I'm having the same problem as you but in a different context ( I open a serial console on a linux box ). The serial link sometimes becomes unresponsive and I have to physically unplug the USB-serial converter. The below seems to solve my problem, but not always. • Find the driver associated to your ttyUSBx device.
[my-pc]# cat /proc/tty/drivers /dev/tty /dev/tty 5 0 system:/dev/tty /dev/console /dev/console 5 1 system:console /dev/ptmx /dev/ptmx 5 2 system /dev/vc/0 /dev/vc/0 4 0 system:vtmaster rfcomm /dev/rfcomm 216 0-255 serial usbserial /dev/ttyUSB 188 0-253 serial ttyprintk /dev/ttyprintk 5 3 console serial /dev/ttyS 4 64-111 serial pty_slave /dev/pts 136 0-1048575 pty:slave pty_master /dev/ptm 128 0-1048575 pty:master unknown /dev/tty 4 1-63 console You can see that /dev/ttyUSB uses usbserial. Now dig a little further: [my-pc]# lsmod grep usbserial usbserial 37173 1 pl2303 In my case, my USB-to-serial converter is a Prolific PL2303. If you have a FTDI adapter, I think you should see ftdi_sio instead of pl2303. • Unload the driver sudo modprobe -r pl2303 #or the name that matches your config sudo modprobe -r usbserial • Re-load the driver sudo modprobe pl2303 #or the name that matches your config • Re-launch your serial communication. 
With sdive's answer I kept getting 'FATAL: Module usbserial is in use.' Here is my answer for the module ftdi_sio. Steps are adapted from the above answer and the link from a comment in the original question. Crossword forge 7 3 keygen crack.
I could not get the module to be removed:% sudo rmmod ftdi_sio rmmod: ERROR: Module ftdi_sio is in use% sudo modprobe -r ftdi_sio modprobe: FATAL: Module ftdi_sio is in use.
Most of case, PL2303 driver is installed and apply to below command to verify it.
Continue reading 'How to enable USB-Serial Port adapter (RS-232) in Ubuntu Linux' Skip to content. Mypapit gnu/linux. Free and Open Source blogger with an attitude. Posted on May 12, 2008 January 15, 2018 by mypapit. I need driver of this serial port converter. Tweezak says. Aug 1, 2018 - I found an old manual which explained 'commonly communication cables use only 3 pins (RXD, TXD, and GND). This device has a hardware.