Currently I am working on a project that will take temperature, humidity, and pressure readings from 8 sensors (BME680 sensors) and relay them back to an Arduino Uno Rev 3 board. I would like to somehow connect these sensors so that the data can be accessed remotely. The sensors are connected to ethernet cables rather than jumper wires and I was wondering how I should connect these ethernet cables to an Arduino board in order to use the sensors. The last problem I was running into was regarding the fact that there are 8 sensors. What is the best option to interface all 8 into one Arduino board? Any ideas on how to make this data remotely accessible?
A BME680 sensor can be read by SPI or I2C. Both bus systems are designed to be used on a PCB, both buses have maximal lengths of about 50cm (in total). I assume that you expect much longer bus lengths as you plan to use ethernet cables. For an I2C bus this can be achieved by using a bus multiplexer together with a bus expander. That means at lot of additional circuitry (17 chips) which adds a lot of complexity to your project. I would suggest to use some ESP boards to read the sensor data and send it to a central node that collects all (and do whatever you planned to do with the information).