If you are looking for a small yet powerful IoT device you are likely to come across the
ESP8266 and compatible products on the market today. One of these the Wemos Lolin D1 Mini Pro
board strikes a remarkable balance between cost and performance. A small and very affordable
prototype board the D1 Mini Pro stands out with its WiFi functionality and a 16-Mbytes flash
memory for easy creation of a flash file system. In addition there are sufficient input and
output pins (only one analog input though) to support PWM I²C and One-Wire systems to mention
but a few. The book describes the operation modding construction and programming of home
appliances including a colorful smart home accessory a refrigerator greenhouse controller an
AC powerline monitor a door lock monitor and an IKEA Trådfri controller. As a benefit all
firmware developed for these DIY IoT-ized devices can be updated over-the-air (OTA). For most
of the designs in the book a small printed circuit board (PCB) and an enclosure are presented
so readers can have a finished and attractive-looking product. Readers having - or with access
to! - a 3D printer can print the suggested enclosures at home or in a shop. Some of the
constructions benefit from a Raspberry Pi configured as a gateway or cms server. This is also
described in detail with all the necessary configuring. You don't need to be an expert but the
prerequisites to successful replication of the projects include basic skills with PC software
including the ability to surf the Internet. In terms of hardware you should be comfortable
with soldering and generally assembling the PCBs presented in the book. All custom software
written for the IoT devices the PCB layouts and 3D print files described in the book are
available for free downloading from www.elektor.com 20370.
