NAME    [Toc]    [Back]

     wsdisplay - generic display device support in wscons

SYNOPSIS    [Toc]    [Back]

     wsdisplay* at vga? console ?
     (VGA textmode display on ISA or PCI)
     wsdisplay* at pcdisplay? console ?
     (generic PC (ISA) display)
     wsdisplay* at vgafb? console ?
     (VGA graphics display on PCI, as found on macppc and sparc64
platforms)
     wsdisplay* at tga? console ?
     (DEC TGA display, alpha only)
     wsdisplay* at sti? console ?
     (HP CRX and Visualize series framebuffers)
     wsdisplay* at agten? console ?
     wsdisplay* at bwtwo? console ?
     wsdisplay* at cgtwo? console ?
     wsdisplay* at cgthree? console ?
     wsdisplay* at cgfour? console ?
     wsdisplay* at cgsix? console ?
     wsdisplay* at cgeight? console ?
     wsdisplay* at cgtwelve? console ?
     wsdisplay* at cgfourteen? console ?
     wsdisplay* at mgx? console ?
     wsdisplay* at pninek? console ?
     wsdisplay* at pnozz? console ?
     wsdisplay* at rfx? console ?
     wsdisplay* at tcx? console ?
     wsdisplay* at tvtwo? console ?
     wsdisplay* at vigra? console ?
     wsdisplay* at zx? console ?
     (sparc and/or sparc64 framebuffers)
     wsdisplay* at creator? console ?
     (sparc64 framebuffers)
     wsdisplay0 at smg? console ?
     (VAXstation small monochrome display)
     option WSDISPLAY_DEFAULTSCREENS=N

DESCRIPTION    [Toc]    [Back]

     The wsdisplay driver is an abstraction layer for display devices within
     the wscons(4) framework.  It attaches to the  hardware  specific display
     device  driver  and  makes  it available as text terminal or
graphics interface.


     A display device can have the ability to display  characters
on it (without
  help  of  an  X server), either directly by hardware or
through software
     drawing pixel data into the display memory.   Such  displays
are called
     ``emulating'',  the wsdisplay driver will connect a terminal
emulation
     module and provide a tty-like software interface.   In  contrary, non-emulating
  displays can only be used by special programs like X
servers.

     The console locator in the configuration line refers to  the
device's use
     as  output  part  of the operating system console.  A device
specification
     containing a positive value here will only match if the  device is in use
     as  system  console.  (The console device selection in early
system startup
     is not influenced.)  This way, the  console  device  can  be
connected to a
     known wsdisplay device instance.  (Naturally, only ``emulating'' display
     devices are usable as console.)

     The logical unit of an independent contents displayed  on  a
display (sometimes
  referred  to  as  ``virtual  terminal'')  is called a
``screen'' here.
     If  the  underlying  device  driver  supports  it,  multiple
screens can be used
     on  one  display.   (As of this writing, only the vga(4) and
the VAX ``smg''
     display drivers provide this ability.)  Screens have different minor device
  numbers  and  separate tty instances.  One screen possesses the
     ``focus'', this means it is displayed on the display and its
tty device
     will  get  the keyboard input.  (In some cases, if no screen
is set up or
     if a screen was just deleted, it is possible that  no  focus
is present at
     all.)   The focus can be switched by either special keyboard
input (typically
 CTL-ALT-Fn) or an ioctl command issued by a user  program.  Screens
     are  set  up or deleted through the /dev/ttyCcfg control device (preferably
     using the wsconscfg(8) utility).   Alternatively,  the  compile-time option
     WSDISPLAY_DEFAULTSCREENS=N will set up N screens of the display driver's
     default type and using the system's default terminal  emulator at autoconfiguration
 time.

     In addition and with help from backend drivers the following
features are
     also provided:

     +o   Loading, deleting and listing the loaded fonts.

     +o   Browsing backwards in the screen output, the size of the
buffer for
         saved text is defined by the particular hardware driver.

     +o   Blanking the screen by timing out on inactivity  in  the
screen holding
         the input focus.  Awakening activities consist of:

         +o   pressing any keys on the keyboard;
         +o   moving or clicking the mouse;
         +o   any output to the screen.

         Blanking  the  screen  is  usually done by disabling the
horizontal sync
         signal on video output, but may  also  include  blanking
the vertical
         sync  in  which  case most monitors go into power saving
mode.  See
         wsconsctl(8) for controlling variables.

     Consult the back-end drivers' documentation for  which  features are supported
 for each particular hardware type.

FILES    [Toc]    [Back]

     /dev/tty[C-F]*                       terminal  devices  (per
screen)
     /dev/tty[C-F]cfg                     control   device   (per
screen)
     /usr/include/dev/wscons/wsconsio.h

SEE ALSO    [Toc]    [Back]

     agten(4),  bwtwo(4),  cgeight(4),  cgfour(4), cgfourteen(4),
cgsix(4),
     cgthree(4),  cgtwelve(4),  cgtwo(4),  creator(4),  intro(4),
mgx(4),
     pcdisplay(4),  pninek(4),  pnozz(4), rfx(4), sti(4), tcx(4),
tga(4),
     tty(4), tvtwo(4),  vga(4),  vgafb(4),  vigra(4),  wscons(4),
zx(4),
     wsconscfg(8), wsconsctl(8), wsfontload(8)

BUGS    [Toc]    [Back]

     The wsdisplay code currently limits the number of screens on
one display
     to 8.

     The terms ``wscons'' and ``wsdisplay'' are not cleanly  distinguished in
     the code and in manual pages.

     ``non-emulating'' display devices are not tested.

OpenBSD      3.6                        February     29,     2004