USB->Serial adapter, how to make /dev/cuad* appear?

Benjamin Lutz mail at
Wed Oct 24 00:53:18 PDT 2007

Roland Smith wrote:
> On Tue, Oct 23, 2007 at 08:17:01PM +0200, Benjamin Lutz wrote:
>> On Tuesday 23 October 2007 19:54:44 Roland Smith wrote:
>>> On Tue, Oct 23, 2007 at 06:06:08PM +0200, Benjamin Lutz wrote:
>>>> I'd expect some device to show up in /dev, cuad1, ucom0, something
>>>> like that, but I get nothing. (cuad0 is taken by the onboard serial
>>>> port, which, alas, isn't wired to the outside of the case).
>>> Looking at ucom(4):
>>>      /dev/cuaU?
>>> See if that exists.
>> No such luck I'm afraid. There's only cuaU0, which belongs to the 
>> onboard serial port too.
> Does the onboard serial port work via USB? How odd! On my standard PC,
> the serial ports are driven by the sio driver, and have /dev/cuad* and
> /dev/ttyd* devices, noc cuaU. 

No, that one's a standard serial port, driven by sio as well, and
creates /dev/cuad0, /dev/cuaU0, maybe some /dev/tty* as well, I don't know.

> Do you have the correct driver for the converter loaded next to ucom?
> The ucom manual page gives a list of them.

Yes, uplcom is the right driver. (Or at least I think so, because the
device and manufacturer ids that usbdevs -v gives me match those in
/usr/src/sys/dev/usb/uplcom.c .) Besides, without the uplcom module
loaded, I only get an ugen device, so it seems to attach to the device ok.


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