At the junction of I.T. & homesteading

I started acquiring multiple Raspberry Pi Zeros for the purpose of starting to figure out a consistent deployment scheme for the various automation related projects I envision for our homestead.

For now I’ve simply deployed 2 DS18b20 temperature sensors. One on the existing Pi in the Solar shed which serves this blog, and another on a Pi Zero in the house. Only sensing for now which complements the data I’m gathering from the solar array.

The Pi Zero consumes between 0.1 and 0.2 AmpsIMG_7476

Sample data being gatheredScreen Shot 2016-12-10 at 10.25.03 PM

Here are my current install notes for the Pi Zero.

To limit power consumption, add this to /etc/rc.local to turn off HDMI output

/usr/bin/tvservice -o

To be able to read from the temperature probe, add the following line to /boot/config.txt

dtoverlay=w1-gpio:3

Get the python-w1thermsensor package

sudo apt-get install python-w1thermsensor

Reboot & make sure devices are listed in /sys/bus/w1/devices

The python code necessary to read the probe is:

from w1thermsensor import W1ThermSensor
# assuming only 1 sensor
sensor = W1ThermSensor.get_available_sensors( [W1ThermSensor.THERM_SENSOR_DS18B20] )[0]
temperature = sensor.get_temperature()
if temperature is not None:
    print '%.1f' % (temperature)
else:
    print "failed to get reading."

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