The HyperNews Linux KHG Discussion Pages

Question: Vertical Retrace Interrupt - I need to use it

Forum: Device Drivers
Date: Wed, 04 Sep 1996 06:39:27 GMT
From: Brynn Rogers <>

I am writing an application that provides new images to the screen every vertical refresh. (Think of it as an animation)

As I understand it, I need to write a device driver to hook the vertical retrace interrupt (whatever interrupt your graphics card generates), and to install a new colormap so the next image is cleanly flipped in. (I don't need many colors, but I need lots of images).

I have been devouring all information (and donuts) I can get my hands on, and still am a little bit clueless as to how I should go about this. What I am really confused about is this: Should I have a device that my animation program opens and then uses ioctls to talk to, Just have the driver wake my process and signal it, or Something much better that somebody will clue me in on.

The driver only needs to know a few things, like which image planes are ready and the ID's? of the colormaps to use for which planes, and which screen or GC or whatever it needs.



1. None: Your choice... by Michael K. Johnson