SOLVED USB Serial Com Initialization

[Ken Kloster]

07/14/18

Recently I installed Arduino's IDE and could not get it to open the USB port.
I uninstalled "Brltty" com port driver per instructions found in this forum. See Below:
sudo apt -get remove brltty

If you run this routine through the terminal, you can verify your serial ports. This will all list USBs devises attached ie. /dev/ttyUSB0.
ls/dev/ttyUSB*

If you run this routine through the terminal, you will see what serial ports exist and what drivers are being used.
dmesg | tail

Still the Arduino IDE could not open the USB port (/dev/USB0).

Since I needed a simple modem program for hardware/software development use anyway, I went to the Digi website and downloaded and installed their modem program for Linux. After installation, I found that the X-CTU program could not open the USB port either. The X-CTU did however give me a hint. The reason I could not open the port was that I did not have permission to open the port. In researching the problem on the Digi site (www.digi.com/xctu), I found out that Linux will not allow anybody access its com ports unless they have been given permission.

Below is how you get permission:
1, Open a terminal console.
2, Execute the following command where <user> is the user you want to add to the dialout
group: sudo usermod -a -G dialout <user>
3, Log out and log in again with your user.

After doing that, the X-CTU program worked!!

When I loaded the Arduino IDE, I found that it also works.

Hope this little note helps someone.

Ken

[BDW]

It certainly did help me.
I had a problem connecting a "cheap" arduino board, equipped with a CH340 USB to serial chip.
After reading your post and following the instructions it works like a charm.

Thank you Ken.