Subject: Re: PMAGB-B Scrolling/Clearing
To: NetBSD/pmax Discussion List <port-pmax@NetBSD.ORG>
From: Chris G. Demetriou <firstname.lastname@example.org>
Date: 07/21/2000 10:32:03
email@example.com (Greg A. Woods) writes:
> [ On , July 20, 2000 at 16:49:49 (-0700), Chris G. Demetriou wrote: ]
> > Subject: Re: PMAGB-B Scrolling/Clearing
> > There's no corresponding mechanism for the vtXXX console type, since
> > there isn't one on the real hw. 8-)
> Are we talking about scrolling one scan line at a time? I.e. "smooth
> If so then there sure as heck is! It's the first bit on the setup "B"
> screen of a real VT100 (0 = jump, 1 = smooth).
> Even if you're talking about "fast" scroll where two or more text lines
> will be scrolled at once if steady input is arriving then I'm reasonably
> sure that any DEC terminal newer than a vt220 (and maybe even including
> it too) does support such a feature.
Uh, that's not a 'corresponding mechanism' by a long shot; it's
entirely different. The sun console method does it via a an escape
code that can be issued to the terminal from software -- see the
source, or the manual pages from an old sun system (and maybe a
As far as I know, there's no way to do that on vtXXXs.
It _might_ be reasonable to implement it as a driver flag
(i.e. "... flags 0xsomething") or a kernel option. But really, the
better solution is to make accelerated moves work and then see if it's
(Also, if i recall, my experience was that 'smooth scroll' actually
had a different meaning than 'one line at a time', at least on my
vt220... but i'll admit that it's been a while.)