Device Name for the tty on a USB to Serial Dongle

Russ · 10-14-2009, 09:23 PM

Because I work with Cisco gear, I absolutely, positively must have a serial port. I am running Ubuntu 8.10 on an old Compaq Armada E500 laptop. It does have a serial port at /dev/ttyS0 but one of the pins is physically failing on the male 9-pin and I'd like to get the USB to serial converter working. Can it be as simple as knowing the correct /dev/tty* device for the port in question? Any assistance would be great. TIA.

Russ

TB0ne · 10-14-2009, 09:40 PM

Quote:

Originally Posted by Russ

Because I work with Cisco gear, I absolutely, positively must have a serial port. I am running Ubuntu 8.10 on an old Compaq Armada E500 laptop. It does have a serial port at /dev/ttyS0 but one of the pins is physically failing on the male 9-pin and I'd like to get the USB to serial converter working. Can it be as simple as knowing the correct /dev/tty* device for the port in question? Any assistance would be great. TIA.

Russ

Should be something like /dev/ttyUSB0, etc. At least it usually is for me, on OpenSUSE.

smeezekitty · 10-14-2009, 09:58 PM

if the pin is still there and still works
i would plug an extension cord like plug into it
and never unplug it and hook the device to the other end
that way it does not physically strain the serial port any more

Russ · 10-15-2009, 12:11 AM

Quote:

Originally Posted by TB0ne

Should be something like /dev/ttyUSB0, etc. At least it usually is for me, on OpenSUSE.

Thanks TB0ne, there is one like that in /dev but it doesn't seem to work.

Russ

Russ · 10-15-2009, 12:16 AM

Quote:

Originally Posted by smeezekitty

if the pin is still there and still works
i would plug an extension cord like plug into it
and never unplug it and hook the device to the other end
that way it does not physically strain the serial port any more

Oddly enough, that is what I do now. I have my "sky-blue cable" plugged in and screwed down more or less permenantly. I am also looking ahead to when it does give up the ghost and to when I finally get a new laptop. None of the new crop (actually for a couple of generations now) comes with a serial port which is why I've stuck with "Old Faithful" for almost ten years.

Russ

TB0ne · 10-15-2009, 09:34 AM

Quote:

Originally Posted by Russ

Thanks TB0ne, there is one like that in /dev but it doesn't seem to work.

Russ

Huh...what does it do? Pardon the obvious question, but are you running minicom to talk to that port, and you've checked the baud rate, parity, etc? Also, do you have more than one /dev/ttyUSB device, and have you tried the others?

That device works fine for me, but I'm not talking to Cisco devices, though. Other serial devices work just fine, though, so this may be a settings issue (baud, etc.), or maybe you need a null-modem for your USB dongle. Just a thought...I've used these alot, and have always just used the /dev/ttyUSB* device.

Russ · 10-15-2009, 09:15 PM

Quote:

Originally Posted by TB0ne

Huh...what does it do? Pardon the obvious question, but are you running minicom to talk to that port, and you've checked the baud rate, parity, etc? Also, do you have more than one /dev/ttyUSB device, and have you tried the others?

That device works fine for me, but I'm not talking to Cisco devices, though. Other serial devices work just fine, though, so this may be a settings issue (baud, etc.), or maybe you need a null-modem for your USB dongle. Just a thought...I've used these alot, and have always just used the /dev/ttyUSB* device.

TB0ne,
It does work! I set the port in Minicom to /dev/ttyUSB0 and just on a hunch, I saved the setup, exited minicom and re-started it. It came up just fine and works great. When it didn't work, I was getting no blinking lights on my elderly Belkin dongle. Now the lights blink and it works great.

Thanks for your assistance, now I have another tool in my kit.

TB0ne · 10-16-2009, 12:40 PM

Quote:

Originally Posted by Russ

TB0ne,
It does work! I set the port in Minicom to /dev/ttyUSB0 and just on a hunch, I saved the setup, exited minicom and re-started it. It came up just fine and works great. When it didn't work, I was getting no blinking lights on my elderly Belkin dongle. Now the lights blink and it works great.

Thanks for your assistance, now I have another tool in my kit.

No problem, glad to be of help.