Hello Mark!

  MW> I've got an elderly T1910 laptop with a 640x480 LCD
    > display; it'd be nice to use it all at (say) 80x48
    > characters in an 8x10 font.  In normal text modes (at
    > 640x400 pixels) there's a 640x40 blank area at the top
    > and bottom of th screen.

Until recently I was displaying the output from a NetBSD box
onto a display with a visible diagonal of about 15.5".  80 x
25 text spread across that looked big, and kind of grainy. I
would have like the option of a 120 x 45 text mode console,
to take me back to 10cpi, 5lpi (I'd wind the borders in to a
15" picture).

I have no idea whether this mode is any kind of (VESA?)
standard, or how much work it would take to provide that
kind of console.  For me personally it wasn't important
enough to make time to investigate, but I understand that
people's situations differ.  I'd created the 'problem' by
running the box on the 15.5" monitor (I have to say that
X looked great on it though!  :-)

I'm running NetBSD on another machine now, and temporarily
have a smaller VGA monitor attached so that I can keep an
eye on console output.  I'm probably a few days away from
disconnecting that and running headless.  I may try a serial
console then.

  MW> Can anybody point me in the right direction for
    > getting the top memory offset right?  I've played a
    > bit, but so far haven't managed to get any text in
    > that bit of display.

Sorry, I don't know.  I think the original VGA did text with
a 9x16 font, at the equivilent of 720x400.  Your laptop may
use an 8x16 font, which at 400 lines would leave 40 line
borders top and bottom.  Be thankful it's not trying to
'stretch' the text as some laptops do - that looks awful.

It's probably not very practical on a PC, but I stumbled
across /usr/src/sys/arch/mac68k/dev/6x10.h the other day,
which could yield something like 106 columns x 48 rows on a
640x480 pixel screen.  I believe it's used on 512x384 Mac
displays for an optional 85 x 38 console.

Regards,
  - Andy Ball.