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b-parasite firmware build


PCB front and back photo

b-parasite is an open source soil moisture and ambient temperature/humidity/light sensor.



This repository also hosts a few different firmware samples for b-parasite.

Sample Description Extra Documentation
samples/ble This is the most battle-tested and useful firmware. It periodically reads all sensors and broadcast them via Bluetooth Low Energy (BLE). It works with Home Assistant + BTHome out of the box. Docs
samples/zigbee An experimental/educational/exploratory basic Zigbee sample built on nRF Connect + ZBOSS. It integrates with Home Assistant via ZHA or Zigbee2MQTT. Docs
samples/blinky The classic "Hello, world" -
samples/soil_read_loop Reads the soil moisture sensor on a loop. Useful for experimenting and calibrating the sensor. -
samples/input Handles button presses. Useful for power profiling GPIO interrupts and testing debouncing for push switches on boards that have them. -


Information about how to order, assemble, build the samples, protect the sensor and flash the firmware is on the Wiki.

Repository Organization

b-parasite stuck into a small plant vase


Render of the original 3D printable case

We have three different 3D-printable cases:

  1. Original snap-on case - case/Top.stl, case/Bottom.stl
  2. High airflow - case/b_parasite_case_high_airflow.stl
  3. Mushroom-style - available on Printables


The hardware and associated design files are released under the Creative Commons CC BY-SA 4.0 license. The code is released under the MIT license.