Usb to serial problems

[Daryl Sayers]

I had an Aten USB to Serial device attached to an old laptop running
FreeBSD 4.7. I am now upgrading to much newer IBM thinkpad (A21m) :-)
I have installed FreeBSD 4.10 onto this machine and am now trying to
get the Aten to work. I have rebuilt the kernel with the extra devices:

device          ucom
device          uplcom

and I can see the device in dmesg:

usb0: <Intel 82371AB/EB (PIIX4) USB controller> on uhci0
usb0: USB revision 1.0
uhub0: Intel UHCI root hub, class 9/0, rev 1.00/1.00, addr 1
uhub0: 2 ports with 2 removable, self powered
ucom0: Prolific Technology Inc. USB-Serial Controller, rev 1.10/3.00, addr 2

Also the following command shows:
# usbdevs -vd
Controller /dev/usb0:
addr 1: full speed, self powered, config 1, UHCI root hub(0x0000), Intel(0x0000), rev 1.00
  uhub0
 port 1 addr 2: full speed, power 100 mA, config 1, USB-Serial Controller(0x2008), Prolific Technology Inc.(0x0557), rev 3.00
   ucom0

I am able to connect to /dev/ucom using minicom and I can send data via the
Aten to a remote computer. I am however unable to receive data at all. This
same laptop has Windoze installed on a second partition and using hyperterm
I am able to communicate in both directions. This means there is no problems
with the usb port,cabling or the Aten device. This brings it down to a
software issue. In the old days, this would have been an IRQ problem or
similar but with USB I am at a loss. 
  
I did also try running the usbd by adding the 'usbd_enable="YES"' in
/etc/rc.conf but this does not seem to have any effect on result.

Any ideas would be appreciated..

-- 
Daryl Sayers
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