I have installed the Arduino IDE 2:1.0.5 on my Raspberry Pi3 under Raspbian and am using a cobbler breakout which provides a nice breadboard. On that breadboard I have installed an Arduino Nano to do analog voltage readings, which it then communicates back to the Rpi3 via the USB serial port which shows up as /dev/ttyUSB0 on the Rpi3.
This port opens as a regular file in Python for further processing such as adding a date & time stamp (obtained by an NTP server) and saving the results to a data file that is displayed in gnuplot 4.6.
You'll notice I am using 3.3 Volts for the fan to keep it quiet, and the two wires heading up to the top go to the voltage source I am monitoring. If you look closely you can see the voltage divider circuit.
Here is today's solar plant voltages which this thing tracks. The block at the bottom means the inverter was on. Green means the battery bank is full.
Anyway, it turns out that the same serial connection is supported by the Rpi Arduino IDE for programming.
Rather than programming the Nano on a laptop and constantly having to unplug/replug it on the breadboard my goal is to use Rpi Arduino IDE for programming.
So I moved all my sketches over from the Arduino IDE on the laptop to the Rpi.
.... then every time I start the Rpi IDE it throws error messages for all the sketches that have underscores in their names. Turns out the Rpi version will only allow alphanumeric directory names. I have a couple dozen sketches and this is not productive. It requires clicking OK for every directory it skips - which turns out to be all of them.
So my question is: What can I do about this?