Temperature measurement – DS1820
After some research about how to easaly measure the temperatures in an office-building, and cheap ofcourse, i discovered on internet some small projects with the Dallas 1820 chip. 3 wires, only 2 needed when parasite powered, and they can easaly be connected to a bus-network!!! And they only cost about 7 euro each. And if you want them for free? you can get some samples at Maxim.
In the links below you can find some information about an interface between the sensors and your PC’s serial port. And you can write your own software because drivers of iButton are also for free. I started to modify an example i found in Delphi.