Cactus

🌵 An indoor WiFi-connected temperature and humidity sensor 🍶

power LiPO
wireless WiFi
sensor Humidity
mcu ESP8266
battery life 1 month
bom items 36
bom cost USD $26.92
vendors 5
completed May 2019

Downloads

Demo Code Schematic Layout ECAD KiCad files Gerber files Bill of Materials
Prototype Front
Prototype Back
Prototype Side
Prototype Top

Features













Getting Started

Step 1

Setup an IFTTT webhook to receive a POST request with data and add a row to a Google Spreadsheet.

Step 2

Access Point

Connect to the WiFi access point Cactus {UNIQUE_MAC_ADDRESS}.

Go to the web page http://cactus.local to fill in the WiFi credentials and IFTTT webhook key.

Access point

Webpage form

Step 3

Update Google Sheets with the data

Press on-board button or wait for the Google Sheet to update with a new row with a periodic update to the cloud.

Google sheets

Maintenance

⚠️ USB Connectors on WeMos D1 Mini vs WeMos battery shield

  • Do not plug in the USB cable on WeMos D1 Mini while the battery shield is on the PCB
  • Flashing firmware: Remove the battery shield from the PCB and use the USB cable on the WeMos D1 mini

Charge the LiPo by plugging in the USB cable into the battery shield