is there an issue with USB-serial converter support?

[Robert L Cochran]

I do not have a problem with FTDI-based UARTs like the FT232R devices.
I've been merrily programming Arduino devices on F11 using the FTDI
uarts. I think the PL2303 you have is also known as the Dynex
USB-to-Serial converter, and I have one of those. I'll give it a try
tomorrow.

It could be that the PL2303 need a kernel config turned on. But when
I've used (what I think are) equivalent devices in the past, they have
always worked great in Fedora kernels.

Please note that my username belongs to all of these groups:

uucp
dialout <--- this one is important in F11 for /dev/ttyUSBn
lock
wheel

I was getting nastygrams from Arduino's IDE until I updated my group
memberships.

Bob


Robert P. J. Day wrote:
>   here's what's happening.  f11 x86_64 updated beta, connected to an
> embedded (beagleboard) system thusly:
>
>   host USB port <->
>     regular USB cable <->
>       targus port replicator with serial port <->
>         null modem cable <->
>           everex PC AT cable (DB9 to 10-pin connector)
>
> works fine -- minicom at 115200 8N1, no flow control, and device file
> /dev/ttyUSB0.  when i plug it in, my host /var/log/messages appears
> thusly:
>
> ay  8 19:47:19 localhost kernel: usb 2-1.4: new full speed USB device
> using ohci_hcd and address 74
> May  8 19:47:19 localhost kernel: usb 2-1.4: New USB device found,
> idVendor=0711, idProduct=0230
> May  8 19:47:19 localhost kernel: usb 2-1.4: New USB device strings:
> Mfr=1, Product=2, SerialNumber=3
> May  8 19:47:19 localhost kernel: usb 2-1.4: Manufacturer: USB-RS232
> Interface Converter
> May  8 19:47:19 localhost kernel: usb 2-1.4: SerialNumber: 204395
> May  8 19:47:19 localhost kernel: usb 2-1.4: configuration #1 chosen
> from 1 choice
> May  8 19:47:19 localhost kernel: mct_u232 2-1.4:1.0: MCT U232
> converter detected
> May  8 19:47:19 localhost kernel: usb 2-1.4: MCT U232 converter now
> attached to ttyUSB0
> May  8 19:47:19 localhost NetworkManager: <info>  (ttyUSB0): ignoring
> due to lack of mobile broadband capabilties
>
> looks good, and i'm connected to the console on the beagle board.
>
>   what i want to do now is replace the clunky targus port replicator
> with a USB-serial converter to give me:
>
>   host USB port <->
>     no-name USB-serial converter cable <->
>       null modem cable <->
>         everex PC AT cable (DB9 to 10-pin connector)
>
> but i've yet to get that to work properly.  when i plug in the
> converter, i get:
>
> May  8 19:57:21 localhost kernel: usb 2-1: new full speed USB device
> using ohci_hcd and address 78
> May  8 19:57:22 localhost kernel: usb 2-1: New USB device found,
> idVendor=067b, idProduct=2303
> May  8 19:57:22 localhost kernel: usb 2-1: New USB device strings:
> Mfr=1, Product=2, SerialNumber=0
> May  8 19:57:22 localhost kernel: usb 2-1: Product: USB-Serial
> Controller
> May  8 19:57:22 localhost kernel: usb 2-1: Manufacturer: Prolific
> Technology Inc.
> May  8 19:57:22 localhost kernel: usb 2-1: configuration #1 chosen
> from 1 choice
> May  8 19:57:22 localhost kernel: pl2303 2-1:1.0: pl2303 converter
> detected
> May  8 19:57:22 localhost kernel: usb 2-1: pl2303 converter now
> attached to ttyUSB0
> May  8 19:57:22 localhost NetworkManager: <info>  (ttyUSB0): ignoring
> due to lack of mobile broadband capabilties
>
>   except that what i see in minicom is crap -- lots of unprintable
> characters, as if it's running at the wrong baud rate or something.  i
> didn't do anything special when i plugged in the converter, and here's
> the first few lines from "modinfo pl2303":
>
> filename:
> /lib/modules/2.6.29.2-129.fc11.x86_64/kernel/drivers/usb/serial/pl2303.ko
> license:        GPL
> description:    Prolific PL2303 USB to serial adaptor driver
> srcversion:     EF203DC966F54AFA826B33F
> ...
>
>   is there a known issue with USB-serial converters?  i just noticed
> that that module has a single load-time parameter:
>
> debug:Debug enabled or not (bool)
>
> so i guess i can try that next and see what happens.  but i was
> expecting this to work right out of the box, as they say.
>
> rday
> --
>
> ========================================================================
> Robert P. J. Day                               Waterloo, Ontario, CANADA
>
>         Linux Consulting, Training and Annoying Kernel Pedantry.
>
> Web page:                                          http://crashcourse.ca
> Linked In:                             http://www.linkedin.com/in/rpjday
> Twitter:                                       http://twitter.com/rpjday
> ========================================================================
>
>