What Are We Here For?

To improve our sensing of our environment

Build your own temp/humidity sensor!

  • In reality we're integrating:
    • 3 sources of temperature
    • 2 sources of humidity
    • 1 source of barometric pressure
  • AND we might as well calculate and collect dew point, relative humidity and altitude while we're at it

Home Assistant

  • Those of you that know me - I'm hooked
  • Many ways to collect data, this is my favorite
  • We'll talk about other options as well

Leveraging ESPHome

  • Provides framework for utilizing ESP-based devices
  • Handles OTA upgrades
  • Standardizes configs
  • Teaches you to either love or hate YAML

ESP32 Dev Board

  • Too many wonderful features
  • We're using Wifi, BLE and i2c
  • Via ESPHome


  • I2CI^2C (Inter-Integrated Circuit, eye-squared-C), alternatively known as I2C or IIC, is a synchronous, multi-controller/multi-target (controller/target), packet switched, single-ended, serial communication bus invented in 1982 by Philips Semiconductors. It is widely used for attaching lower-speed peripheral ICs to processors and microcontrollers in short-distance, intra-board communication. (Wikipedia)


  • Temperature and Humidity
  • A variant of this sensor is within the BLE sensor as well
  • via i2c


  • Temperature and Pressure
  • We wanted the BME280 for temperature, humidity and pressure but prices are too high
  • also i2c


  • Bluetooth Low Energy (Bluetooth LE, colloquially BLE, formerly marketed as Bluetooth Smart[1]) is a wireless personal area network technology designed and marketed by the Bluetooth Special Interest Group (Bluetooth SIG)[2] aimed at novel applications in the healthcare, fitness, beacons,[3] security, and home entertainment industries.[4]

BLE Sensor


  • Not the exact components but highlights the attention needed for differences in pinouts.


ESPHome Configuration

Helpful Juniper Technologies Links

Juniper Dashboard

Juniper Garden Mobile App

Why Collect Data Like This?

  • Weather Stations
  • Place BLE Sensors Everywhere - they're cheap
  • Augment understanding of home climate control
  • Monitor Freezer, Fridge, Clothes Dryer
  • Get creative! Trash Can Location

It's been over 2 years since we last met in person, indoors at an official venue - and we heard about a project MQTT, Grafana, Arduino nad IoT data acquisition. Interestingly we'll be covering aspects of each of those again today Curious -- who is with us for the first time? Introductions

But first - Thank you to Techlahoma for continued sponsorship!

You saw this picture on the meetup. Like many projects there is trial and error. I was inspired to test some of my connections with a display I knew that worked, verifying my I2C was working. It also served a good welcome

The title of the meetup was a bit misleading, we're actually building a bit more than a temp/humidity sensor

Show of hands, how many of you in this room have heard of Home Assistant? How many are running HA? How many are fed up with HA?

The object in the background is a picture of my esp32 that sits within the entertainment center, collecting from 12 different BLE sensors including temperature indoors, outdoors, in freezers, in fridges, in the dryer, outsdide, at my trash can for location tracking, humidity, soil moisture