But wait! There's more -- the Circuit Playground Express can also tell the temperature!
How, you ask? With a build in thermistor. This little sensor is a thermally sensitive resistor, meaning it's resistance changes based on temperature.
We can access its readings in CircuitPython by importing the adafruit_thermistor library, and then using the board.TEMPERATURE
pin to read the thermistor value.
In the example below, click the Download Project Bundle button below to download the necessary libraries and the code.py file in a zip file. Extract the contents of the zip file, open the directory and then click on the directory that matches the version of CircuitPython you're using and copy the contents of that directory to your CIRCUITPY drive.
Your CIRCUITPY drive should now look similar to the following image:

# SPDX-FileCopyrightText: 2017 John Edgar Park for Adafruit Industries # # SPDX-License-Identifier: MIT # Circuit Playground Temperature # Reads the on-board temperature sensor and prints the value import time import adafruit_thermistor import board thermistor = adafruit_thermistor.Thermistor( board.TEMPERATURE, 10000, 10000, 25, 3950) while True: temp_c = thermistor.temperature temp_f = thermistor.temperature * 9 / 5 + 32 print("Temperature is: %f C and %f F" % (temp_c, temp_f)) time.sleep(0.25)
Then, open up a REPL session and you'll see the temperature readings in both Celsius and Fahrenheit.Â
Try placing your finger over the sensor (you'll see a thermometer icon on the board) and watch the readings change.
Page last edited January 22, 2025
Text editor powered by tinymce.