Timofurrer/w1thermsensor - Docker Image

⁠W1ThermSensor

Get the temperature from your w1 therm sensor in a single line of code! It's designed to be used with the Rasperry Pi hardware but also works on a Beagle Bone and others.

New: use w1thermsensor as a CLI tool⁠! - Since version 0.3.0

Raspberry Pi: this package is available in Rasbian as python-w1thermsensor and python3-w1thermsensor.

⁠Supported devices

The following w1 therm sensor devices are supported:

• DS18S20
• DS1822
• DS18B20
• DS28EA00
• DS1825/MAX31850K

⁠Setup

You just need a w1 therm sensor. Some of them can be bought here: Adafruit: DS18B20⁠ I've used a Raspberry Pi with an GPIO Breakout (Pi Cobbler). Other hardware like the Beagle Bone are supported, too.

⁠Installation

⁠From PIP

This possibility is supported on all distribution:

pip install w1thermsensor Copy

Note: maybe root privileges are required

⁠On Raspbian using apt-get

If you are using the w1thermsensor module on a Rasperry Pi running raspbian you can install it from the offical repository:

sudo apt-get install python-w1thermsensor Copy

Or if you are using python 3:

sudo apt-get install python3-w1thermsensor Copy

⁠Create debian packages

debuild -us -uc Copy

⁠Usage as python package

The usage is very simple and the interface clean.. All examples are with the DS18B20 sensor - It works the same way for the other supported devices.

⁠Basic usage with one sensor (implicit)

from w1thermsensor import W1ThermSensor sensor = W1ThermSensor() temperature_in_celsius = sensor.get_temperature() temperature_in_fahrenheit = sensor.get_temperature(W1ThermSensor.DEGREES_F) temperature_in_all_units = sensor.get_temperatures([ W1ThermSensor.DEGREES_C, W1ThermSensor.DEGREES_F, W1ThermSensor.KELVIN]) Copy

The need kernel modules will be automatically loaded in the constructor of the W1ThermSensor class. If something went wrong an exception is raised.

The first found sensor will be taken

⁠Basic usage with one sensor (explicit)

The DS18B20 sensor with the ID 00000588806a will be taken.

from w1thermsensor import W1ThermSensor sensor = W1ThermSensor(W1ThermSensor.THERM_SENSOR_DS18B20, "00000588806a") temperature_in_celsius = sensor.get_temperature() Copy

⁠Multiple sensors

With the get_available_sensors class-method you can get the ids of all available sensors.

from w1thermsensor import W1ThermSensor for sensor in W1ThermSensor.get_available_sensors(): print("Sensor %s has temperature %.2f" % (sensor.id, sensor.get_temperature())) Copy

Only sensors of a specific therm sensor type:

from w1thermsensor import W1ThermSensor for sensor in W1ThermSensor.get_available_sensors([W1ThermSensor.THERM_SENSOR_DS18B20]): print("Sensor %s has temperature %.2f" % (sensor.id, sensor.get_temperature())) Copy

⁠Set sensor precision

Some w1 therm sensors support changing the precision for the temperature reads. w1thermsensor enables to do so with the W1ThermSensor.set_precision() method:

sensor = W1ThermSensor(W1ThermSensor.THERM_SENSOR_DS18B20, "00000588806a") sensor.set_precision(5) Copy

If the persist argument is set to False this value is "only" stored in the volatile SRAM, so it is reset when the sensor gets power-cycled.

If the persist argument is set to True the current set precision is stored into the EEPROM. Since the EEPROM has a limited amount of writes (>50k), this command should be used wisely.

sensor = W1ThermSensor(W1ThermSensor.THERM_SENSOR_DS18B20, "00000588806a") sensor.set_precision(5, persist=True) Copy

Note: this is supported since Linux Kernel 4.7

⁠Disable kernel module auto loading

Upon import of the w1thermsensor package the w1-therm and w1-gpio kernel modules get loaded automatically. This requires the python process to run as root. Sometimes that's not what you want, thus you can disable the auto loading and load the kernel module yourself prior to talk to your sensors with w1thermsensor.

You can disable the auto loading feature by setting the W1THERMSENSOR_NO_KERNEL_MODULE environment variable to 1:

# set it globally for your shell so that sub-processes will inherit it. export W1THERMSENSOR_NO_KERNEL_MODULE=1 # set it just for your Python process W1THERMSENSOR_NO_KERNEL_MODULE=1 python my_awesome_thermsensor_script.py Copy

Every other values assigned to W1THERMSENSOR_NO_KERNEL_MODULE will case w1thermsensor to load the kernel modules.

Note: the examples above also apply for the CLI tool usage. See below.

⁠Usage as CLI tool

The w1thermsensor module can be used as CLI tool since version 0.3.0. Please note that the CLI tool will only get installed with the Raspbian Python 3 package (sudo apt-get install python3-w1thermsensor)

⁠List sensors

List all available sensors:

$ w1thermsensor ls $ w1thermsensor ls --json # show results in JSON format Copy

List only sensors of a specific type:

$ w1thermsensor ls --type DS1822 $ w1thermsensor ls --type DS1822 --type MAX31850K # specify multiple sensor types $ w1thermsensor ls --type DS1822 --json # show results in JSON format Copy

⁠Show temperatures

Show temperature of all available sensors: (Same synopsis as ls)

$ w1thermsensor all --type DS1822 $ w1thermsensor all --type DS1822 --type MAX31850K # specify multiple sensor types $ w1thermsensor all --type DS1822 --json # show results in JSON format Copy

Show temperature of a single sensor:

$ w1thermsensor get 1 # 1 is the id obtained by the ls command $ w1thermsensor get --hwid 00000588806a --type DS18B20 $ w1thermsensor get 1 # show results in JSON format Copy

Show temperature of a single sensor in the given precision

$ w1thermsensor get 1 --precision 10 $ w1thermsensor get --hwid 00000588806a --type DS18B20 --precision 11 Copy

⁠Change temperature read precision and write to EEPROM

$ w1thermsensor precision 1 10 $ w1thermsensor precision --hwid 00000588806a --type DS18B20 11 Copy

⁠Contribution

I'm happy about all types of contributions to this project! :beers:

This project is published under MIT⁠.A Timo Furrer⁠ project.- :tada: -