Adafruit IOT IR Remote using Raspberry Pi Zero W User manual

IOT IR Remote using Raspberry Pi Zero W and QtPy Hat

Created by Chris Young

Last updated on 2021-04-30 02:30:46 PM EDT

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Guide Contents

Guide Contents Overview

Project History

Parts Required

Raspberry Pi Items QT Py and Accessories QT Py Hat Board and Components You can submit the board files to your favorite board manufacturer, make the board yourself or you can also order the board directly from the following vendors Other items

QT Py Hat Assembly

Optional Features

QT Py Software

Download the Software Installing IRLib2

Testing the QT Py Hat

Testing the Receivers

Raspberry Pi Zero W Software and Setup

Setting up the Raspberry Pi

Installing NOOBS Connecting to Wi-Fi Initial Configuration Enabling Samba Server Installing Files Installing Flask Disabling Bluetooth Testing the Python App

Final Configuration Steps

Programming Custom IR Codes What If It Does Not Decode? Final Steps

3D Printed Case

Overview

In this project, we will create an infrared remote control for your TV, cable box, DVR, Blu-ray, or another similar consumer electronic device. The remote control is operated by a webpage interface. The Raspberry Pi serves the webpage over your local Wi-Fi network. You can access it on your PC, laptop, tablet, or phone as long as it is connected to your local Wi-Fi network.

The ability to control your TV or cable/DVR and other devices over a webpage is a very popular idea that has led to some commercially available products. Such products are often expensive, limited in their customization capabilities, and often dependent upon cloud-based services that can be a security risk and may not survive the useful life of the product.

These devices are especially useful as an assistive technology device for a person with a disability such as me. Someone with limited strength and hand dexterity often cannot use a traditional remote control. The ability to use a web interface is a handy alternative to a traditional remote because it also allows leveraging the power of other assistive technology solutions such as eye gaze, speech recognition, and AT switch control which the user may already have implemented for accessing the internet.

It is based on a Raspberry Pi Zero W and Adafruit QT Py-SAMD21. The QT Py is soldered to a custom open-source Hat that attaches to the Raspberry Pi Zero W.

The board, called the QT Py Hat, was designed by Bill Binko. The Hat also contains infrared transmit and receive circuitry. The Raspberry Pi communicates with the QT Py through the UART RX and TX pins via the hat. There is also the option to connect I C or SPI interfaces of the two boards through the hat via various jumpers.

Although a Raspberry Pi on its own could do infrared output, it would have to do so via bit-bang because it cannot do PWM output to the IR LED driver circuit. It would require complicated drivers. It ties up the processor which could cause an interruption in other activities such as Wi-Fi data coming and going. By handing off the IR processing to the QT Py, it simplifies the entire process and makes it more reliable.

The combination of Raspberry Pi and QT Py provides for a variety of other potential uses such as adding analog I/O to the Raspberry Pi. We will only be concentrating on the infrared aspects of this system but future software updates will make it easier to use the other functions of the QT Py as well as its STEMMA QT interface.

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Here is a YouTube video demonstrating how the device works to control my TV and Cable DVR box. Note it can be reconfigured for most any consumer electronic device such as a Blu-ray player or even an old VCR that uses an infrared remote.

Project History

Here's a brief personal history of how this project came to be. It's not necessary to know this to build the project but I thought you might find it interesting.

Several years ago I purchased a commercially available web-based IR remote called a "RedEye Remote" however its web interface was dependent upon a cloud-based server. When the company went bankrupt, the device became a useless brick. Then I developed my own solution using an Arduino compatible board called Pinochio. (That's how they spelled it to avoid potential trademark infringement.) It was an early system providing IoT capabilities. Unfortunately, it too relied on a cloud service that eventually disappeared.

My next solution was to use an Arduino Yún which was the first official Arduino product supporting IoT. It consisted of a small Linux system running WRT and was interfaced with what was essentially an Arduino Leonardo based on the ATMEGA 32u4. My infrared transmit and receive library IRLib2 already supported the 32u4 so it was a natural choice although somewhat expensive at approximately $75.

The Yún was eventually discontinued. Fortunately, my solution did not rely on any cloud-based systems and was based entirely on my local Wi-Fi system so it continues to work to this day. There is now a revision 2 of the Yún that sells for about $56 which is still a little bit expensive.

I was recently contacted by Ean Price who works with an organization that provides assistive technology solutions to people in Canada. He had seen a video I did about various assistive technology gadgets I have built and among them was the Yún-based device. He wanted to build one for himself and perhaps as many as 5 more people. Long-term he speculated they might create as many as 50 of the devices.

After a brainstorming session with Bill Binko of ATMakers.org (https://adafru.it/RF6), we concluded that the Yún was expensive old technology and if we were going to be assisting lots of clients with such devices we could come up with a simpler more cost-effective solution. The result is the QT Py Hat project we present here.

Although designed to be an IR remote, it also is an extremely cost-effective alternative to the Yún. It does not yet have the software support of the Yún but we will be working to develop this platform further in the near future.

Parts Required

Here is a list of everything you will need for this project.

Raspberry Pi Items

Although this project can use any Raspberry Pi that has Wi-Fi capability which includes the various varieties of models 3 and 4, we recommend the Raspberry Pi Zero W or Raspberry Pi Zero WH. The "WH" is identical to the "W" model except that it has the headers pre-soldered. If you already have 2 x 20 pin headers available you can save $4 and solder them yourself.

Raspberry Pi Zero WH (Zero W with Headers)

If you didn't think that the Raspberry Pi Zero W could possibly get any better, then boy do we have a pleasant surprise for you! The new Raspberry Pi Zero... $14.00 In Stock

You will need a 5V power supply. We recommend this 2.5 amp supply with a micro USB cable already attached.

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5V 2.5A Switching Power Supply with 20AWG MicroUSB Cable

Our all-in-one 5V 2.5 Amp + MicroUSB cable power adapter is the perfect choice for powering singleboard computers like Raspberry Pi, BeagleBone or anything else that's power... $7.50 In Stock

You will need a microSD card for the operating system. It should be at least 8Gb. You will need the capability of reading and writing information to this card from your PC or laptop. Although you can purchase an SD card with the NOOBS operating system preinstalled, we have not used that method and so the procedures we outline here will not exactly be the same. So we recommend getting a plain card and downloading NOOBS yourself.

Add to Cart

SD/MicroSD Memory Card - 16GB Class 10 - Adapter Included

Add speedy mega-storage in a jiffy using this 16 GB Class 10 micro-SD card. It comes with a SD adapter so you can use it with any of our shields or adapters! Preformatted to FAT so it... $19.95 In Stock

We will be configuring the Raspberry Pi Zero W as a "headless" device. That means it will not need a monitor, keyboard or mouse. If you intend to use the Pi Zero W for other purposes you might want to consider getting an HDMI cable, Mini-HDMI to HDMI adapter, USB OTG cable, and USB Console cable as recommended on the Raspberry Pi Zero W product page (https://adafru.it/vMD).

QT Py and Accessories

This project is designed to work with the Adafruit QT Py-SAMD21. In addition to the board itself, you will also need a USB C cable for programming it.

Note that the QT Py Hat has been designed with the upcoming RP 2040 version of the QT Py board in mind however, the software included in this tutorial is not compatible with the RP 2040 because it uses the Arduino IDE C++ as well as IRLib2 neither of which currently support the RP 2040. The IRLib2 library may eventually support the RP 2040 processor and we will update the software when that capability is available.

Your browser does not support the video tag. Adafruit QT Py - SAMD21 Dev Board with STEMMA QT

What a cutie pie! Or is it... a QT Py? This diminutive dev board comes with our favorite lil chip, the SAMD21 (as made famous in our GEMMA M0 and Trinket M0 boards).For... Out of Stock

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USB Type A to Type C Cable - approx 1 meter / 3 ft long

As technology changes and adapts, so does Adafruit. This USB Type A to Type C cable will help you with the transition to USB C, even if you're still... $4.95 In Stock

Although not necessary for this project, you might also want to consider getting the 2 MB SPI 8 pin addon memory chip. The QT Py Hat board has a hole in it to accommodate this chip which might be useful for future projects.

Out of

Stock

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GD25Q16 - 2MB SPI Flash in 8-Pin SOIC package

These little chips are like miniature SSD drives for your electronics. When you don't need something with as much storage as a micro SD card, but an EEPROM is too small, SPI (or... $1.25 In Stock

QT Py Hat Board and Components

The QT Py circuit board is an open-source board. The Eagle CAD files for the board are available in a GitHub repository that you can download at the button below. The same repository also contains all of the software necessary for the project as well as STL files for a 3D printed case. You should download it now for later use.

https://adafru.it/RF7

You can submit the board files to your favorite board manufacturer, make the board yourself or you can also order the board directly from the following vendors

QT Py Hat at PCBWay.com (https://adafru.it/RF8) QT Py Hat at OSHPark.com (https://adafru.it/RF9)

Here are images of the board and schematics.

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https://adafru.it/RF7

You will also need a number of through-hole components. Most of the parts you will need are available from Adafruit. Some that are not available at Adafruit are available from a variety of suppliers. At the end of this list will give you a complete list of through-hole parts available from Digi-Key.

First, we will need 2 IR LEDs. We prefer to use a combination of wide-angle and narrow-angle LEDs. This narrow 20° angle LED is available from Adafruit. A 40° wide-angle LED is available from Digi-Key. See the Digi-Key parts list at the end.

Super-bright 5mm IR LED

Infrared LEDs are used for remote controls (they're the little LED in the part you point at your TV) and 'night-vision' cameras, and these little blue guys are high powered... $0.75 In Stock

You will also need an NPN transistor and 2 PNP transistors. Here Adafruit has a combo pack of five of each or you can buy them separately in packs of 10.

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Bipolar Transistor Kit - 5 x PN2222 NPN and 5 x PN2907 PNP

Transistors are powerful little electronic switches, and we really like these NPN and PNP transistors whenever we need to control medium-power electronics, such as small motors,... $1.95 In Stock

You will need a 1K ohm resistor and optionally you may need two 33 ohm resistors. Adafruit carries the 1K variety but if you need the 33 ohm see the Digi-Key parts list at the end of the page. We will explain later why you may or may not need the 33 ohm resistors.

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Through-Hole Resistors - 1.0K ohm 5% 1/4W - Pack of 25

ΩMG! You're not going to be able to resist these handy resistor packs! Well, axially, they do all of the resisting for you!This is a 25 Pack of... $0.75 In Stock

You will need an infrared receiver such as this TSOP38238 from Adafruit. In the Digi-Key parts list, we specify a TSOP38438 which has a slightly better automatic gain control circuit however the 38238 from Adafruit will work fine under most every circumstance. You may also need an infrared learner device the TSMP 58000 from Digi-Key. We will explain later why you might need a TSMP58000.

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Adafruit IOT IR Remote using Raspberry Pi Zero W User manual

Specifications and Main Features

Frequently Asked Questions

User Manual