From George Smart's Wiki
One of my interests which probably comes across on this site is data. I like to collect and analyse data. I like to see what I can learn from numbers. This page isn't really about learning anything, but it's a nice source of data.
This page uses an Arduino based temperature gathering system, detailed below, to talk to a Dallas/Maxim DS18B20-par 1-Wire Digital Thermometer. The Arduino then relays the temperature data to the PC where The data is collected in a round robin database and plotted (see RRDTool's website).
The idea was based on an idea David Mills had for doing this on the Raspberry Pi. I shamelessly stole his idea, screwed around with his code and improved it (I like to think!).
Recording started on the 10th January 2013. Any gaps in the graph are probably caused by my amateur radio hobby.
Minimum and Maximum temperatures recorded since start of measurement, as well as the current temperature, accurate to within 10 seconds.
The DS18B20-par is parasite powered, meaning it takes power from the bus. For this reason, a 4.7KΩ resistor is used to supply power. There is one active bus wire and one ground wire to the DS18B20 sensor. The DS18S20 is a lower resolution device. It is connected up as follows:
Image borrowed from here, which describes the connection process in a bit more detail.
The sensor is located close to the ground in a well shaded but breezy location which is ideal.