Serial Input in Ubuntu, Usb to serial converter (Pl2303 – Prolific) not working in ubuntu 18.04

I am trying to read input from a Electronic weighing scale (Weigh sensor) connected to Ubuntu enabled UDOO board using a Prolific PL2303 serial converter cable (CA-US9), but am unable to read any input from the sensor. To monitor the input I have tried using (Coolterm & GTKTerm), assuming an issue with the driver I have referred and tried updating the DTR line as the solutions suggested in the following stack overflow resources Reference 1,Reference 2,Reference 3.

I have tied the same on the ubuntu based computer too but the issue remain the same. Using the dmesg command i was able to check that the device has been detected properly when connected. The output to the command executed as dmesg | tail is as follows :

[ 7365.393110] usb 1-3: new full-speed USB device number 53 using xhci_hcd
[ 7365.542407] usb 1-3: New USB device found, idVendor=067b, idProduct=2303, bcdDevice= 4.00
[ 7365.542424] usb 1-3: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[ 7365.542437] usb 1-3: Product: USB-Serial Controller D
[ 7365.542448] usb 1-3: Manufacturer: Prolific Technology Inc. 
[ 7365.545546] pl2303 1-3:1.0: pl2303 converter detected
[ 7365.552313] usb 1-3: pl2303 converter now attached to ttyUSB0
[ 7373.296214] usb 1-3: USB disconnect, device number 53
[ 7373.297492] pl2303 ttyUSB0: pl2303 converter now disconnected from ttyUSB0
[ 7373.297644] pl2303 1-3:1.0: device disconnected

The device remains connected physically but seems disconnected by the command output, Also please suggest how to find the port id for the serial port connected.

Answer

Need to set the permissions for /dev/ttyUSB0. If user dialout is cumbersome, then we have to grant universal permissions to /dev/ttyUSB0. Command is “sudo chmod 666 /dev/ttyUSB0”