Preamble
This article, the 11th in a series on home automation documents how to create and integrate an IoT Desktop Device into an existing home automation system including all the necessary software functionality to enable the successful deployment within a domestic environment.
Picture 1 shows the completed IoT desktop device and Picture 2 shows all the component parts used in the prototype which were ‘shoe horned’ into the finished article.
Introduction
As mentioned above this Instructable details how to make an IoT Desktop Device whose primary purpose is to present the user with an ‘at a glance’ summary of temperature and humidity levels published by distributed sensors within an IoT network accompanied by local barometric pressure along with time and date.
The design seamlessly hooks into the MQTT/OpenHAB based IoT network detailed in this series on home automation (HA), building on reused code taken from here. Alternatively as the MQTT interface is fully documented throughout it can be simply be adapted to an existing HA system via MQTT publications/subscriptions.
At it’s heart is an ESP8266-12E which is responsible for MQTT communications and controlling all functionality excepting LCD display back-lighting control and gesture sensing which use an ATTiny85 and ATMega328P respectively. The device is fully configurable via text files stored on a local SD card, though calibration and network security parameters can also be programmed via remote MQTT publications.”

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