usb ACM device doesn't work

Daniel O'Connor doconnor at
Sat Jun 22 04:37:38 UTC 2013

On 22/06/2013, at 4:10, Ian FREISLICH <ianf at> wrote:
> I bought a relay control board that has a USB interface.  It presents
> a serial port to Linux on /dev/ttyACMx.  However when I plug it
> into my FreeBSD host, it detects as follows:
> ugen0.2: <KMT> at usbus0
> umodem0: <KMT USB CDC COM, class 2/0, rev 1.10/1.00, addr 1> on usbus0
> umodem0: data interface 1, has no CM over data, has no break
> and I cannot communicate with it.  Any ideas how to communicate with it?

Have you tried anything?
It should create /dev/cuaUx and /dev/ttyUx (where x is 0 in your case)

Daniel O'Connor software and network engineer
for Genesis Software -
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