Re: pl2303 Serial/USB problem - /dev/ttyUSB0 not created
On 09/08/10 17:41:28, Celejar wrote:
> On Fri, 06 Aug 2010 14:02:11 +0100
> Barry Samuels <barry@beenthere.mail1.co.uk> wrote:
>
> > Desktop and Laptop both have Debian Testing installed and up to date;
> > both with self-compiled kernel 2.6.32.
> >
> > I have a CurrentCost electricity usage monitor which is normally
> > connected to my desktop via USB and is working properly. When the unit
> > is plugged in I get a number of lines in syslog like so:
> >
> > kernel: usb 4-1: new full speed USB device using uhci_hcd and address
> > 12
> > kernel: pl2303 4-1:1.0: pl2303 converter detected
> > kernel: usb 4-1: pl2303 converter now attached to ttyUSB0
> >
> > I am trying to get this same device working on my laptop but this time
> > I see the following in syslog:
> >
> > kernel: pl2303: Prolific PL2303 USB to serial adaptor driver
> >
> > but nothing else i.e no 'attached to ttyUSB0'. Looking in /dev there
> > is no ttyUSBn
> >
> > Whereas the desktop also loads the pl2303 and usbserial kernel modules
> > automatically when the device is connected the laptop does not and
> > when I load them manually I get only the above mentioned line in
> > syslog.
> >
> > When the USB device is plugged in there is apparently no reaction from
> > the operating system on the laptop when watching /var/syslog using
> > 'tail'. That, I think, is the main problem. Other USB devices on the
> > laptop do work.
> >
> > Needless to say the software which monitors the device won't connect.
> >
> > Any suggestions please?
>
> Are you using the *exact* same kernel on both systems?
No of course not. One's a desktop the other's a laptop and they both have
different requirements e.g. different graphics drivers.
> Do you have the same problem with a Debian stock kernel? The first
> step when debugging problems with self-compiled kernels is always to
> check if the problem exists with stock kernels, or only with one's own.
I haven't tried a stock kernel but I have, since, tried a Knoppix Live DVD
in the laptop and it doesn't work with that either. No reaction from the
OS when the device is plugged in. I don't know if Knoppix uses a stock
kernel.
--
Barry Samuels
http://www.beenthere-donethat.org.uk
The Unofficial Guide to Great Britain
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