From: becka@rz.uni-duesseldorf.de
  To  : ggi-develop@eskimo.com
  Date: Thu, 30 Jul 1998 15:38:10 +0200 (MET DST)

Re: I've seen the stars too... [Re: kgicon, etc]

Hi !

> Yes, assuming that today's PC video cards have a vblank interrupt.
> (I doubt busy waiting on the vblank register would be a good idea).

We shouldn't rely on it. Two reasons:

1. There are cards that can't. The SPEA Mercury is such a board. There is
a jumper on it which interrupts the INT line. Per defaults ints are off.
Moreover it is a hell of a "unlock this reg, I really want an INT" orgy to
get at it, if you set the jumper.

2. Many newer boards allow to disable giving an interrupt to the VGA and
sometimes this is even the default. This is done, because IRQs are running
low, when you have all and everything on board ...

However we could use some kind of timer which should be accurate enough ...

CU,ANdy

-- 
Andreas Beck              |  Email :  <Andreas.Beck@ggi-project.org>