KON(1) Kanji cONsole emulator


kon [ video ] [ -capability value ... ]


KON is a program to display Kanji characters on a virtual console of Linux and FreeBSD.

KON uses pty(4) to hook the I/O for console, and displays Kanji characters by drawing the image of them on VGA or DCGA.

KON can be invoked from another KON. In this situation, new KON runs on newly opened virtual console.


KON has ability to interpret some options to specify the video driver to be used, or some other environmental conditions. video is to specify one of video driver entries written in kon.cfg. If this option is omitted, then NORMAL video driver is used. Some settings as such as CursorInterval can be overridden by -capability options. For example,

   % kon -CursorInterval 10

invokes the kon with setting the value of CursorInterval to 10.


kon.cfg is the file to configure the behaviour of KON. Video drivers and Palettes used by KON is specified in this file. The format of an entry for this file is:



There are no distinction about case (upper/lower) in EntryName. Any line for "Value_for_Entry" must start with TAB. The part from # to the end of line, is treated as comment.

Types of "Value_for_Entry" are:

On / Off (no distinction about upper/lower case)
select one from options (no distinction about upper/lower case)
Decimal Number
Each entry has it's special format.

Following two entries are essential in this configuration file:

specify the video driver to be used. Available options are:

VGA      driver for VGA, SVGA, EGA
VGAFM    same above but with ability of font deformation
J3100SX  driver for TOSHIBA J3100SX (DCGA)

VGA and VGAFM require some parameters for
 VGA register value, screen size(Number of dots), Width(Number of characters), Hight(Number of lines).

Users can use this entry to change the total number of characters to be displayed, but except for VGA resolution(640x480), the number of characters that can be seen for the specified VGA register value, depends the video cards. Default kon.cfg set NORMAL as an alias for the standard VGA, and has some alternate entries for some video cards.

specify the command to be invoked at the start of KON. One line for each commands, but multiple lines can be specified. The command to load the fonts must be specified here. When the fonts for ASCII alphanumeric have not been loaded, then VGA font is used.

for the fonts file which is not compressed
  <fontloader> <Font file for ASCII alphanumeric>
  <fontloader> <Kanji/Kana font file>
for the fonts file which is compressed
  zcat <compressed font fine for ASCII alphanumeric> | <fontloader>
  zcat <compressed font file for Kanji/Kana> | <fontloader>

Next entry is required when VGA or VGAFM is specified as video driver:

specify the Pallete. The format is the pallette value(decimal) for R,G,B in each line, and 16 lines are there total. Default kon.cfg has STDPEL and REVPEL entries. STDPEL is the standard palette, and REVPEL is the reverse. PELS can be specified as an alias for used entry.

Other entries are:

specify the mouse driver. Select a type of mouse from Microsoft, MouseSystems, BusMouse, MMSeries, Logitech, None None is default.
specify the baud rate for serial mouse. Select one from 1200, 2400, 4800, 9600. Default is 1200. This is enabled when MOUSE is specified as others than NONE or BusMousees.
specify the device name of Mouse. Default is /dev/mouse. This is enabled when MOUSE has the entry other than None.
specify if the Mouse is 3-button type. Default is Off.
specify wheter hardware scroll is used or not. Default is On. This is effective for VGA, VGAFM, J3100SX.
specify the length of beep sound in the unit of 1/100 sec. Default is 5.
specify the interval of cursor blinking in the unit of 1/10 sec. Default is 4. To stop the blinking, specify 0.
specify the amount of time to start the screen saver in the unit of minutes. Default is 4.
specify if wide cursor is used on Kanji characters, or ot. Default is On.
specify the size of cursor box using these two entries.
      0 +--------+
        |        |
        |--------| <-- CursorTop
     15 +--------+ <-- CursorBottom
These are effective for VGA, VGAFM, and CGA drivers.
specify if the shape of cursor is box or under line. Default is Off. Effective for only J3100SX driver.
specify if the font data on 3rd page in VGA memory is saved. This is useful for Trident video cards. Default is Off. Effective for VGA, VGAFM drivers.
specify the offset value for VGA font. Default is 0. When the VGA fonts are used as ASCII alphanumeric font, there are some PCs the lower parts of characters are missing. In those circumstance, this entry can be used to adjust the position of displayed characters.
specify the default font and the coding in 1bit. The formats are:

       <SB font> <DB font> [EUC|SJIS]

SB font and DB font can be selected from:

    SB font: Single Byte font

    DB font: Double Byte font

specify if the greeting message is shown at startup. Default is On.

Configuratino for High resolution screen.

When VGA or VGAFM is used as video driver, KON can use the wider space for text area with the fine-tuing at kon.cfg.

       <VGA or VGAFM>

       [decimation factor for VGAFM]

       <HR> <HS> <HE> <HFL> <VR> <VS> <VE> <VFL>

       <Clock Number>

       <Line Width - 1> <Line Numbers - 1>

Control parameter in 3rd line for VGAFM (2nd line for VGA) consists of 8 decimal numbers. These numbers are similar as the video mode lines in XF86Config. KON can emulate text upto 800x600 resolution.

Screen control parameters:

HR total dot number in horizontal
HS the start point of horizontal sync
HE the end point of horizontal sync
HFL Total number of horizontal frames
VR number of vertical lines
VS the start point of vertical sync
VE the end point of vertical sync
VFL total number of vertical frames

Clock Number selects the clock frequency for the mode of that entry. Only lowest 2 bit is effective, i.e. a number from 0 to 3 can be specified here. The last line specifies the area for text screen to emulate.


/etc/kon.cfg          Configuratin file

/usr/share/fonts/kon/*  Font files

See Also


- When text screen is in high resolution mode at
  the start of LinuxKON can not work 
  successfully since the size of VGA font is 
  different from usual.
- When multiple entries with same name in kon.cfg,
 the first entry is used. The maximum length of one line 
 is 255 bytes.


MANABE Takashi           <[email protected]>
MAEDA Atusi              <[email protected]>
KOMEDA Shinji            <[email protected]>
YOSHIDA Kensyu           <[email protected]>
[email protected]