lcd display python quotation

display is quite smart, it could display many formats, but by default it uses __repr__ of the object you pass (but you could also define for example _repr_html_, _repr_json_ etc., check this for more information: https://ipython.readthedocs.io/en/stable/api/generated/IPython.display.html ).

It seems reasonable to guess that lcd_display_string() will output a string on the display. (Reading the documentation for the module you are using is recommended.)

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:

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:

Once you are done editing a demo_*.py file or writing your own Python script, follow the instructions on this section to run the script in the background. First, however, ensure that the script (e.g., script.py) has at least permission to be executed, as follows:

Connecting an LCD display to your Raspberry Pi is sure to take any project up a notch. They’re great for displaying sensor readings, songs or internet radio stations, and stuff from the web like tweets and stock quotes. Whatever you choose to display, LCDs are a simple and inexpensive way to do it.

In this tutorial, I’ll show you two different ways to connect an LCD to the Raspberry Pi with the GPIO pins. The first way I’ll show you is in 8 bit mode, which uses 10 GPIO pins. Then I’ll show you how to connect it in 4 bit mode, and that uses only 6 pins. After we get the LCD hooked up I’ll show you how to program it with C, using Gordon Henderson’s WiringPi LCD library.

I’ll show you how to print text to the display, clear the screen, position the text, and control the cursor. You’ll also see how to scroll text, create custom characters, print data from a sensor, and print the date, time and IP address of your Pi.

There’s another way to connect your LCD that uses only two wires, called I2C. To see how to do that, check out our tutorial How to Set Up an I2C LCD on the Raspberry Pi.

Most people probably want to connect their LCD in 4 bit mode since it uses less wires. But in case you’re interested, I’ll show you how to connect it in 8 bit mode as well.

In 8 bit mode, each command or character is sent to the LCD as a single byte (8 bits) of data. The byte travels in parallel over 8 data wires, with each bit travelling through it’s own wire. 8 bit mode has twice the bandwidth as 4 bit mode, which in theory translates to higher data transfer speed. The main downside to 8 bit mode is that it uses up a lot of GPIO pins.

In 4 bit mode, each byte of data is sent to the LCD in two sets of 4 bits, one after the other, in what are known as the upper bits and lower bits. Although 8 bit mode transfers data about twice as fast as 4 bit mode, it takes a longer time for the LCD driver to process each byte than it takes to transmit the byte. So in reality, there isn’t really a noticeable difference in speed between 4 bit mode and 8 bit mode.

WiringPi is a C module that makes it easy to program the LCD. If you already have WiringPi installed on your Pi, you can skip this section. If not, follow the steps below to install it:

To use different pins to connect the LCD, change the pin numbers defined in lines 5 to 14. You’ll need to convert the WiringPi pin numbers to the physical pin numbers of the Raspberry Pi. See here for a diagram you can use to convert between the different numbering systems.

To use the LCD in 4 bit mode, we need to set the bit mode number to 4 in the initialization function (line 20 below). The following code prints “Hello, world!” to the screen in 4 bit mode:

By default, text is printed to the screen at the top row, second column. To change the position, use lcdPosition(lcd, COLUMN, ROW). On a 16×2 LCD, the rows are numbered from 0 to 1, and the columns are numbered from 0 to 15.

The function lcdClear(lcd) clears the screen and sets the cursor position at the top row, first column. This program prints “This is how you” for two seconds, clears the screen, then prints “clear the screen” for another two seconds:

Each LCD character is a 5×8 array of pixels. You can create any pattern you want and display it on the LCD as a custom character. Up to 8 custom characters can be stored in the LCD memory at a time. This website has a nice visual way to generate the bit array used to define custom characters.

To print a single custom character, first define the character. For an example of this see lines 12 to 19 below. Then use the function lcdCharDef(lcd, 2, omega) to store the character in the LCD’s memory. The number 2 in this example is one of the 8 locations in the LCD’s character memory. The 8 locations are numbered 0-7. Then, print the character to the display with lcdPutchar(lcd, 2), where the number 2 is the character stored in memory location 2.

As an example to show you how to display readings from a sensor, this program prints temperature and humidity readings to the LCD using a DHT11 temperature and humidity sensor. To see how to set up the DHT11 on the Raspberry Pi, see our article How to Set Up the DHT11 Humidity Sensor on the Raspberry Pi.

Hopefully this helped you get your LCD up and running on your Raspberry Pi. The programs above are just basic examples, so try combining them to create interesting effects and animations.

If you have any problems or questions about installing the LCD or programming it, just leave a comment below. And don’t forget to subscribe to get an email when we publish new articles. Talk to you next time!

If you are like me, you might have a bunch of different components laying around the house that aren"t doing much but collecting dust. I decided to build this for my daughters room, so maybe someone else can enjoy building it if they are looking for a simple project to learn python or the Raspberry Pi.

In Python, any line of instructions containing the # symbol ("pound sign" or "hash") denotes the start of a comment. The rest of the line will be ignored when the program is run. Here is an example.

Because the second line started with a # sign, Python totally ignored that line, and as you can see, the number 2 was not printed. Common uses for comments include:

What if you want to include the quote character " inside of a string? If you try to execute print("I said "Wow!" to him") this causes an error: the problem is that Python sees one string "I said " followed by something Wow! which is not in the string. This is not what we intended!

You can put a backslash character followed by a quote (\" or \"). This is called an escape sequence and Python will remove the backslash, and put just the quote in the string. Here is an example.

I recently received a new Raspberry Piand wanted to create an Intro to Raspberry Pi project. My Pi included a 16x2 LCD display and a Wi-Pi Card so I created the Wireless Raspberry Pi Powered Joke Machine. Just press the push-buttons and the machine will look up a one-liner and scroll through it. (Admission of guilt here...I originally thought it would be neat to create a desk-toy that could display inspiring and educational famous quotes...the Joke Machine cando this, but when I found I could just as easily generate one-liners, I decided that would be more fun :-) )

This Step by Step Instructable walks you through the process of setting up a new Raspberry Pi, adding the the PiFace Control and Display LCD, the WiPi wireless and the provided python script TheQuoteMachine.py which looks up jokes and quotes on a free service called iheartquotes.com. it"ll also describe how to access your Pi without need for a keyboard or Display using VNC remote access.

Python is already installed on the Raspberry Pi, so to run my Quote Machine script you simply need to Download the script from instructables.com (to your Raspberry Pi)

Now you can run /home/pi/bin/TheQuoteMachine.py  It will connect to the free service http://www.iheartquotes.com and display hilarious one-liners. It does this by running a URL that returns the one-liners back in straight text, splitting the text up into 16 character wide segments and then monitoring the PiFace button events that let you scroll up and down through those segments.

Button 4 is the Quit ButtonInstall Your Quote Machine in a Project Box -steps vary depending on the box you use I used a Sharpie to mark where the LCD display should be mounted on the project box

Im having an issue it might be because I don"t have the pi face installed into it yet but the code Chomd +x /home/pi/TheQuoteMachine.py it doesn"t work I tried to run it in the terminal and python0

The Canadian mechanical engineering student hacked the dashboard display screen in his car, so it’s now displaying funny quotes from Reddit. Specifically, it’s displaying those weird “Shower Thoughts” — the headlines from Reddit’s forum for the brilliant one-off insights that pop into your head at random moments.

“I have no programming experience other than a few Arduino projects around the house,” De Mel wrote in a blog post, “so my code is definitely not optimal.” But within one month, he’d already finished the project, and shared its Python code on GitHub. “Hopefully, this will at least give you some kind of starting point for your own project, and you will be able to see the underlying process for making this work.”

Luckily, all the digital devices in his 2012 Hyundai Genesis Coupe were connected using a fairly common standard — the “Controller Area Network bus” (or CAN bus). So Harin grabbed one of his Arduino’s — plus a cheap SPI CANBUS circuit board — and just started doing some experiments. When he first installed his Arduino circuit board into the dashboard, the LCD began showing the time of day — every ten milliseconds — and any new messages that he sent to the screen were simply being wiped out when the system re-transmitted. But Harin had already built up a strong motivation to keep moving forward, according to a recent write-up in Make: magazine, because “I hated that stupid little blue LCD. It would just sit there staring at me brightly with the words ‘AUX’…”

So he re-routed the LCD’s input. And fortunately, Harin’s other Raspberry Pi board could accommodate a WiFi dongle. By using an iPhone for connectivity, it was now able to draw down the funny Reddit quotes. And Make: also reported that his next project may be to install a router directly into his car.

Harin’s even mounted his Nexus 7 Android tablet into his car’s dashboard and is using it to play music. In the comments on his blog, he talks about one day transmitting the “now playing” information from the tablet to the LCD. Somewhere in the mix, there’s even an SQL database. “My main script retrieves the top post from Shower Thoughts and converts the characters to their hexadecimal equivalents, adds the message ID and row identifier, and stores it in an SQL database.”

There’re two more scripts just for retrieving the quote from the database and display it on the screen, which Harin says will be building blocks for more features down the road. “Eventually, I’ll be able to screen the messages intended for the LCD on the primary [CAN bus] network and add the ones I want to keep to the SQL database while removing the ones I don’t need anymore.”

Now instead of seeing the external temperature on his display, he sees bits of mind-blowing amateur philosophy. But maybe it goes to show you that if you’re going someplace strange, your journey there can be just as unpredictable. According to his blog post, the screen was originally intended for displaying song information (title and artist) for Sirius XM.

It can display a number in just about any size. It can display decimal, hexadecimal, octal or binary numbers. It is easy to connect to data sources using the display() slot, which is overloaded to take any of five argument types.

QLCDNumber emits the overflow() signal when it is asked to display something beyond its range. The range is set by setDigitCount() , but setSmallDecimalPoint() also influences it. If the display is set to hexadecimal, octal or binary, the integer equivalent of the value is displayed.

These digits and other symbols can be shown: 0/O, 1, 2, 3, 4, 5/S, 6, 7, 8, 9/g, minus, decimal point, A, B, C, D, E, F, h, H, L, o, P, r, u, U, Y, colon, degree sign (which is specified as single quote in the string) and space. QLCDNumber substitutes spaces for illegal characters.

It is not possible to retrieve the contents of a QLCDNumber object, although you can retrieve the numeric value with value() . If you really need the text, we recommend that you connect the signals that feed the display() slot to another slot as well and store the value there.

Constructs an LCD number, sets the number of digits to 5, the base to decimal, the decimal point mode to ‘small’ and the frame style to a raised box. The segmentStyle() is set to Outline .

Constructs an LCD number, sets the number of digits to numDigits , the base to decimal, the decimal point mode to ‘small’ and the frame style to a raised box. The segmentStyle() is set to Filled .

This property corresponds to the nearest integer to the current value displayed by the LCDNumber. This is the value used for hexadecimal, octal and binary modes.

Corresponds to the current display mode, which is one of Bin , Oct , Dec (the default) and Hex . Dec mode can display floating point values, the other modes display the integer equivalent.

Corresponds to the current display mode, which is one of Bin , Oct , Dec (the default) and Hex . Dec mode can display floating point values, the other modes display the integer equivalent.

The Internet is full of real time data. Weather information, stock quotes, etc, can be obtained from different service providers. Since most of the Raspberry Pi computers come with Wifi, and it’s extremely easy to handle the data obtained from the Internet with Python, it makes sense to use Raspberry Pi to fetch data from the Internet automatically.

On the other hand, every Raspberry Pi comes with GPIOs, which can be used to connect different devices. For example, we can connect a 16 x 2 character LCD display to the Raspberry Pi.

A communication interface called I2C is frequently used by many devices. Any I2C device uses 4 pins: one for power, one for the ground, one for data (“SDA”) and one for clock signals (“SCL”). For instance, this character LCD display can be connected to Raspberry Pi or other microcontroller via I2C.

This all sounds complicated. Fortunately, Adafruit has created the CircuitPython library for the Raspberry Pi. With this library, we can use I2C devices on Raspberry Pi very easily.

To achieve the above learning outcomes, we will use a Raspberry Pi Zero W to fetch some weather data from the Internet, and display the fetched data on a character LCD screen:

We usually use a browser to look for information on the Internet. We type a URL in the browser, and the browser will display an HTML page. However, if you look at the source of a HTML page, you will see that HTML is actually kind of messy.

Next, we are going to install two Python libraries: Adafruit’s CircuitPython and the library for the LCD1602 display. Let’s create a new folder on the Raspberry Pi for this project inside the terminal.

NOTE: We only need cd_api.py and circuitpython_i2c_lcd.py only, so it’s better to just copy the python scripts and not to install the entire library.

The requests library enables us to send HTTP requests to a web server. The most frequently used HTTP method is GET. Everytime you enter an URL in a browser, you send an HTTP GET request to a web server, and the server respond to the request by sending the HTML data back to the browser. The get method in the requests library does the same thing, only this time Python does the work for you.

Both board and busio are from the CircuitPython library. As you will see in a minute, you don’t need to worry about typing the wrong pin numbers when you initialize an I2C device if you use the CircuitPython library. Also, we import the I2cLcd class and the sleep function.

This is where the CircuitPython really shines: the exact same code can be used in other microcontrollers running CircuitPython! So if you get yourself a Circuit Playground Bluefruit, you can use the character LCD display with the exact same code.

DEFAULT_I2C_ADDR = 0x27 defines the address of character LCD display. Every I2C device has an address. This address is important because multiple I2C devices can be connected to the Raspberry Pi, and the Raspberry Pi needs that address to communicate with the device correctly. Finally, we create an instance of I2cLcd with the i2c object, the I2C address, the number of rows and the number of columns as the parameters for the constructor. The backlight is turned on by calling the backlight_on method.

NOTE: This particular LCD1602 display’s address is 0x27, but yours may have a different one. You may need to call busio.I2C.scan() to check the actual address, as described in this Adafruit guide.

Next, rather than printing out all the JSON data in the console, we extract the information that we want and display it on the LCD display. For example, we can just display the temperatures in different regions. Replace print(data) with the following lines of code:

This method actually parses the JSON string from the HTTP response, and returns the corresponding Python object. Thus, we can use the data inside the object as usual:

For each entry in the temp_data array, we first clear the display by calling clear(). Then, we move the cursor to (0, 0), i.e. the first position in the first row, and display the first 16 characters of the ‘place’ entry (a string) in the first row. Similarly, we move the cursor to (0, 1), i.e. the first position in the second row, and display the ‘value’ entry (a number). Finally, we pause the program for 2 seconds before showing the next entry.

NOTE: To get the first 16 characters of the ‘place’ string, we use the substring functionality of Python. You can understand more about this by reading this introduction from w3schools.

lcd.display(image[, x=0[, y=0[, x_scale=1.0[, y_scale=1.0[, roi=None[, rgb_channel=-1[, alpha=256[, color_palette=None[, alpha_palette=None[, hint=0[, x_size=None[, y_size=None]]]]]]]]]]]])¶