Re: How to use an USB<->serial adapter?

[Greg KH <greg@kroah.com>]

On Thu, Aug 21, 2003 at 02:44:18PM +0200, Boszormenyi Zoltan wrote:
> Hi,
> 
> I am experimenting with a Prolific USB<->RS232 adaptor. We have
> in-house developments that need serial communication and there
> are more and more mainboards that provide only one RS232 connector.
> (We would need more in one machine...)
> So we decided to try an usb-serial converter. The one we bought
> was happily recognized by a RedHat 9 system but I couldn't get
> two-way communication over this converter.

Which kernel version are you using?

I didn't run your test programs, but are you sure you got the hardware
flow control settings correct?  How about testing the device with
minicom, as that is a program that is known to work properly with these
devices (along with lots of other ones, but that's a good place to
start.)

> setserial produces an error:
> 
> # setserial /dev/ttyUSB0
> Cannot get serial info: Invalid argument

Yes, setserial does not work with the majority of the usb-serial
drivers, patches gladly accepted to fix this :)

thanks,

greg k-h