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SCON(1)                 FreeBSD General Commands Manual                SCON(1)

     scon -- controls screen modes for pcvt video driver

     scon [-a] [-c screenno] [-d device] [-f on|off] [-h] [-H] [-l] [-m] [-v]
          [-V] [-s lines]
     scon [-v] [-d device] -p entry,red,green,blue
     scon [-v] [-d device] -p default
     scon [-v] [-d device] -p list
     scon [-v] -t timeout
     scon [-v] -1 | -8

     The scon utility controls several aspects of the runtime behaviour of the
     pcvt vt220 driver.

     The options are as follows:

     -a      Returns a string describing the video adaptor found by pcvt, the
             string returned could be MDA, HGC, CGA, EGA, VGA or UNKNOWN.

     -c      Specify the screen number the current (displayed) screen should
             be switched to.

     -d      Specify the device filename (i.e., /dev/ttyv2) further operations
             specified on the command line should be applied to.

     -f      Some programs which silently assume 24 lines when they run on a
             VT220 show incorrect behaviour when the terminal has really 25
             lines.  To support full VT220 behaviour, it is possible to force
             pcvt to select only 24 lines when it is running in 25-lines pure
             VT mode and/or in 28-lines HP-mode.  The -f option requires one
             additional parameter, the string 'on' or 'off' to switch this
             mode for a virtual screen on or off respectively.  This mode has
             no effect if any other vertical resolutions are selected than the
             two above mentioned.

     -h      Prints a usage/help text.

     -l      Lists the current configuration of runtime changeable options and
             fixed parameters (such as the type of the adaptor, and in case of
             a VGA adaptor, the Manufacturer, Chipset and 132 column support)
             of the output portion of the pcvt driver.

     -m      Returns a string describing the connected display monitor type
             found by pcvt, the string returned can be MONO, COLOR or UNKNOWN.

     -v      Specify verbose operation of the program.

     -V      Switch the specified/current screen into a pure VT220 mode with-
             out recognizing any HP escape sequences and without displaying
             function key labels.

     -H      Switch the specified/current screen into a mixed HP/VT220 mode.
             That is, that in addition to the full VT220 emulation, the HP
             function key labels and the escape sequences for handling the
             labels are available to the user.

     -s      Specify the number of character lines on the screen.  Possible
             parameters are 25, 28, 35, 40, 43 or 50.  To use all this screen
             sizes, the fonts required for proper operation of a desired size
             have to be downloaded to the EGA/VGA font ram.  This option is
             available only for EGA and VGA boards.

     -p      Modify VGA palette (DAC).  The -p is mutually exclusive with -s,
             -H, and -V.  Naturally, option -p is available only for VGA
             boards.  Three flavors are available.

             If used with argument ``default'', this flag will restore the
             default palette (as installed by VGA ROM BIOS after hardware

             If used with argument ``list'', the current VGA DAC palette
             entries are listed.  Each entry contains the table index, values
             for red, green, and blue, and if there is a known name for this
             entry, the color name.  Trailing empty table slots (RGB values
             all zero) are omitted.

             Otherwise, four comma-separated arguments are expected.  The
             first denotes the number of palette entry to be modified.  This
             may be either a number between 0 and 255, or the usual name of an
             associated color (case-insensitive).  The following values for
             red, green and blue are restricted to 0 through 63 due to VGA DAC
             conventions.  Note that the first delimiter within such an argu-
             ment may be a colon ``:'' instead of a comma ``,'' for better
             readability, but this violates common command argument conven-
             tions.  Multiple -p options may be specified if unambiguous.

     -t      Specifying -t will activate the screen saver.  The behaviour
             depends on timeout: if timeout is given as 0, the screen saver is
             turned off.  Otherwise, timeout is taken as a number of seconds
             to wait until activating the screen saver.  NOTE: the -t option
             is only available if screen saver support has been compiled into
             the driver!

     -1      Sets 132 columns mode (only available on VGA adaptors).

     -8      Sets 80 columns mode.

     When switching between HP and VT mode, when switching the force 24 lines
     mode on and off, or when switching between 80 and 132 columns operation,
     the screen is cleared, the scrolling region is reset and the cursor is
     placed in the home position.

     The command ``scon -H -s 28'' places the current screen into HP mode and
     sets the screen size to 28x80.

     Invoking ``scon -p lightgray,0,15,0 -p 0:45,45,45'' will result in green
     on gray output for normal text.  Note that normal text color is light
     gray, and not white as one might expect.

     cursor(1), loadfont(1), pcvt(4)

     the -c and -d options collide somehow, this will change in a future

FreeBSD 6.2                     March 27, 2000                     FreeBSD 6.2


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