I ran into an interesting issue when trying to connect to a new printer with my Linux laptop. The printer firmware was set up for 250000 baud and for some reason I couldn’t connect to it. After a little searching, I found that this was a known issue in pyserial with newer kernels and there’s a quick fix.
When I first got started with Arduino under Linux, I quickly discovered that I had issues connecting to the Arduino to program it or talk to it via serial. I later found the same issue when I started working with 3D Printers, when trying to connect the host application to the printer to operate it.
This was clearly a permissions problem, as all of these cases (and other USB serial devices) worked just fine when run as root (not a good practice, don’t do this). This is just a quick post showing how to set yourself up with the permissions needed to use these devices as a normal user.