I found it awkward getting started with the BV4626 from the information available and offer the following suggestions. In my simple case of only one ttyUSB it is simple to confirm what the device is known as by doing ls /dev/ttyUSB* which will return the actual dev number, probably /dev/ttyUSB0. If the is more than one device listed then this simple guide is not for you. Given the device numby WilliamN - Projects