Flash Magic error: "Unable to communicate.(in use)Ensure no other applications are using the COM Port. Try raising or lowering the baud rate"

Question

I am trying to burn a .hex file on LPC2129 by connecting it through USB wire with my PC by using Flash Magic software on Ubuntu 20.04. The moment I press start on Flash Magic it shows the error below:

Unable to communicate.(in use)Ensure no other applications are using the COM Port. Try raising or lowering the baud rate.

I have tried many options like:

ln -s /dev/ttyUSB0 ~/.wine/dosdevices/com3 (or any other com port), earlier it was not creating a symbolic link and was throwing an error: ln: failed to create symbolic link '/home/lakshya/.wine/dosdevices/com3': File exists.

But when I used ln -sf /dev/ttyUSB0 ~/.wine/dosdevices/com3, it did not throw any error and executed it.

But again when I pressed the start button on Flash Magic it gave same error: Unable to communicate.(in use)Ensure no other applications are using the COM Port. Try raising or lowering the baud rate.

I have performed steps mentioned in the link below but it did not resolve: Flash Magic on Ubuntu

Please find the images below too for understanding the query:

Question: Is your userid in the same group as /dev/ttyUSB0? id;stat --format="%G" /dev/ttyUSB0?

Answer: By using the commands below:

command1-> id

Output - id=1000(lakshya) gid=1000(lakshya) groups=1000(lakshya),4(adm),24(cdrom),27(sudo),30(dip),46(plugdev),120(lpadmin),131(lxd),132(sambashare)

command2-> stat --format="%G" /dev/ttyUSB0

Output - dialout

Answer 1

You need to add your userid to the dialout group. An ls -l /dev/ttyUSB0 will show that group members have rw- access.

Read man adduser, and do

sudo adduser $USER dialout

Once that is done, either use newgrp dialout (Read man newgrp) to create a process with the new group, or logout and login again to endow all your processes with the new group.