



                             Hercules Patch ver. 1.0
                                   WordStar 4

                                 By Matt Keveney
                                October 13, 1987

        The  accompanying  files  are for use with the  WordStar  4  Auto
        Patcher.   When  installed HERCVID.PAT provides a 43 line  by  90
        column   display   on  standard  Hercules   graphics   card   (or
        compatible).

        Use of this patch is NOT supported by MicroPro!

        License  to use this patch is granted to the public domain.   You
        may  distribute it freely, provided you include all three  files:
        HERCVID.PAT, INVERSE.PAT and this document, HERCVID.DOC.

        Features:

        *         Slower  performance than the standard  install.   It'll
                  probably  be acceptable only on machines that run at  a
                  fast clock rate.  (The screen is shifted into  graphics
                  mode.   Each  character is then painted on  the  screen
                  using the bit patterns located in the IBM ROM.)

        *         Extended  characters  on  screen if you  run  the   DOS
                  GRAFTABL program first.

        *         Almost  guaranteed NOT to work with TSR  programs  like
                  WordFinder.  If you accidentally invoke one,  sometimes
                  the screen can be recovered by "Running a DOS  command"
                  from within WordStar.  (Causes re-execution of INISUB.)

        *         Compatible with the Hercules Plus card, or the  InColor
                  card.  However  it  will not take  advantage  of  their
                  additional capabilities.

        *         Normal  text in reverse video available  by  installing
                  INVERSE.PAT  after installing HERCVID.PAT.  This  makes
                  the screen more readable with some monitors.


        Technical information:

        The  only  attribute supported is inverse video.  To  select  the
        items  that use it, patch the word at VIDATT+4 according  to  the
        bit  coding  described in PATCH.LST.  By default  it's  used  for
        everything  except extended characters, menu text, and the  ruler
        line.

        This  patch  resides in the VIDATT and EXTRA areas  described  in
        PATCH.LST.   Several  machine  language  routines  are  used   to
        initialize the screen, reset it when done, set video  attributes,
        and temporarily install video, and clock tick interrupt routines.



        The  video  routine  replaces  INT  10,  and  emulates  only  the
        functions WordStar 4 requires.  It is not a full BIOS emulation.

        Use of this patch is NOT supported by MicroPro!

        I may be reached by mail, however.  Send questions or comments to
        MicroPro,  attention  Matt  Keveney.  I'd like  to  hear  of  any
        compatibility  problems  in particular.  Unfortunately  I  cannot
        guarantee  a  timely response, as this is  not  official  company
        business.

        I hope you find this patch as useful as I have.


                                                  -Matt Keveney.




