I need to read a few sensors:
DHT22 temperature-humidity sensor
Adafruit TSL2591 High Dynamic Range Digital Light Sensor
MiniPH I2C Interface MinipH I2C pH Interface - Sparky's Widgets
But my Arduino Nano is already reaching max. sketchsize with just loading the lib for the DHT22.
If I understand it right, I don't need to use the libraries if I just want single functions, like a data-read?
I having a hard time how to query all sensors like every 2-3secs and store the data in RAM until all is send over the UART to a RasperryPi3. This raises another question: what should I use to transmit the data over 30-50m of telephone-cable or Cat5-STP? Does plain UART work good enough or is there any lightweight protocol with a bit of errorcorrection?