nanogui: Drawing modes
Subject:
Re: Drawing modes
From:
Ben Pfaff ####@####.####
Date:
19 May 1999 23:26:30 -0000
Message-Id: <871zgcskkm.fsf@pfaffben.user.msu.edu>
Greg Haerr ####@####.#### writes:
On Wednesday, May 19, 1999 5:21 PM, Ben Pfaff ####@####.#### wrote:
> Greg Haerr ####@####.#### writes:
>
> I'm talking about the planar modes, which are a pain in the ass.
> I thought you were working on the vga16 driver, which uses the planar modes.
> In the planar mode, the hardware is setup the way I've been describing.
>
> Yeah, but you still need two memory accesses, one to load the latches,
> one to store them. If you've got a fun magic way to avoid this, let
> us know!
No, thats why the |= operator works so well, it generates a read followed
by a write bus cycle...
Now I'm really confused. Isn't that still read-modify-write? It's a
read, followed by modifying the data, followed by a write. Maybe we
need some better definitions. How do you define rmw?
--
"...In the UNIX world, people tend to interpret `non-technical user'
as meaning someone who's only ever written one device driver."
--Daniel Pead
