VIDEOSETUP()
 Queries video mode at system start
------------------------------------------------------------------------------
 Syntax

     VIDEOSETUP() --> nVideoMode

 Returns

     The returned number designates which video mode is installed at system
     start.  The following codes apply:

     Table 6-5: Video Mode Coding
     ------------------------------------------------------------------------
     Code    Mode
     ------------------------------------------------------------------------
     0       Impossible to determine video mode
     1       Monochrome display w/color card & 40 columns
     2       Monochrome display w/color card & 80 columns
     3       Monochrome w/80 columns (HERCULES or IBM monochrome)
     ------------------------------------------------------------------------

 Description

     Depending on whether you have an XT or AT, this function returns the dip
     switch setting of the motherboard and/or the CMOS-RAM setting.

 Note

     .  VIDEOSETUP() always returns the video mode at the time of the
        booting.

 Example

     Display video mode of a monochrome system:

     ? VIDEOSETUP()            // returns:  3