From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 10 Jun 1999 16:57:32 -0400 From: Daniel Jacobowitz To: linuxppc-dev@lists.linuxppc.org Subject: Re: Q: control is a C&T 65550? Message-ID: <19990610165732.A3984@drow.res.cmu.edu> References: <19990608095844.A5496@drow.res.cmu.edu> <199906102051.WAA00299@piglet.cpu.lu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <199906102051.WAA00299@piglet.cpu.lu>; from Michel Lanners on Thu, Jun 10, 1999 at 10:51:08PM +0200 Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: On Thu, Jun 10, 1999 at 10:51:08PM +0200, Michel Lanners wrote: > - The RAMDAC is an Apple ASIC as well, named RaDaCal, integrating the > RAMDAC, CLUT and a hardware cursor device. Use and programming of the > hardware cursor are yet undocumented. The known details are that the > cursor needs to be drawn by the OS as some kind of sprite, in an > offscreen VRAM portion reserved at the end of each scanline. The > vertical position needs to be drawn at the right offset, whereas the > horizontal position of the cursor is taken care of by RaDaCal, probably > by setting the horizontal position info in a register. Vertical > movements therefore need a redraw by the OS. I intend to see what I can do about documenting the hardware cursor. With all the excellent advice I've gotten, I expect it won't be too difficult. > Obviously, all of the above information can be totally wrong ;-). If > there is any Apple engineer in the audience who knows better, please do > speak up! Unfortunately, the Apple engineers in the audience aren't allowed to :( Dan /--------------------------------\ /--------------------------------\ | Daniel Jacobowitz |__| SCS Class of 2002 | | Debian GNU/Linux Developer __ Carnegie Mellon University | | dan@debian.org | | dmj+@andrew.cmu.edu | \--------------------------------/ \--------------------------------/ [[ This message was sent via the linuxppc-dev mailing list. Replies are ]] [[ not forced back to the list, so be sure to Cc linuxppc-dev if your ]] [[ reply is of general interest. Please check http://lists.linuxppc.org/ ]] [[ and http://www.linuxppc.org/ for useful information before posting. ]]