Okay so lsusb gives Bus 002 Device 019: ID 1a86:7523 QinHeng Electronics HL-340 USB-Serial adapter
dmesg|grep 'ttyUSB' gives
[63723.589107] usb 2-1: ch341-uart converter now attached to ttyUSB0
but tty lists only /dev/pts/0 although in /dev there is a ttyUSB0 file (or whatever it is because vim says its not a file)
I can use cu -l /dev/ttyUSB0 -s 9600 and transmit to arduino nano as the rx LED blinks. On starting arduino I get the "java.lang.NullPointerException thrown while loading gnu.io.RXTXCommDriver" error.
System: Linux Mint 19.1 Tessa (64 bit)