ABSTRACT
In this chapter, the author's first project is a weather station that measures barometric pressure, humidity, and temperature at a number of locations inside and outside a building. He uses rrdtool to prepare plots of the measurements over periods of 4 hours, 2 days, a week, and a month. The authhor prepares database files to enable integration into an EPICS control system. He selects the NodeMCUs as microcontrollers for the sensor nodes because they are very easy to program, and flexible that they may be deployed all over the place without having to pull wires. The author shows how to connect a single sensor node, but multiple copies only differ by their IP number. As sensors, the author chooses the I2C-based sensors BMP180 for barometric pressure and HYT221 for humidity, both of which also provide temperature information.
