ezflyer made a RS-485 network temperature sensor: [via]
This design will be used as part of my home automation system to measure temperatures in various parts of the house. I already have the wiring in place for an extensive RS-485 network, so the installation of the individual sensors will be easy. I’m currently working on a wireless version for my hot tub, and for an unattached workshop/garage.
This design is based on the PIC 16F648A processor, the MAX485 RS-485 interface IC, and the TC77 integrated temp. sensor. Each board has a (software) programmable network address, and network biasing (if required).
RS-485 network temperature sensor – [Link]