Hi @Leonid, When you connect Processing to Arduino there are lots of choices. One of the major ones is
- use the Processing Arduino library which talks to the Firmata sketch in the Arduino
- use my own Processing sketch, talking to my own Arduno sketch.
- use one of the value synchronising libraries (see Processing ref → libraries).
To avoid many of the errors I wrote an example with the intention that it works first time with data going both ways. Then you can feed your data in place of the data it uses, and then expand it with more data.