Introduction Inky Phat

Inky pHAT is a small, low-cost display designed for use with the Raspberry Pi single board computer. It is made by Pimoroni, a company based in the UK that produces a range of hardware and software products for the Raspberry Pi.

Inky pHAT is a flexible display that can be used for a wide range of projects, such as creating a digital picture frame, displaying weather information, or even building a simple e-ink clock. It is particularly useful for projects that require a low-power display that can be easily read in any lighting conditions.

One of the main features of Inky pHAT is its E-Ink display, which uses electrostatic charges to change the color of tiny particles suspended in a liquid. This allows the display to be very energy efficient, as it uses very little power to maintain an image once it has been displayed.

Overall, Inky pHAT is a useful tool for anyone looking to add a low-power display to their Raspberry Pi projects. Its E-Ink display and small size make it a versatile and convenient choice for a wide range of applications. Inky pHat is an e-paper display with a dedicated controller in the PCB. Plug and play! And big thanks for the excellent documentation.

From the Pimoroni site

Inky pHat by Pimoroni is easy to use ‘phat’ A HAT is an extension for the Raspberry Pi platform. Hardware attached on top or HAT. With the sturdy HAT construction, there a three benefits;

• No soldering; plug it onto the Raspberry Pi.
• Robust mechanical design, it can handle a school environment.
• ‘Autoconfiguration,’ all the software is provided. Just attached and install. ‘Plug and play/pray.’

I am happy with the HAT-system. It just works, no tinkering and no failure with a faulty connection. The design can handle some rough handling (always be careful when handling hardware!), and with the software backend from the manufacture, it’s just a few commands in the CLI, and it works. Most of the times 😉

Tip 1 how to update Raspberry Pi

It’s always good to work with an updated Raspberry Pi. Sudo apt-get update, sudo apt-get upgrade. It will take some time when this is the first time you are using their commands. Keep in mind; these commands are going to be typed into the terminal or SSH. To keep things organized, I always end the update sessions with sudo apt-get autoclean. This removes all the no longer used files after an update.

Tip 2 Please use a stable power supply

It sounds like a normal thing to do, right… but I found out the hard way that this needs some TCL. The Raspberry Pi was giving strange errors, rebooted, and shutdown for no apparent reason. The installation on the sd-card went corrupt, and I couldn’t find the problem. I swapped the card, reinstalled the OS on the card, and even swapped Raspberry Pis. And with some deduction, Sherlock would be proud; I discovered a faulty power supply to be the problem. Double-check the quality of the Micro USB cable! And be careful when installing the Inky pHat. The pins of the Raspberry Pi and Inky pHat need to be aligned. DO-NOT-FORCE.

Tip 3 How to install software with CLI

The documentation by Pimoroni is excellent. Getting Started With Inky pHat is a great start. It helps with the correct commands for the CLI. Again, this display is a command-line interface only. It’s a quick installation with a few commandos. I’ve summarized the commands under this text block. The dollar ($) sign is a new line on the CLI. Keep in mind; this is a United Kindom based company. And over there, color is spelled with ‘ou.’ ;-).

$ curl https://get.pimoroni.com/inky | bash
$ cd /home/pi/Pimoroni/inky/examples
$ python name-badge.py --type "auto" --colour "red" --name "Ramon"

Tip 4 Automate the sh*t with CRON

CRON is the automation tool in Linux. It’s ‘easy’ to use. I had a few challenges when I wanted to automate the update of the display. CRON was for me. I never used it. This resource helped me a lot! I started with calling the python script directly from CRON. After a few failures, I found that CRON does understand .sh scripts. This is my .sh script. I called it phat.sh. Open a new file with nano phat.sh. Be in the root of your folders; cd is the command to return to the root. Exit nano with ctrl+x and save (!) the file. After saving, make the file executable. Type in the same folder as the phat.sh : chmod +x phat.sh

#!/bin/bash
cd /home/pi/Pimoroni/inky/examples/phat/
python weather-phat.py --colour red

In the CRON tab, I added the following. The /10 executes the script every 10 minutes (starting at .0 every hour)—only between 8 and 22 hrs. The bash is used to run the script. Pay attention to the absolute path with a / at the beginning.

*/10 8-22 * * * * bash /home/pi/phat.sh

Tip 5 This works, what’s next?

And how what? You have a mobile weather station. It runs from a power bank or even a dedicated battery. I’m going to install it on the fridge with a micro USB cable to provide power. With the 10-minute update cycle, the screen isn’t heavily used and will work for quite some time.