It's easy to use the DS2484 with Python or CircuitPython, and the Adafruit_CircuitPython_DS248x module. This module allows you to easily write Python code to read 1-Wire sensors over I2C.
You can use this driver with any CircuitPython microcontroller board or with a computer that has GPIO and Python thanks to Adafruit_Blinka, our CircuitPython-for-Python compatibility library.
You'll need a DS18B20 sensor to use this example with the breakout:
CircuitPython Microcontroller Wiring
First, wire up the DS18B20 sensor to the breakout exactly as follows. Then, wire up the breakout to your board. The following is the breakout wired to a Feather RP2040 and DS18B20 sensor using the STEMMA connector and terminal block:
- Breakout terminal block GND to DS18B20 ground (blue wire)
- Breakout terminal block 1W to DS18B20 1-wire output (yellow wire)
- Breakout terminal block V+ to DS18B20 VIN (red wire)
-
Board STEMMA 3V to breakout STEMMA VIN (red wire)
-
Board STEMMA GND to breakout STEMMA GND (black wire)
-
Board STEMMA SCL to breakout STEMMA SCL (yellow wire)
- Board STEMMA SDA to breakout STEMMA SDA (blue wire)
The following is the breakout wired to a Feather RP2040 and DS18B20 using a solderless breadboard:
- Breakout GND to DS18B20 ground (blue wire)
- Breakout 1WIRE to DS18B20 1-wire output (yellow wire)
- Board 3V to DS18B20 VIN (red wire)
-
Board 3V to breakout VIN (red wire)
-
Board GND to breakout GND (black wire)
-
Board SCL to breakout SCL (yellow wire)
- Board SDA to breakout SDA (blue wire)
Python Computer Wiring
Since there are dozens of Linux computers/boards you can use, we will show wiring for Raspberry Pi. For other platforms, please visit the guide for CircuitPython on Linux to see whether your platform is supported.
Here's the Raspberry Pi wired with I2C using the STEMMA connector and terminal block for the DS18B20:
- Breakout terminal block GND to DS18B20 ground (blue wire)
- Breakout terminal block 1W to DS18B20 1-wire output (yellow wire)
- Breakout terminal block V+ to DS18B20 VIN (red wire)
-
Pi 3V to breakout STEMMA VIN (red wire)
-
Pi GND to breakout STEMMA GND (black wire)
-
Pi SCL to breakout STEMMA SCL (yellow wire)
- Pi SDA to breakout STEMMA SDA (blue wire)
Here's the Raspberry Pi wired with I2C using a solderless breadboard:
- Breakout GND to DS18B20 ground (blue wire)
- Breakout 1WIRE to DS18B20 1-wire output (yellow wire)
- Pi 3V to DS18B20 VIN (red wire)
-
Pi 3V to breakout VIN (red wire)
-
Pi GND to breakout GND (black wire)
-
Pi SCL to breakout SCL (yellow wire)
- Pi SDA to breakout SDA (blue wire)
Python Installation of DS248x Library
You'll need to install the Adafruit_Blinka library that provides the CircuitPython support in Python. This may also require enabling I2C on your platform and verifying you are running Python 3. Since each platform is a little different, and Linux changes often, please visit the CircuitPython on Linux guide to get your computer ready!
Once that's done, from your command line run the following command:
pip3 install adafruit-circuitpython-ds248x
If your default Python is version 3 you may need to run 'pip' instead. Just make sure you aren't trying to use CircuitPython on Python 2.x, it isn't supported!
CircuitPython Usage
To use with CircuitPython, you need to first install the Adafruit_CircuitPython_DS248x library, and its dependencies, into the lib folder on your CIRCUITPY drive. Then you need to update code.py with the example script.
Thankfully, we can do this in one go. 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, and copy the entire lib folder and the code.py file to your CIRCUITPY drive.
Your CIRCUITPY/lib folder should contain the following folder and file:
- adafruit_bus_device/
- adafruit_ds248x.mpy
Python Usage
Once you have the library pip3 installed on your computer, copy or download the following example to your computer, and run the following, replacing code.py with whatever you named the file:
python3 code.py
Example Code
If running CircuitPython: Once everything is saved to the CIRCUITPY drive, connect to the serial console to see the data printed out!
If running Python: The console output will appear wherever you are running Python.
# SPDX-FileCopyrightText: Copyright (c) 2024 Liz Clark for Adafruit Industries
#
# SPDX-License-Identifier: MIT
"""Adafruit DS248x DS18B20 Example"""
import time
import board
from adafruit_ds248x import Adafruit_DS248x
# Initialize I2C bus and DS248x
i2c = board.I2C()
ds248x = Adafruit_DS248x(i2c)
rom = bytearray(8)
if not ds248x.onewire_search(rom):
print("No more devices found\n\n")
print("Found device ROM: ", end="")
for byte in rom:
print(f"{byte:02X} ", end="")
print()
while True:
temperature = ds248x.ds18b20_temperature(rom)
print(f"Temperature: {temperature:.2f} °C")
time.sleep(1)
First, the DS2484 is instantiated over I2C and checks for a connected DS18B20 sensor. In the loop, the DS18B20 sensor temperature readings are printed to the serial console.
Text editor powered by tinymce.
