format and the hour in HH:MM format
exchangerate-api.com / free.currencyconverterapi.com: There are a lot of currency apis but these ones offer free currency exchange info. Both are used, one as main, the other as backup. Requires an API key to use.
In order to use the script, you need to get API key tokens for both exchange rate services and the weather api. Once you"ve done that, edit the script to put your tokens in the USER VARIABLES section.
A city/country string is also needed to show weather info for such city. Search for your city on openweathermap.org and take note of the City,country string and put it in the script.London,gb is given as an example.
Thank you for you interest in learning how to contribute to this repository. We welcome contributions from novices to experts alike, so do not be afraid to give it a try if you are new to git and GitHub. First, however, take a few minutes to read our CONTRIBUTING.md guide to learn how to open Issues and the various sorts of Pull Requests (PRs) that are currently accepted.
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It’s not only the devices that have experienced rapid development. The development boards used for them have started to become more and more commercial and accessible.
For this demo, we will use the ClimaCell Weather API as a weather data provider, as they have a large number of indicators, including air quality indicators, for us to use.
As soon as we have this API key, we can move to the hardware configuration and connect the LCD screen to our Raspberry Pi. You should turn the Raspberry Pi off while you make the wire connection.
This hardware connection will make the LCD screen be on full brightness and full contrast. The brightness level is not a problem, but contrast is because we won’t be able to see the characters on the screen.
At this point, we can turn on our Raspberry Pi and we should see the LCD screen alive. With the help of variable resistance we should be able to control the contrast.
As a programming language, we’ll use NodeJS to write the code. If you don’t already have NodeJS installed on your Raspberry then you can follow these simple instructions.
In a new folder, run the command npm init -y to set up a new npm package, followed by the command npm install lcd node-fetch to install these 2 necessary dependencies.lcd will be used to communicate with the LCD Screen
We said that we need an API key to communicate with the weather data provider. You place your secret API key directly in the main code, or you can create a config.json file in which you can place this key and any other code-related configuration you may have.
Writing on the screen is a piece of cake using the lcd module. This library acts as a layer of abstraction over how we communicate with the device. In this way we don’t need to micro-manage each command individually.
The keys cols and rows represent the number of columns and rows of our LCD display. 16x2 is the one I used in this example. If your LCD has just 8 columns and 1 row, then replace 16 and 2 with your values.
At this point, you can use this function and print something on your display. writeToLcd(0,0,"Hello World") should print the message Hello World on the first row starting from the first column.
ClimaCell provides a lot of weather data information, but also air quality and pollen, fire and other information. The data is vast, but keep in mind that your LCD screen only has 16 columns and 2 rows – that’s just 32 characters.
To find your city’s coordinates, you can use a free tool like latlong.net and then you can save them in config.json file along with your API key, or you can write them directly in the code.
The weather data is updated every 5 minutes. But because we have a limit of 100 API Calls / Hour imposed by ClimaCell, we can go even further and update the weather data each minute.
To print the time in the upper right corner, we must first calculate the starting column so that the text fits snugly. For this we can use the next formula total columns number minus text to display length
The LCD setting is asynchronous, so we must use the method lcd.on() provided by the related library, so we know when the LCD has been initialized and is ready to be used.
Another best practice in embedded systems is to close and free the resources that you use. That’s why we use the SIGNINT event to close the LCD screen when the program is stopped. Other events like this one include:SIGUSR1 and SIGUSR2 - to catch "kill pid” like nodemon restart
At this point you’re probably connected to your Raspberry Pi using SSH or directly with an HDMI cable and a monitor. No matter what, when you close your terminal the program will stop.
From this point you can customize your new device however you want. If you find this weather data important for you (or any other data from ClimaCell, like air pollution, pollen, fire index or road risk), you can create a custom case to put the Raspberry Pi and the LCD display in it. Then after you added a battery you can place the device in your house.
Raspberry Pi is like a personal computer, so you can do much more on it than you would normally do on a microcontroller like Arduino. Because of this, it"s easy to combine it with other devices you have in your house.
It’s not only the devices that have experienced rapid development. The development boards used for them have started to become more and more commercial and accessible.
For this demo, we will use the ClimaCell Weather API as a weather data provider, as they have a large number of indicators, including air quality indicators, for us to use.
As soon as we have this API key, we can move to the hardware configuration and connect the LCD screen to our Raspberry Pi. You should turn the Raspberry Pi off while you make the wire connection.
This hardware connection will make the LCD screen be on full brightness and full contrast. The brightness level is not a problem, but contrast is because we won’t be able to see the characters on the screen.
At this point, we can turn on our Raspberry Pi and we should see the LCD screen alive. With the help of variable resistance we should be able to control the contrast.
As a programming language, we’ll use NodeJS to write the code. If you don’t already have NodeJS installed on your Raspberry then you can follow these simple instructions.
In a new folder, run the command npm init -y to set up a new npm package, followed by the command npm install lcd node-fetch to install these 2 necessary dependencies.lcd will be used to communicate with the LCD Screen
We said that we need an API key to communicate with the weather data provider. You place your secret API key directly in the main code, or you can create a config.json file in which you can place this key and any other code-related configuration you may have.
Writing on the screen is a piece of cake using the lcd module. This library acts as a layer of abstraction over how we communicate with the device. In this way we don’t need to micro-manage each command individually.
The keys cols and rows represent the number of columns and rows of our LCD display. 16x2 is the one I used in this example. If your LCD has just 8 columns and 1 row, then replace 16 and 2 with your values.
At this point, you can use this function and print something on your display. writeToLcd(0,0,"Hello World") should print the message Hello World on the first row starting from the first column.
ClimaCell provides a lot of weather data information, but also air quality and pollen, fire and other information. The data is vast, but keep in mind that your LCD screen only has 16 columns and 2 rows – that’s just 32 characters.
To find your city’s coordinates, you can use a free tool like latlong.net and then you can save them in config.json file along with your API key, or you can write them directly in the code.
The weather data is updated every 5 minutes. But because we have a limit of 100 API Calls / Hour imposed by ClimaCell, we can go even further and update the weather data each minute.
To print the time in the upper right corner, we must first calculate the starting column so that the text fits snugly. For this we can use the next formula total columns number minus text to display length
The LCD setting is asynchronous, so we must use the method lcd.on() provided by the related library, so we know when the LCD has been initialized and is ready to be used.
Another best practice in embedded systems is to close and free the resources that you use. That’s why we use the SIGNINT event to close the LCD screen when the program is stopped. Other events like this one include:SIGUSR1 and SIGUSR2 - to catch "kill pid” like nodemon restart
At this point you’re probably connected to your Raspberry Pi using SSH or directly with an HDMI cable and a monitor. No matter what, when you close your terminal the program will stop.
From this point you can customize your new device however you want. If you find this weather data important for you (or any other data from ClimaCell, like air pollution, pollen, fire index or road risk), you can create a custom case to put the Raspberry Pi and the LCD display in it. Then after you added a battery you can place the device in your house.
Raspberry Pi is like a personal computer, so you can do much more on it than you would normally do on a microcontroller like Arduino. Because of this, it"s easy to combine it with other devices you have in your house.
Insert the TF Card to Raspberry Pi, connect the Raspberry Pi and LCD by HDMI cable; connect USB cable to one of the four USB ports of Raspberry Pi, and connect the other end of the USB cable to the USB port of the LCD; then supply power to Raspberry Pi; after that if the display and touch both are OK, it means drive successfully (please use the full 2A for power supply).
After execution, the driver will be installed. The system will automatically restart, and the display screen will rotate 90 degrees to display and touch normally.
This LCD display supports Raspbian, Ubuntu MATE, Snappy Ubuntu Core, OSMC, and Windows 10 IOT Core and so on. Please download your system image from raspberry Pi official website: https://www.raspberrypi.org/downloads/
The 7″ LCD display is an LCD display which connects to the Raspberry Pi through the DSI connector. It is capacitive touch LCD. It doesn’t need install driver, and you can plug and play. The Physical resolution of LCD display is 800*480.
The touch screen can be used as a mouse device. When we need to input text data to Raspberry Pi board, normally we have to connect a USB keyboard to Pi and this is really inconvenient.
The physical resolution is 800*480, but you can adjust the resolution form 800×480 to 1920×1080. Open micro SD card which you have installed IMG system and then open “/boot/config.txt” via Notepad++, and find the following lines:
LCD displays have an optimum viewing angle, and depending on how the screen is mounted it may be necessary to change the orientation of the display to give the best results. By default, the Raspberry Pi display and Raspberry Pi are set up to work best when viewed from slightly above, for example on a desktop. If viewing from below, you can physically rotate the display, and then tell the system software to compensate by running the screen upside down.
systemd is the preferred method of starting applications on startup, but it is also one of the most complicated to use. With systemd, you have the benefit of being able to tell Linux to start certain programs only after certain services have started. As a result, it is a very robust tool for initializing your scripts and applications.
systemd is a relatively new suite of tools in the Linux world, and one of its intended purposes is to manage system processes after booting. When it was first released, systemd was meant to replace the init.d tool for starting programs. As of 2015, most of the major distributions include systemd, and since many kept init.d around for legacy support, you have the option of using either one. Be aware, however, that init.d may be deprecated, so systemd seems to be the future (for now).
A unit file is a plain text file that gives information to systemd about a service, device, mount point, etc. We"ll create a unit file that starts our program as a service (a process that runs in the background). Below are two examples of unit files: the first runs the blink.py example before the graphical desktop loads (useful for headless environments), and the second runs the clock.py example after the graphical desktop loads (useful if you are making a dashboard or GUI).
Feel free to change the Description as desired. The After key denotes when our program should run. multi-user.target is the system state where control is given over to the user (a "multi-user shell") but before the X Windows System is started. That means our program will run even without logging in! You can change this, depending on which services you need active before running your program (for example, network.target if you need networking). See here for a listing of all targets.
If your program requires graphical components (as in our clock.py example), then the following template is recommended for creating a systemd service.
Under [Service], we specify some environment variables. We want to connect to our primary display (this assumes only one display is connected to our Pi), so we set DISPLAY to :0, and we tell our application where to find the necessary credentials to use the X windows system with XAUTHORITY. ExecStart is the command we want to run (starting our Python clock program, in this case).
Unfortunately with systemd, we cannot tell exactly when the X system will start, and we cannot necessarily guarantee that a user will be logged in (unless you have enabled auto-login with sudo raspi-config). To account for this, we will brute force our program to restart (with Restart) every 10 seconds (with RestartSec) if it fails or exits. KillMode tells systemd to kill off any processes associated with our program if the service fails (or exits), and TimeoutSec=infinity means that we don"t ever want to stop trying to execute our program.
This starts a new bash shell, runs your program, and redirects the output (stdout) to a new clock.log text file. The 2>&1 command says that any errors (stderr) should also be redirected (written to) the same log file. Any output (e.g. from Python print() commands) or errors will then be saved to clock.log. You can view the log with the following command (note that you might need to stop the service and program before viewing the log):
Because your systemd unit file will likely run before .bashrc can alias the command python to Python 3, you might need to explicitly call the python3 command. To do that, just make sure that your call to Python is an absolute file location, for example, /usr/bin/python3.
For some services, like our clock.service example, you will need to stop the service before stopping the program. That"s because even if you stop the program (e.g. our Python GUI clock), the service will simply restart it 10 seconds later! To stop a service, enter the following command:
Note that stopping the service should send a stop command (SIGTERM--terminate signal) to your program. In most cases, this should stop the service and your program. If your program does not stop, see below on stopping your program.
ps -ax tells Linux to list out all the currently processes. We send that output to grep, which allows us to search for the keyword "python" (feel free to change it to the name of your program). Find the process ID (PID) number to the left of the listed process, and use the kill command to terminate that process:
In the previous project of the Raspberry Pi Series, I have shown you how to blink an LED using Raspberry Pi and Python Program. Moving forward in the series, in this project, I’ll show you the interfacing 16×2 LCD with Raspberry Pi.
In this project, you can see all the steps for Interfacing a 16×2 LCD with Raspberry Pi like circuit diagram, components, working, Python Program and explanation of the code.
Even though the Raspberry Pi computer is capable of doing many tasks, it doesn’t have a display for implementing it in simple projects. A 16×2 Alphanumeric Character LCD Display is a very important types of display for displaying some basic and vital information.
A 16×2 LCD is one of the most popular display modules among hobbyists, students and even electronics professionals. It supports 16 characters per row and has two such rows. Almost all the 16×2 LCD Display Modules that are available in the market are based on the Hitachi’s HD44780 LCD Controller.
The pin description in the above table shows that a 16×2 LCD has 8 data pins. Using these data pins, we can configure the 16×2 LCD in either 8 – bit mode or 4 – bit mode. I’ll show the circuit diagram for both the modes.
In 8 – bit mode, all the 8 data pins i.e. D0 to D7 are used for transferring data. This type of connection requires more pins on the Raspberry Pi. Hence, we have opted for 4 – bit mode of LCD. The circuit diagram (with Fritzing parts) is shown below.
The following image shows the wiring diagram of the featured circuit of this project i.e. LCD in 4 – bit mode. In this mode, only 4 data pins i.e. D4 to D7 of the LCD are used.
NOTE: In this project, we have used the 4 – bit mode of the 16×2 LCD display. The Python code explained here is also related to this configuration. Slight modifications are needed in the Python Program if the circuit is configured in 8 – bit mode.
The design of the circuit for Interfacing 16×2 LCD with Raspberry Pi is very simple. First, connect pins 1 and 16 of the LCD to GND and pins 2 and 15 to 5V supply.
Then connect a 10KΩ Potentiometer to pin 3 of the LCD, which is the contrast adjust pin. The three control pins of the LCD i.e. RS (Pin 4), RW (Pin 5) and E (Pin 6) are connected to GPIO Pin 7 (Physical Pin 26), GND and GPIO Pin 8 (Physical Pin 24).
Now, the data pins of the LCD. Since we are configuring the LCD in 4 – bit mode, we need only 4 data pins (D4 to D7). D4 of LCD is connected to GPIO25 (Physical Pin 22), D5 to GPIO24 (Physical Pin 18), D6 to GPIO24 (Physical Pin 16) and D7 to GPIO18 (Physical Pin 12).
The working of project for Interfacing 16×2 LCD with Raspberry Pi is very simple. After making the connections as per the circuit diagram, login to your Raspberry Pi using SSH Client like Putty in Windows.
Alternatively, you can use any VNC Viewer software like RealVNC. (NOTE: I’ve used RealVNC Software for accessing the Raspberry Pi’s Desktop on my personal computer).
I’ve created a folder named “Python_Progs” on the desktop of the Raspberry Pi. So, I’ll be saving my Python Program for Interfacing 16 x 2 LCD with Raspberry Pi in this folder.
Using “cd” commands in the terminal, change to this directory. After that, open an empty Python file with name “lcdPi.py” using the following command in the terminal.
Now, copy the above code and paste it in the editor. It is important to properly use the Tab characters as they help in grouping the instructions in Python.
Save the file and close the editor. To test the code, type the following command in the terminal. If everything is fine with your connections and Python Program, you should be able to see the text on the 16×2 LCD.
First, I’ve imported the RPi.GPIO Python Package as GPIO (here after called as GPIO Package) and sleep from time package. Then, I have assigned the pin for LCD i.e. RS, E, D4, D5, D6 and D7. The numbering scheme I followed is GPIO or BCM Scheme.
Finally, using some own functions like lcd_init, lcd_string, lcd_display, etc. I’ve transmitted the data to be printed from the Raspberry Pi to the 16×2 LCD Module.
By interfacing 16×2 LCD with Raspberry Pi, we can have a simple display option for our raspberry Pi which can display some basic information like Date, Time, Status of a GPIO Pin, etc.
Many simple and complex application of Raspberry Pi like weather station, temperature control, robotic vehicles, etc. needs this small 16×2 LCD Display.
I finally freed up one of my breadboards. I got my semi-permanent temperature sensing interface fully up and running with the Pi Cobbler – logging to COSM.
The next thing I wanted to get working was a 16 x 2 LCD panel. (£6 from Tandy) Having seen other people get these working, I figured it couldn’t be all that hard and it wasn’t too bad actually. But I did make one small mistake along the way. I got it working the second time I tried it.
The mistake I made was trying to run it from a separate 5 Volt supply instead of directly from the Pi. I hadn’t connected it to the Pi’s earth, which I think is why it didn’t work first time round. Properly grounded, I think it would run from a separate supply (but don’t connect the +ves together or the regulators will have a fight).
There are 3V3 (3.3 Volt) versions of these LCDs available, but the 5V ones are more common. According to my flavour-of-the-month site, Adafruit, it’s safe enough to use a 5 Volt LCD with the Raspberry Pi as long as the read-write pin (pin 5) is connected to ground. As long as we only “write” to the screen and don’t try to take input from it (like you would on some embedded device with input buttons e.g. a battery charger).
That way, you won’t “send” a 5 Volt signal to the Pi’s GPIO (General Purpose Input Output) ports, which run on 3V3. Sending a 5 Volt signal to a 3V3 port would be very likely to toast the port. This is the basis of the instructions I followed…
…but I didn’t use the Pi Cobbler this time as it’s already in use with my semi-permanent temperature logging setup. Once I get that onto a permanent board, the Cobbler will be free again.
I’ve noticed a few times that this screen sometimes needs the scripts to be run a couple of times before it works properly. I don’t have an explanation for that. Once or twice it has displayed what looks like Japanese characters instead of Roman alpha-numerics.
It might be that I haven’t used the Adafruit scripts properly, or it may be that they’re optimised for their own distro. No matter. On this occasion, the solution lay elsewhere. Eventually I switched to another driver by Matt Hawkins, from here.
Now this little LCD is displaying data pulled from my COSM temperature feed every 40 seconds. As I progressively add more sensors, I’ll be able to alternate the display, showing each set of readings for a few seconds before going on to the next. I’ve got plans for barometric pressure and light sensors already – who knows what else will crop up to occupy the remaining channels on the ADC? :rotfl: (Currently four channels available).