How do I connect to a terminal to a serial-to-USB device on Ubuntu 10.10 (Maverick Meerkat)? - linux

Question

I am trying to connect minicom to a serial device that is connected via a USB-to-serial adapter. This is a PL2303 and from everything I've read no additional drivers are required. The device is recognised as a PL2303.
I'm a beginner at minicom. Is this the correct command to execute? Or do I need to configure something?
$ sudo minicom --device /dev/ttyUSB0
minicom: cannot open /dev/ttyUSB0: No such file or directory
$ sudo lsusb -v
Bus 002 Device 006: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port
Device Descriptor:
bLength 18
bDescriptorType 1
$ tail /var/log/syslog #then removed and attached the device.
Mar 13 23:31:49 ubuntu kernel: [807996.786805] usb 2-1: pl2303 converter now attached to ttyUSB0
Mar 13 23:34:44 ubuntu kernel: [808172.155129] usb 2-1: USB disconnect, address 7
Mar 13 23:34:44 ubuntu kernel: [808172.156321] pl2303 ttyUSB0: pl2303 converter now disconnected from ttyUSB0
Mar 13 23:34:44 ubuntu kernel: [808172.156374] pl2303 2-1:1.0: device disconnected
Mar 13 23:34:52 ubuntu kernel: [808179.497856] usb 2-1: new full speed USB device using uhci_hcd and address 8
Mar 13 23:34:52 ubuntu kernel: [808179.785845] pl2303 2-1:1.0: pl2303 converter detected
Mar 13 23:34:52 ubuntu kernel: [808179.872309] usb 2-1: pl2303 converter now attached to ttyUSB0

Answer 1

First check with dmesg | grep tty if system recognize your adapter.
Then try to run minicom with sudo minicom -s, go to "Serial port setup" and change the first line to /dev/ttyUSB0.
Don't forget to save config as default with "Save setup as dfl". It works for me on Ubuntu 11.04 on VirtualBox.

Answer 2

You will need to set the permissions every time you plug the converter in.
I use PuTTY to connect. In order to do so, I have created a little Bash script to sort out the permissions and launch PuTTY:
#!/bin/bash
sudo chmod 666 /dev/ttyUSB0
putty
P.S. I would never recommend that permissions are set to 777.

Answer 3

Long time reader, first time helper ;)
I'm going through the same hellish experience here with a Prolific USB <> Serial adapter and so far Linux is the easiest to get it to work.
On CentOS, I didn't need to install any drivers etc.. That said,
dmesg | grep -i tty or dmesg | grep -i usb showed me /dev/ttyUSB0.
screen ttyUSB0 9600 didn't do the trick for me like it did in OSX
minicom is new to me but it was complaining about lack of /dev/modem
However, this helped: https://www.centos.org/forums/viewtopic.php?t=21271
So install minicom (yum install minicom) then enter its settings (minicom -s).
Then select Serial Port Setup and change the Serial Device (Option A) to /dev/ttyUSB0, or whatever your device file is as it slightly differs per distro.
Then change the Bps (Option E) to 9600 and the rest should be default (8N1 Y N)
Save as default, then simply minicom and Bob's your uncle.
HTH.

Answer 4

The serial port communication programs moserial or gtkterm provide an easy way to check connectivity and modify /dev/ttyUSB0 (or /dev/ttyUSB1!) settings. Even though there maybe only a single USB to RS232 adapter, the n designation /dev/ttyUSBn can and does change periodically! Both moserial and gtkterm will show what port designation is relevant in their respective pull down menus when selecting an appropriate port to use.
Check out help.ubuntu.com/community/Minicom for details on minicom.

Answer 5

I had fix this with adduser *username* dialout. I never had this error again, even though previously the only way to get it to work was to reboot the PC or unplug and replug the usb to serial adapter.

Answer 6

I get get the same minicom error, "cannot open /dev/ttyUSB0: No such file or directory"
Three notes:
I get the error when the device attached to the serial port end of my Prolific Technology PL2303 USB/Serial adapter is turned off. After turning on the device (an embedded controller running Linux) minicom connected fine.
I have to run as super user (i.e. sudo minicom)
Sometimes I have to unplug and plug back in the USB-to-serial adapter to get minicom to connect to it.
I am running Ubuntu 10.04 LTS (Lucid Lynx) under VMware (running on Windows 7). In this situation, make sure the device is attached to VM operating system by right clicking on the USB/Serial USB icon in the lower right of the VMware window and select Connect (Disconnect from Host).
Remember to press Ctrl + A to get minicom's prompt, and type X to exit the program. Just exiting the terminal session running minicom will leave the process running.

Answer 7

I had the exact same problem, and it was fixed by doing a chmod 777 /dev/ttyUSB0. I never had this error again, even though previously the only way to get it to work was to reboot the VM or unplug and replug the USB-to-serial adapter. I am running Ubuntu 10.04 (Lucid Lynx) VM on OS X.

Answer 8

I suggest that newbies connect a PL2303 to Ubuntu, chmod 777 /dev/ttyUSB0 (file-permissions) and connect to a CuteCom serial terminal. The CuteCom UI is simple \ intuitive. If the PL2303 is continuously broadcasting data, then Cutecom will display data in hex format

Answer 9

I just got my GUC232A cable with a molded-in PL2302 converter chip.
In addition to adding myself and br to group dialout, I found this helpful tip in the README.Debian file in /usr/share/doc/bottlerocket:
This package uses debconf to configure the /dev/firecracker symlink,
should you need to change the symlink in the future run this command:
dpkg-reconfigure -pmedium bottlerocket
That will then prompt you for your new serial port and modify the
symlink. This is required for proper use of bottlerocket.
I did that and voila! bottlerocket is able to communicate with my X-10
devices.

Answer 10

Putty on ubuntu
There is no need to install the driver for PL2303
So only type the command to enable the putty
Sudo chmod 666 /dev/ttyUSB0
Done
Open the putty.