Subject: Re: wscons 50 rows
To: Todd Whitesel <toddpw@best.com>
From: Miles Nordin <carton@Ivy.NET>
List: current-users
Date: 01/24/2000 16:49:36
On Sun, 23 Jan 2000, Todd Whitesel wrote:
> the first console is currently hardwired to 80x24. [...] Thus the
> correct fix is: look at the port-atari stuff which has kernel options
> to load either the 80x24 or the 80x50 font into the console VGA
Does wscons on VGA use the text-mode of the VGA card?
If so, w.r.t. unicode and old fixed-frequency monitors, do you think it
would be of more-than-neglidgible benefit and improved simplicity to move
VGA-based ports to a bitmapped framebuffer by default? Would it help the
issue under discussion any?
I remember, for example, that Linux tried to do some svgatextmode stuff so
you could ask for an arbitrary text screen geomoetry w ith something like
an XFree86 modeline. It broke down to uselessness fairly quickly because
text modes do not access the memory in a sequential way--they randomly
read short segments out of the ``font'' area and jump around between each
character in a row. Modern video cards use special synchronous memory
that can keep up with high dotclocks only if it's scanned in-order, as it
is for a bitmapped console. The text dotclock limit was fairly low, 40 to
80Mhz. And this dotclock is for 1-bit, not-anti-aliased fonts.
I've been wondering about this for a long time but i'm pretty ignorant as
to the low-level issues involved w.r.t. NetBSD and compatibility with odd
cards. I've never actually seen anything but a serial console on
NetBSD/i386 because I have only fixed-frequency monitors. So this is
almost guaranteed to be a dumb question, but it would be considerable
effort for me to self-educate--appologies in advance.
--
Miles Nordin / v:+1 720 841-8308 fax:+1 530 579-8680
555 Bryant Street PMB 182 / Palo Alto, CA 94301-1700 / US