🚀 go-pugleaf

i want to reprogram the vga hardware registers (the crtc) to update the
vertical retrace more often.  instead of painting the entire screen, i
would like to start the vertical retrace at 1/2 screen (or 1/4, 1/8th...),
which would mean the portion of the screen i'm writing is updated faster
than the normal 60 or 70 hz.  since i'm not writing the entire screen, the
monitor should be able to handle the faster retrace, since the overall
bandwidth remains the same.

i have some books on the crtc controller registers, but they skip over
the exact details on how to do this with the words, "you don't need to
do this, and it's dangerous."  i understand trying to force the monitor
to handle more bandwidth than it's capable of is dangerous, but that is
not my goal.

does anyone have a pointer to a _complete_ book, or source code in any
language, or a _detailed_ description of the vga crtc registers, or a
pointer to a software package that already implements this?  thanks.


-- 
jack velte     velte@wam.umd.edu
cat psychology | computer_science > opinions