[comp.binaries.ibm.pc.d] EGA/VGA 35/40 line mode

roelofs@nas.nasa.gov (Cave Newt) (05/12/91)

ab2r@quads.uchicago.edu (Marshall Abrams) writes:

>I like VGAMoire a lot.  But what I would really like is a similar
>program that would restore my 40-line mode (VGA) screen properly.
>VGAMoire handles 50-line mode perfectly, but it restores 40-line mode
>with characters from another mode.  This means that the bottoms of all
>the characters are cut off.  Anyone know of a program that will
>restore 40-line characters properly?

The VGA 40-line mode (EGA 35) is generated from the same CGA 8x8 font that
is used in the 50- (43-) line mode, but it requires some extra fooling 
around to extend the characters to an 8x10 box.  In particular, the graphics 
characters must be "sign-extended" rather than "zero-extended," so to speak, 
else there will be gaps in your character-mode boxes/pictures/whatever.
Very few programs are aware of this mode, even some of those that use it 
themselves (e.g., Telemate).

Since you already have a way to get into this mode, I assume you're looking
for a *screen-blanker* program that restores the mode properly, and I can't
help you with that.  But I have my own little utility to switch to the mode
(assembler source included), and I'd be willing to send this to you or any-
one else that wants it.  Some of the available screen-blankers have source
included, too, so you could patch my code in one of them.

What, you say you wanted an EASY answer?  Ha ha, we charge extra for those...
:-)

Greg