can i use a simple USB-serial converter to connect to console?

rather than mess around with a full-blown port replicator to connect
to the console on my BB, i picked up a simple USB-serial converter and
am trying to use that to go from USB on my laptop to the serial port
at the other end, then a gender changer, and finally to the serial
(AT/Everex workalike) cable.

  here's the converter cable:

http://www.prolific.com.tw/eng/Products.asp?ID=59

and when i plug it into my fedora 9 system, i see this in
/var/log/messages;

Mar 14 18:18:44 localhost kernel: usb 2-1: new full speed USB device using uhci_hcd and address 69
Mar 14 18:18:45 localhost kernel: usb 2-1: configuration #1 chosen from 1 choice
Mar 14 18:18:45 localhost kernel: pl2303 2-1:1.0: pl2303 converter detected
Mar 14 18:18:45 localhost kernel: usb 2-1: pl2303 converter now attached to ttyUSB0
Mar 14 18:18:45 localhost kernel: usb 2-1: New USB device found, idVendor=067b, idProduct=2303
Mar 14 18:18:45 localhost kernel: usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=0
Mar 14 18:18:45 localhost kernel: usb 2-1: Product: USB-Serial Controller
Mar 14 18:18:45 localhost kernel: usb 2-1: Manufacturer: Prolific Technology Inc.

  so that looks good. and yet, no matter what i do, i can't get
minicom to connect to the console on /dev/ttyUSB0.

  i have all the right minicom settings, and i've connected before
thru my clunkier port replicator.

  simple question, then: is anyone using one of these converters to
talk to their BB? just so i know it can be done and i can look for
the problem elsewhere.

rday

I use a Airlink 101 usb->serial converter [1]. Supposedly it uses the
Prolific 2303 driver [2]. But it just uses the generic usb serial
driver that comes default with linux. I can connect successfully to my
ubuntu 8.10 laptop, but I use GTKterm instead of minicom.

Only thing I can suggest is to get out the multimeter and check if
you're wiring is correct (short out pins 2 and 3 on your usb->serial
adapter to see if things are echoing back in minicom, etc, and make
sure that lines up with your IDC10->DB9 adapter).

Good luck!

- Dan

[1] http://www.airlink101.com/products/ac-usbs.php
[2] http://fundisom.com/apple/search/airlink-101/

You need a null modem.

no luck with gtkterm, either, so i'm starting to assume it's just
the (home-made) serial cable, which used to work fine but maybe it
just flaked out lately. thanks.

rday

already have one, so i'm just getting more and more baffled. i'll
play some more to try to figure out what incredibly dopey thing i've
done.

rday

Hi this is a very common usb2serial adapter and I use it all the time(not only for the beagle),
A gender changer is not enough you need a null-modem cable if you use the “default” “AT/Everex workalike) cable.”

What I did was to replace the pins and connector so I can directly attach the serial adapter to the beagle.

If you want to be sure it’s not minicom try picocom -b 115200 /dev/ttyUSB0

A usb to serial adapter together with the tincantools rs232 board from
http://www.tincantools.com/product.php?productid=16144&cat=0&page=1&featured
works fine for me.

rather than mess around with a full-blown port replicator to connect
to the console on my BB, i picked up a simple USB-serial converter and
am trying to use that to go from USB on my laptop to the serial port
at the other end, then a gender changer, and finally to the serial
(AT/Everex workalike) cable.

here's the converter cable:

http://www.prolific.com.tw/eng/Products.asp?ID=59

and when i plug it into my fedora 9 system, i see this in
/var/log/messages;

Mar 14 18:18:44 localhost kernel: usb 2-1: new full speed USB device using
uhci_hcd and address 69
Mar 14 18:18:45 localhost kernel: usb 2-1: configuration #1 chosen from 1
choice
Mar 14 18:18:45 localhost kernel: pl2303 2-1:1.0: pl2303 converter
detected
Mar 14 18:18:45 localhost kernel: usb 2-1: pl2303 converter now attached
to ttyUSB0

[...]

so that looks good. and yet, no matter what i do, i can't get
minicom to connect to the console on /dev/ttyUSB0.

Hi this is a very common usb2serial adapter and I use it all the time(not
only for the beagle),
A gender changer is not enough you need a null-modem cable if you use the
"default" "AT/Everex workalike) cable."

What I did was to replace the pins and connector so I can directly attach
the serial adapter to the beagle.

If you want to be sure it's not minicom try picocom -b 115200 /dev/ttyUSB0

Sorry for digging an old message, but I can confirm pl2303 didn't
work for me either. I tried on a PC with a serial port and everything
went fine, so it's no NULL modem issue. But using the NULL modem
+ USB-serial didn't work.

Laurent

Bus 001 Device 005: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial
Port + a 30 foot NULL modem cable is working fine here.
Regards
Sid.

some of those USB-serial converters are simply crap. i originally
had a no-name converter that was prolific underneath, and i could
never get it to work. spent $20 on another one, /var/log/messages
still sees this one as prolific:

Oct 13 06:28:17 localhost kernel: usb 2-1: Product: USB-Serial Controller
Oct 13 06:28:17 localhost kernel: usb 2-1: Manufacturer: Prolific Technology Inc.
Oct 13 06:28:17 localhost kernel: usb 2-1: configuration #1 chosen from 1 choice
Oct 13 06:28:17 localhost kernel: usbcore: registered new interface driver usbserial
Oct 13 06:28:17 localhost kernel: USB Serial support registered for generic
Oct 13 06:28:17 localhost kernel: usbcore: registered new interface driver usbserial_generic
Oct 13 06:28:17 localhost kernel: usbserial: USB Serial Driver core
Oct 13 06:28:17 localhost kernel: USB Serial support registered for pl2303
Oct 13 06:28:17 localhost kernel: pl2303 2-1:1.0: pl2303 converter detected
Oct 13 06:28:17 localhost kernel: usb 2-1: pl2303 converter now attached to ttyUSB0
Oct 13 06:28:17 localhost kernel: usbcore: registered new interface driver pl2303
Oct 13 06:28:17 localhost kernel: pl2303: Prolific PL2303 USB to serial adaptor driver
Oct 13 06:28:18 localhost NetworkManager: <info> (ttyUSB0): ignoring
due to lack of mobile broadband capabilties

and it works fine via minicom. so be prepared to blame the converter,
and try another one just to play it safe.

rday

p.s. and, yes, don't forget that null modem cable.

p.p.s. the folks on the u-boot mailing list consider minicom to be a
piece of junk, although it seems to have worked well for me so far.

[...]

Sorry for digging an old message, but I can confirm pl2303 didn't
work for me either. I tried on a PC with a serial port and
everything went fine, so it's no NULL modem issue. But using the
NULL modem + USB-serial didn't work.

some of those USB-serial converters are simply crap. i originally
had a no-name converter that was prolific underneath, and i could
never get it to work. spent $20 on another one, /var/log/messages
still sees this one as prolific:

Oct 13 06:28:17 localhost kernel: usb 2-1: Product: USB-Serial Controller
Oct 13 06:28:17 localhost kernel: usb 2-1: Manufacturer: Prolific Technology Inc.
Oct 13 06:28:17 localhost kernel: usb 2-1: configuration #1 chosen from 1 choice
Oct 13 06:28:17 localhost kernel: usbcore: registered new interface driver usbserial
Oct 13 06:28:17 localhost kernel: USB Serial support registered for generic
Oct 13 06:28:17 localhost kernel: usbcore: registered new interface driver usbserial_generic
Oct 13 06:28:17 localhost kernel: usbserial: USB Serial Driver core
Oct 13 06:28:17 localhost kernel: USB Serial support registered for pl2303
Oct 13 06:28:17 localhost kernel: pl2303 2-1:1.0: pl2303 converter detected
Oct 13 06:28:17 localhost kernel: usb 2-1: pl2303 converter now attached to ttyUSB0
Oct 13 06:28:17 localhost kernel: usbcore: registered new interface driver pl2303
Oct 13 06:28:17 localhost kernel: pl2303: Prolific PL2303 USB to serial adaptor driver
Oct 13 06:28:18 localhost NetworkManager: <info> (ttyUSB0): ignoring
due to lack of mobile broadband capabilties

and it works fine via minicom. so be prepared to blame the converter,
and try another one just to play it safe.

I tested another pl2303-based USB serial cable a colleague
had, and it worked. This looks like a lottery :slight_smile:

Laurent