1.\" $OpenBSD: udl.4,v 1.19 2011/03/16 23:36:38 schwarze Exp $ 2.\" 3.\" Copyright (c) 2009 Marcus Glocker <mglocker@openbsd.org> 4.\" 5.\" Permission to use, copy, modify, and distribute this software for any 6.\" purpose with or without fee is hereby granted, provided that the above 7.\" copyright notice and this permission notice appear in all copies. 8.\" 9.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16.\" 17.Dd $Mdocdate: March 16 2011 $ 18.Dt UDL 4 19.Os 20.Sh NAME 21.Nm udl 22.Nd DisplayLink DL-120 / DL-160 USB display devices 23.Sh SYNOPSIS 24.Cd "udl* at uhub?" 25.Cd "wsdisplay* at udl?" 26.Sh DESCRIPTION 27The 28.Nm 29driver supports USB display devices based on the DisplayLink DL-120 / DL-160 30graphic chip. 31.Sh HARDWARE 32The following devices should work: 33.Pp 34.Bl -tag -width Ds -offset indent -compact 35.It Century Corp. Japan Plus One LCD-8000U 36.It Century Corp. Japan Plus One LCD-4300U 37.It DisplayLink USB to DVI 38.It ForwardVideo EasyCAP008 USB to DVI 39.It HP USB 2.0 Docking Station (FQ834) 40.It HP USB Graphics Adapter (NL571) 41.It IOGEAR USB 2.0 External DVI (GUC2020) 42.It Koenig CMP-USBVGA10 and CMP-USBVGA11 43.It Lenovo 45K5296 USB to DVI 44.It Lilliput UM-70 45.It Nanovision MiMo UM-710 and UM-740 46.It Rextron VCUD60 USB to DVI 47.It Samsung LD220 48.It StarTech CONV-USB2DVI 49.It Sunweit USB to DVI 50.It Unitek Y-2240 USB to DVI 51.It VideoHome NBdock1920 52.El 53.Sh FILES 54The device can process compressed data (Huffman pixel difference method) 55to reduce the USB payload. 56To generate the compressed data, 57the driver needs to load a Huffman table, 58which is stored in the following binary file: 59.Pp 60.Bl -tag -width Ds -offset indent -compact 61.It Pa /etc/firmware/udl_huffman 62.El 63.Pp 64If the Huffman table can't be loaded, the driver will fall back to 65uncompressed mode. 66.Sh SEE ALSO 67.Xr intro 4 , 68.Xr usb 4 , 69.Xr wscons 4 , 70.Xr wsdisplay 4 71