UDL(4)

NAME
udl - DisplayLink DL-120 / DL-160 USB display devices

SYNOPSIS
udl* at uhub?
wsdisplay* at udl?

DESCRIPTION
The udl driver supports USB display devices based on the DisplayLink DL-120 / DL-160 graphic chip.

HARDWARE
The following devices should work:

Century Corp. Japan Plus One LCD-8000U
Century Corp. Japan Plus One LCD-4300U
DisplayLink USB to DVI
ForwardVideo EasyCAP008 USB to DVI
HP USB 2.0 Docking Station (FQ834)
HP USB Graphics Adapter (NL571)
IOGEAR USB 2.0 External DVI (GUC2020)
Koenig CMP-USBVGA10 and CMP-USBVGA11
Lenovo 45K5296 USB to DVI
Lenovo ThinkVision LT1421
Lilliput UM-70
Nanovision MiMo UM-710 and UM-740
Rextron VCUD60 USB to DVI
Samsung LD220
StarTech CONV-USB2DVI
Sunweit USB to DVI
Unitek Y-2240 USB to DVI
VideoHome NBdock1920

FILES
The device can process compressed data (Huffman pixel difference method) to reduce the USB payload. To generate the compressed data, the driver needs to load a Huffman table, which is stored in the following binary file:

/etc/firmware/udl_huffman

If the Huffman table can't be loaded, the driver will fall back to uncompressed mode.

SEE ALSO
intro(4), usb(4), wscons(4), wsdisplay(4)

HISTORY
The udl driver first appeared in OpenBSD 4.6.

AUTHORS
Marcus Glocker <mglocker@openbsd.org>