VGA(4) BSD Programmer's Manual VGA(4)NAMEvga - VGA graphics driver for wscons
SYNOPSIS
vga0 at isa?
vga* at pci?
wsdisplay* at vga? console ?
option PCIAGP
DESCRIPTION
This driver handles VGA graphics hardware within the wscons(4) console
framework. It doesn't provide direct device driver entry points but makes
its functions available via the internal wsdisplay(4) interface.
The vga driver supports multiple virtual screens on one physical display.
The screens allocated on one display can be of different "types", where a
type refers to various display properties. The type is determined at the
time the virtual screen is created and can't be changed later. Screens
are either created at kernel startup (then the default type is used) or
later with help of the wsconscfg(8) utility.
Currently, the following screen types are supported:
80x25 This is the standard VGA text mode with 80 columns and 25 rows.
16 different colors can be displayed at the same time. Characters
are 8 x 16 pixels large, and a font consists of 256 characters. A
built-in font of this size is always present on a VGA card. It's
also possible to use a downloaded font instead.
80x25bf A modified version of the previous. It only allows 8 colors to be
displayed. In exchange, it can access two fonts at the same time,
so that 512 different characters can be displayed.
80x40 A text mode with 80 columns and 40 rows. Similar to the standard
mode, 16 colors and 256 characters are available. Characters are
8 x 10 pixels large. For this mode to be useful, a font of that
character size must be downloaded.
80x40bf A modified version of the previous. It only allows 8 colors to be
displayed. In exchange, it can access two fonts at the same time,
so that 512 different characters can be displayed.
80x50 A text mode with 80 columns and 50 rows. Similar to the standard
mode, 16 colors and 256 characters are available. Characters are
8 x 8 pixels large. For this mode to be useful, a font of that
character size must be downloaded.
80x50bf A modified version of the previous. It only allows 8 colors to be
displayed. In exchange, it can access two fonts at the same time,
so that 512 different characters can be displayed.
80x24 A variant of the "80x25" screen type which displays 24 lines
only. It uses the standard 8x16 VGA font. This mode might be use-
ful for applications which depend on closer DEC VT100 compatibil-
ity.
80x24bf A modified version of the previous. It only allows 8 colors to be
displayed. In exchange, it can access two fonts at the same time,
so that 512 different characters can be displayed.
The vga driver can display fonts of the original IBM type and ISO-8859-1
encoded fonts. As an experimental feature, the "higher half" fonts of the
former OpenBSD/i386 pcvt driver distribution can be used too if option
WSCONS_SUPPORT_PCVTFONTS was set at kernel compile time. This is only
useful with the "*bf" screen types; a font containing the ASCII range of
characters must be available too on this screen.
option PCIAGP enables support for the AGP GART programming through the
ioctl(2), for use by the XFree86(1) on some architectures.
SEE ALSOintro(4), isa(4), pcdisplay(4), pci(4), wscons(4), wsdisplay(4),
wsconscfg(8), wsfontload(8)BUGS
Only a subset of the possible text modes is supported.
VGA cards are supposed to emulate an MDA if a monochrome display is con-
nected. In this case, the device will naturally not support colors at
all, but offer the capability to display underlined characters instead.
The "80x25bf", "80x40bf", "80x50bf", and "80x24bf" screen types will not
be available. This mode of operation is not tested.
MirOS BSD #10-current March 20, 1999 1
