Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sdd.hp.com!wuarchive!uunet!zephyr.ens.tek.com!tekchips!tekgvs!toma
From: toma@tekgvs.LABS.TEK.COM (Tom Almy)
Newsgroups: comp.binaries.ibm.pc.d
Subject: Re: NNANSI.SYS
Keywords: problems with reversed video in mixed display
Message-ID: <8584@tekgvs.LABS.TEK.COM>
Date: 12 Dec 90 22:15:22 GMT
References: <266@dogear.UUCP>
Reply-To: toma@tekgvs.LABS.TEK.COM (Tom Almy)
Organization: Tektronix, Inc., Beaverton,  OR.
Lines: 57

In article <266@dogear.UUCP> root@dogear.UUCP (Bob Kirkpatrick) writes:
>The recently posted NNANSY.SYS set has a couple of problems that I noticed.
>I downloaded a previous version of nnansi, and tried it for a while. It had
>the speed advertised, but also a very annoying quirk.

>The best example is whn using pagers like 'MORE' (the pd version, not DOS) and
>foobar's fsuucp or even in a 'fancy prompt'. When a program uses a reversed or
>color background which doesn't use the entire screen, the reversed video bar,
>or the color background area appears at the top of the screen, while the text
>appears on the current screen line. It looks like this:
[example deleted]

The author replies:
	I would guess (judging by past experience) that the problem is
related to the NNANSI fast scrolling feature rather than reverse video.

	NNANSI obtains fast scrolling by altering the display start address.
It is compatible with programs that check the address (it is documented),
but has problems with programs which don't. NNANSI does contain code which
checks for problem programs, but it doesn't always work.

	The documentation suggests running NNANSI in "slow" mode for 
such programs. There is a supplied file, SLOW.BAT, that changes to slow
mode. Slow mode is also required for programs that want multiple display
pages. I suggest that Bob try slow mode before giving up. I also request
that he send me the PD more program if this doesn't fix the problem, so
that I can look at it (the PICNIX more that I have doesn't use reverse
video, and the commercial MKS more doesn't exhibit this problem).
	
>nnansi.sys is very fast, but, in my opinion, should only be used on mono-
>chrome systems which don't support color or reverse(!) video.

Actually, NNANSI provides better color support than the others. NNANSI
lets you turn reverse video off without reseting the colors. One "gotcha"
is that NNANSI correctly handles the foreground and background color
setting commands while in reverse video (i.e., if you change the foreground
color, the background color actually changes because it is reversed!).
Also NNANSI gives full color support in 16 color graphic modes -- you can set
the background color! 
I wrote the following fancy prompt to check operation:

prompt $e[7m$e[s$e[1;50H$t $d$e[K$e[u$p$g$e[27m

This prompt goes to reverse video, saves the cursor position, goes to the
top of the display, writes the time and date, erases to end of line, 
restores the cursor, prints the current drive/directory a right angle bracket,
and then leaves reverse video. It works just fine on my system.


>TO THE AUTHOR: *please* keep trying, nnansi is great except for this problem!

As I said, please slow mode. Then if that doesn't work send me a copy of
the more program. 90% of bug reports I get are solved by using slow mode.

Tom Almy
toma@tekgvs.labs.tek.com
Standard Disclaimers Apply