Building an Air Quality Monitor with ANAVI Infrared pHAT and MH-Z19

Takuya Matsuyama, a developer from Japan making a Markdown note-taking app called Inkdrop, published a wonderful tutorial how to build an air quality monitor using Raspberry Pi Zero W, ANAVI Infrared pHAT and MH-Z19B NDIR infrared gas module.

How to build an air quality monitor using Raspberry Pi Zero W + ANAVI Infrared pHAT

MH-Z19B is an intelligent infrared CO2 module which interacts with the Raspberry Pi using UART (universal asynchronous receiver-transmitter). Takuya uses the UART port on ANAVI Infrared pHAT to attach MH-Z19B. The rest of the sensor modules for his setup are included in ANAVI Infrared pHAT Advanced kit: HTU21D for temperature and humidity, BMP180 for barometric pressure and BH1750 for light.

By the way, initially we had published open source examples for using HTU21D, BMP180 and BH1750 in the C programming languages using the library wiringpi. Takuya also based his setup on wiringpi. However, wiringpi is now deprecated therefore we have replaced it with another library called libi2c-dev. Furthermore we added examples written in Python 3.

AI-Thinker – a Trusted Supplier During the Global Chip Shortage

AI-Thinker is a leading supplier of IoT wireless products and solutions, including antennas, modules and RF lab service. Since 2017 we have been using AI-Thinker ESP-12E modules with ESP8266 in many of our open source hardware products, including ANAVI Fume Extractor, ANAVI Gas Detector, ANAVI Thermometer, ANAVI Light Controller and ANAVI Miracle Controller.

AI Thinker modules with ESP8266

Now, despite the hard times of global chip shortage, AI-Thinker keeps manufacturing and delivering high-quality modules on time. As a trusted supplier through the years, recently we have purchased from AI Thinker enough ESP-12E modules do fulfill the demand and keep making our open source hardware products.

AI Thinker modules with RISC-V microcontroller

Furthermore we stocked ESP-C3-12F modules with Espressif Systems ESP32-C3 Wi-Fi microcontroller based on the open standard instruction set architecture (ISA) RISC-V. ESP-C3-12F are pin to pin compatible with ESP-12E.

AI Thinker ESP32

AI-Thinker is based in Shenzhen, China. The company was founded 10 years ago, in 2012. They also provide LoRaWAN, NB-IoT, Bluetooth and other Wi-Fi modules.

ANAVI Gardening uHAT: Safety First

Earlier in January all ANAVI Gardening uHAT kits were delivered to the Crowd Supply warehouse and soon after that Crowd Supply team sent them to their final destination: our valuable and trusting crowdfunding backers! Thank you again for the support.

ANAVI Gardening uHAT Developer Kit
ANAVI Gardening uHAT Developer Kit

ANAVI Gardening uHAT is a versatile development board, so please follow the instructions below for safe use:

  • ANAVI Gardening uHAT should only be connected to a compatible Raspberry Pi with 40-pin header.
  • Do not expose it to water or moisture, and do not place it on a conductive surface whilst in operation.
  • Do not expose it to heat from any source; it is designed for reliable operation at normal room temperatures.
  • Take care while handling the board to avoid mechanical or electrical damage to the printed circuit board and connectors.
  • Avoid handling ANAVI Gardening uHAT while it is powered on. Only handle by the edges to minimize the risk of electrostatic discharge damage.

In the meantime, there is a work in progress going on the user’s manual which is available at GitHub. We will soon update it. As usual, GitHub pull requests with improvements and fixes to the documentation or the source code examples are always welcome.

ANAVI Gardening uHAT: Shipping Soon

At the beginning of January all ANAVI Gardening uHAT kits were shipped to the Crowd Supply warehouse. We are happy we managed to do it ahead of schedule. Even Tux, the mascot of the Linux kernel, helped out with the transportation.

In the coming weeks, the crowdfundng orders will be prepared for shipment to backers. A tracking number when the order ships.

ANAVI Gardening uHAT
ANAVI Gardening uHAT

Thanks for your patience and support for this open source hardware project! We hope you will enjoy and have a lot of fun with ANAVI Gardening uHAT!

ANAVI Gardening uHAT Manufacturing Progress

We have good news regarding ANAVI Gardening uHAT! All boards have been received almost fully assembled from the local factory and we have sourced all required peripherals.

Recently, we received the last batch of assembled printed circuit boards from the local factory. As you can see on the photo, only the EEPROM is missing. We will flash and solder it in-house.

The winter is coming… Grab a ANAVI Gardening uHAT for your Raspberry Pi

We have also received additional peripherals, which will be included in ANAVI Gardening uHAT Starter, Advanced, and Developer kits. On the photo you can see the big packages with analog capacitive soil moisture sensor. Each kit will contain a couple of capacitive soil moisture sensors.

Capacitive Soil Moisture Sensor v1.2

The recyclable cardboard boxes for our eco-friendly packaging have also already been delivered. Another local company here in Plovdiv, Bulgaria will print all stickers for us. We expect them next week.

Our crowdfunding campaign recently ended very successfully but you can still order our open source Gardening uHAT for your Raspberry Pi and be among the very first owners!

ANAVI Fume Extractor Assembly Guide

ANAVI Fume Extractor is an  open source smart solder smoke absorber useful for makers during soldering. It comes as a do-it-yourself kit. There are 3 types of kits with different sensor modules. ANAVI Fume Extractor is available at Crowd Supply, Mouser and Tindie.

ANAVI Fume Extractor video assembly guidelines

This tutorial explains the exact steps of how to assemble the ANAVI Fume Extractor developer kit which contains all supported peripherals. The whole process can take up to 30-40min. A screwdriver is required. It is highly recommended to watch the video with the assembly guidelines before you start.

Step 1: Peel off the protective films

Each ANAVI Fume Extractor kit contains 4 acrylic enclosures. Peel off the protective films from both sides of all of them. The acrylic enclosure will be clear and transparent once the film is peeled off.

Step 2: PCB

Attach the ANAVI Fume Extractor printed circuit board to the bottom acrylic enclosure with 4 screws and 8 nuts. Add 4 nuts below and 4 nuts above the board.

Step 3: Mini OLED Display

The kit includes 4 M2 screws and nuts as well as appropriate washers. Remove the protective film from the mini I2C OLED display. Carefully attach the display to the front acrylic case as shown in the video. The display is fragile. Don’t fasten the screws too tight!

Step 4: Fan Filter

A couple of fan filters are included in each kit. Attach the 4 M4 screws to the front acrylic enclosure with 4 of the M4 nuts. Place one of the filters. Leave the other one as a replacement.

For long-term maintenance over time the filter must be regularly replaced. There is a huge variety of 80mm fan filters on the market. It is up to you to decide whether to buy carbon or HEPA filters. Various distributors offer appropriate filters, for example Mouser has 80 mm, 45 PPI foam media filters.

Step 5: Fan

Add the acrylic enclosure that separates the fan from the filter. On the side of the fan you will notice a label that indicates the direction of the air flow. Place the 80mm 5V DC fan so that the air will flow through the filter.

Screw the 4 M4 20mm stand-offs to firmly fix the position of the fan.

Step 6 (optional): Light Sensor Module

Owners of a developer kit should add the BH1750 light sensor module to the front acrylic enclosure and fix it with one M4 screw and a nut.

Step 7: Peripherals

Connect peripherals, like the fan and the mini OLED display, to the printed circuit board. There are dedicated connectors for both of them. Pay attention to the labels for I2C on the top of the mini OLED display.

Step 8 (optional): Sensors

Owners of advanced or developer kits should attach:

  • MQ-135 for indoor air quality
  • HTU21D I2C sensor module for temperature and humidity
  • BMP180 I2C sensor module for barometric pressure and temperature.

Step 9: Assemble all acrylic enclosures

Finally, assemble together all acrylic enclosures by fastening 4 M4 nuts on the back of ANAVI Fume Extractor.

On the right side of ANAVI Fume Extractor you will notice a jumper for the WiFi as well as a button to switch the filter on and off. By default the jumper for the WiFi is set to OFF. Move it to ON and power cycle the board if you want to connect ANAVI Fume Extractor to a MQTT broker and IoT platform such as the popular open source system Home Assistant.

To turn ANAVI Fume Extractor on, gently plug an appropriate cable and 5V power supply into the microUSB connector on the left side of the board. The microUSB connector is used only for providing power, no data is transferred. Power supply and microUSB cable are NOT included in any of the kits.

For advanced or developer kits, on the first boot, it is very important to do what is called the “burn-in” procedure for initial calibration of MQ-135 air quality sensor module:

  • Place ANAVI Fume Extractor with the attached MQ-135 in a room with clean air
  • Leave it running for at least 24 hours

This has to be done only once when the MQ-135 sensor module is used for the first time. After doing this procedure, on every next boot ANAVI Fume Extractor and MQ-135 will do a quick calibration in a couple of minutes and start working properly.

MicroPython on Raspberry Pi Pico with Thonny IDE

Raspberry Pi Pico is a tiny and fast development board by the Raspberry Pi Foundation built using the brand new RP2040 32-bit dual ARM Cortex-M0+ microcontroller. The major advantage of Raspberry Pi Pico is the affordable price as it is available for about $4 (without taxes and shipping).

In this video tutorial you will learn how to get started with MicroPython using the open source Thonny IDE on Raspberry Pi Pico. Thonny runs on Mac, Windows and Linux distributions, in the video it is used on Ubuntu. The video includes Pico unboxing, MicroPython installation guide, blinking LED example, MicroPython REPL demo and conclusions.

Useful links:

The video tutorial was sponsored by PCBway which provide high-quality prototyping services. On the photo you can see prototypes of green printed circuit boards with white silkscreen following Raspberry Pi specifications for micro Hardware Attached on Top (uHAT).

ANAVI Gardening uHAT is now OSHWA certified

A few days ago we received an official confirmation that ANAVI Gardening uHAT has been certified as open source hardware by the Open Source Hardware Association with UID BG000079.

The Open Source Hardware Association (OSHWA) is a non-profit organization that supports the open source movement and maintains an open source hardware certification registry. OSHWA Certification provides an easy and straight-forward way to quickly check if a product complies with a uniform and well-defined standard for open source hardware.

Open source hardware certification guarantees the sharing of knowledge and keeps prices fairly based on the bill of materials of the hardware’s components. ANAVI Gardening uHAT hardware design files are available under CC BY-SA 4.0, which allows you to remix, transform, and build upon the material for any purpose, even commercially.

In a nutshell, OSHWA certifies a project as open source based on public access to four elements:

  • Hardware – functional elements of the product
  • Software – code, firmware, or other software involved in the product’s functionality
  • Documentation – including design files, schematics, and instructions
  • Branding – brand names, product names, logos, and product design

The exact certified version of each product receives a unique UID, for example, ANAVI Gardening uHAT is with UID BG000079. The prefix is the country code. We make our open source hardware in Plovdiv, Bulgaria, so the country code is BG. The suffix is a sequential ID number. At the moment, there are 79 certified open source hardware products from Bulgaria. For a comparison, the United States is leading with the amazing 2052 certified products, followed by Germany with 116. Bulgaria comes in at the third place, primarily thanks to our awesome open source neighbors from Olimex.

As a very small company we are all proud to have contributed to the Bulgarian success in this field. Hopefully, the popularity of the open source hardware movement will continue to increase worldwide.

ANAVI Gardening uHAT

ANAVI Gardening uHAT is a low-cost, open source Raspberry Pi add-on board that helps you develop smart solutions for monitoring and growing plants.

ANAVI Gardening uHAT supports multiple sensors for soil moisture, temperature, humidity, barometric pressure, and light. Getting started is easy: just plug it into a Raspberry Pi with your bare hands and follow the instructions in the user manual. No soldering is necessary, and no tools are required.

We hope you’ll jump in and help us bring this entirely open source gardening project to life by supporting our new crowdfunding campaign at Crowd Supply.

ANAVI Macro Pad 2 Developer Kit Assembly Guide

ANAVI Macro Pad is an open source, programmable two-key mechanical keyboard with backlighting. It was funded through a crowdfunding campaign at Crowd Supply.

ANAVI Macro Pad 2 Developer Kit does not require soldering. The assembly is easy, please take a look at the assembly video above for details. Although you can complete assembly with your bare hands, you might find a screwdriver and tweezers helpful.

ANAVI Macro Pad 2 Developer Kit includes a fully-soldered gold-plated green printed circuit board with two Gateron red mechanical switches, red 3 mm LEDs, an acrylic enclosure in two parts, two translucent keycaps, M2.5 screws, washers, and nuts, and awesome stickers!

To assemble ANAVI Macro Pad 2 follow these steps as shown in the video:

  • Peel off the protective films from both sides of the acrylic enclosure parts.
  • Assemble the top acrylic enclosure using two longer screws. It is not symmetric, so please pay attention to the position of capacitor C1.
  • Assemble the bottom acrylic enclosure using six nuts, three washers, and the shorter screw which is for the mounting hole between the two mechanical switches.
  • Stick the eight silicon protective pads onto the bottom: add two of them on top of each other to all four corners of the bottom acrylic plate.
  • Optionally, add stickers to the translucent keycaps.
  • Press the translucent keycaps onto the mechanical switches.

Finally, gently plug in a USB to microUSB cable and connect the ANAVI Macro Pad 2 to a personal computer. Please be careful with the microUSB connector, because harsh bending of the USB cable may damage it.

More details are available in chapter 2 of the user’s manual. As an open source project, we always welcome contributions and, if you like, you can help up improve the documentation by submitting a GitHub pull request or providing us with feedback over email. Thanks again for supporting this entirely open source project!