🚀 go-pugleaf

amead@s.psych.uiuc.edu (Alan Mead) writes:

>I thought I knew a thing or two about how VGA fonts work on the IBM
>PC...

>Then I happened to invoke a little programmer's tsr while in WordPerfect
>5.1 .  All the letters that the tsr used were strange greek, foreign,
>etc, symbols.  (This is while the prefectly normal charscters show on
>the screen.)

>I know how to change a font, but how do you make more than 256
>different chars appear on the screen?  And why would WordPerfect remap
>the normal a..zA..Z to something else?

>Thanks.  I'll be able to sleep again when I know.

>-alan

Hi All,

One way is to tell the EGA/VGA card that when the intensified attribute
is set it should display the character from the second character set.

  AX = 1103      ; intensified == 2nd character set
  BL = 04
  INT 10

  AX = 1000      ; Enable all planes
  BX = 0712
  INT 10

To disable (ie intensified is really intensified)

  AX = 1000
  BX = 0F12
  INT 10

If you can find a copy "PC Magazine September 16, 1986" had an articule
by Charles Petzold explaining the above techniques.

Hope this helps,

Jeremy

--
Jeremy Brown                      EMAIL: jb@materna.de
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