Text Mode Fonts

 BBS: Inland Empire Archive
Date: 09-16-82 (06:00)             Number: 298
From: RICH GELDREICH               Refer#: NONE
  To: ROB SMETANA @ 914/201         Recvd: NO  
Subj: Text Mode Fonts                Conf: (2) Quik_Bas
RS>   That's one type of approach we demonstrated in an article
RS>we just sent to Cleary for QBNews.  But a Clipper programmer
RS>mentioned a firm offering 4 fonts (full, I believe) at once.
RS>If true, like to know how they're doing it -- in TEXT mode.

        Simple,  with the VGA you can select between 256 characters
with blinking control,  or  512  characters without blinking control
for each  character  cell  on  the  screen.    (The  7th  bit of the
attribute byte in video memory controls blinking,  as  you  probably

        This is off the top of my  head,   but  once  this  mode  is
enabled  each  char/attribute in video memory works something like

        1st byte        2nd byte
        --------        --------
        First 8 bits    7  6  5  3  2  1  0
        of character    |  |  |  |  |  |  |
                        |  |  |  |  -------Foreground color, 3 bits
                        |  --------Background color, 3 bits
                        --This is the 9th bit of the character, 1 bit

        Do you see?   With 512 possible characters, you could have 4
fonts  of 128 characters,  or 8 fonts of 64.   I could give you some
more info if you want it...

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