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Summary: Observations and Questions about Video Boards [message #112706] Mon, 16 September 2013 13:50
bob is currently offline  bob
Messages: 108
Registered: February 2013
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Message-ID: <591@tty3b.UUCP>
Date: Tue, 29-Jan-85 14:27:17 EST
Article-I.D.: tty3b.591
Posted: Tue Jan 29 14:27:17 1985
Date-Received: Wed, 30-Jan-85 07:24:02 EST
Organization: Teletype Corp., Skokie, Ill
Lines: 316

 >  I am shopping for an IBM PC and after much investigation I am still
 >  very confused about what to do for a video display card. The
 >  difficulty in obtaining information is frustrating.

** I would like to thank all who responded to my article from which the
** above is a quote. The variety of responses I received reflects the
** vast number of possibilities (vast amount of confusion) in this
** area. A summary follows:

+++++++++++++

** First, what may turn out to be the most useful response. This addition
** of PC magazine has not hit the news stands around here yet - I am
** waiting with anticipation.

Well, then you should be pleased to know that "PC Magazine" (February
19, 1985) has devoted its entire issue to "Focus on Video - 25 Eye-
Catching Boards for your IBM."  

Surely you will appreciate the mega-charts of physical characteristics,
performances and other features for both color and monochrome screens;
"some are good, some bad, and some are just pain ugly."

Check it out!

-- 
           .:.
           /.\                          michael regoli
          '|-|`         ...ihnp4!inuxc!iuvax!isrnix!mr
                                    indiana university

+++++++++++++

I originally got my IBM PC with a monochrome monitor, then later added the
color monitor so that I now have both boards in the system.  Even though I
have a printer port on my multifunction board, I don't want to give up the
monchrome monitor for text.  

Switching between them it is a bit of a pain, but it works.  It can be done
with either a command (MODE) or within a program (the Basic manual shows
the technique in one of the appendices).  I have even written programs
which dynamically switch between the two without losing the current screen
(i.e. using the monochrome for messages and input while displaying graphics
on the color monitor).  This requires deleting the SCREEN command from the
recommended sequence after the first time.

Both monitors and controllers are IBM.

Good luck.

Jim Moseman @ Perkin-Elmer, Tinton Falls, N.J.
.../vax135/petsd/jjm

+++++++++++++

I recommend the following:

	IBM Color/Graphics Board
	Inexpensive composite video (non-IBM) B/W monitor

This is the configuration that I have.  Advantages are:

1.  Compatible with everything.
2.  Text quality is excellent, even in 80 column mode.
3.  B/W graphics work fine.  Colors are displayed as various stipple
    patterns, hence are distinguishable, but just barely.  Text is
    beautiful in hi-res graphics mode.
4.  You can't do much better on price.  I'm using a 9" Hitachi monitor
    that I originally got for my Apple II + for about $250.
5.  Expandable if you want real colors.  Just plug in a color monitor
    (IBM or other) in addition to the B/W one.

Disadvantages are:

1.  Text in low-res graphics mode is pretty fuzzy.
2.  The stipple pattern colors are not as good as grey-scale would be.

I have yet to run software that depends on text in lo-res graphics.
But then, I don't play many games.

So, I think you can't do better price/performance wise than this.
If you want to add an inexpensive color monitor, you overcome the
disadvantages for about $300, and get real color.  I wouldn't get
stuck with the IBM monochrome card which doesn't feed anything but
an IBM monitor.  The NTSC Composite Video output on the color card
can connect to virtually anything.
					Doug Campbell
					doug@cornell.{UUCP|ARPA}

** I sent mail asking what Doug meant about high resolution on the
** color board, and received the following response.

The color/graphics board operates in 2 graphics modes and two text modes.
There are high and low resolutions versions of each.  The high-res text
mode gives 80-column text, the low-res text mode gives 40-column text.
The high-res graphics mode gives 600 X 200 pixels in black & white, the
low-res graphics mode gives 300 X 200 in 4 colors.  The text in hi-res
text mode looks just like the text in hi-res graphics mode.  The text in
lo-res text mode looks just like the text in lo-res graphics mode.
Though I don't know for certain, I have very good reason to suspect that
the monochrome board has identical resolution to the color board in
either hi-res mode.  The reason that the color board's text looks less
sharp on a color monitor than the monochrome's text on a monochrome
monitor is not due to the board - it's due to the monitor!  Color monitors
are necessarily less sharply focused than monochrome.  If you could
plug the monochrome board into a color monitor, you would see the same
lack of focus as with the color board on a color monitor.  Similarly,
plugging a monochrome monitor into a color board gives the same sharpness
as a monochrome board on a monochrome monitor.

						Doug Campbell
						doug@cornell.{UUCP|ARPA}

** I believe that the monocrome board and color board do not have
** identical resolution. The character matrix for the color board
** is 8x8 and the matrix for the monocrome board is 9x14. I don't
** question, however, what you are saying about text looking better
** on a monocrome monitor attached to a color board than on a color
** monitor attached to the color board. The real question is whether
** quality is acceptable with the color board and a monocrome monitor,
** not whether it is exactly the same as with a monocrome board.
** I find this solution very interesting.

+++++++++++++

I think you've summed up the dilemma rather nicely.  A couple of facts
that might help (if you don't already know them):

-	The salesman was giving you the straight story on the signal
	incompatiblity between IBM mono and IBM color; the sweep rate
	and raster pattern are different.  I believe someone has built
	a monitor that runs on both, but it is (1) expensive and (2)
	requires manual switching between modes.

-	The IBM graphics board uses a 640x200 raster pattern, giving
	only an 8x8 square for a character.  The way AT&T solves the
	problem is to use a 640x400 raster. This gives a 8x16 character
	in alpha mode (good quality) and true IBM compatibility in
	graphics mode (just use two dots of your raster for each
	dot of the IBM bitmap).  Two limitations: (1) you need a special
	monitor (400 lines) and a special (unavailable) display board,
	and (2) the characters in graphics mode aren't any better
	than IBM's.

				Dave Tutelman

+++++++++++++

	Basically, there are some other video board options.
STB makes a board that's essentially the IBM monochrome/printer
board and color graphics board put together (2 for the price
of one slot).  I think it's in the $300-$400 range.  A friend
of mine (who is a dealer) has used one of these with his
monochrome monitor for quite a while now.  As far as I know,
there are no compatibility problems.  There are switch settings
governing the choice of where it sends various outputs, including
sending graphics stuff to the monochrome monitor if that's the
only one connected, but I don't think that it actually gives you
monochrome graphics due to the signalling differences (at least,
my friend doesn't use it that way).  There is also a composite
video output from this board.
	When we bought our IBM, we bought the STB version of the
monochrome/printer card.  As far as we know (and we got it
recently, so we haven't tried anything wierd), there aren't
any compatibility problems, and it's cheaper.
	Other companies also make combination boards - I believe
the Tecmar Graphics Master (at ~$700, probably not one of your
first choices) provides monochrome as well as color output.
	Hope this is of some help...
		Vickie Klick ihu1h!klick x3451 IH4A-325
		AT&T Bell Laboratories, Naperville, IL

+++++++++++++

You might consider the Zenith Z150.  It comes with an IBM-compatible
color/graphics board that gives gray scale for colors when you use
the Zenith monitor.  You still git the 8x8 character which isn't as
pretty as the monochrome character set, and you don't get BASIC in ROM.
Still, it is a nice machine.
Tom Putnam
{decvax|harpo|ihnp4|inuxc|seismo|ucbvax}!pur-ee!pucc-h:ac4

+++++++++++++

On the IBM XT at work we have a mono board AND a color board, both plugged
into their respective mono and color IBM monitors.  It does seem to be an
expensive way around the problem, but it does indeed work.

It is very easy to transfer output from one screen to another, using the
"mode" command in 2.1 DOS.  Once a particular screen is invoked, all 
following video output will be on that screen unless you go back to DOS
and use "mode" again (or the program you are running is able to make
this change itself.  Some do, most don't.)

The problems, as I see them, are:

1) $money$.  This is expensive.

2)  Desk space.  Where are you going to fit TWO monitors?  This is a
    real pain at work.  The entire system (XT, keyboard, big printer,
    mouse space, work space, and two montiors) will not fit on a standard
    desktop.

3)  Computer space.  Two boards take up two slots.  What with all the
    stuff installed in our XT, we have no more room for the extra
    memory we really need.


I hope this helps.  (By the way, doesn't the Compaq machine have a place
where you can plug a COLOR monitor?)

-Rafe Needleman
 ...!tektronix!reed!rafe

+++++++++++++

Before you buy anything, check out the Enhanced Color Adapter from
IBM.  It is supposed to be as good as the monochrome adapter for
text and has all color adapter modes plus a high resolution mode.
And since it is from IBM, you can expect perfect compatibiity :-).
It was reviewed in PC magazine a few issues ago.

George B. Smith
National Semiconductor
...!{ihnp4!nsc | decvax!decwrl!nsc | ucbvax}!voder!gbs

+++++++++++++

Get the new "Enhanced Graphics" board.  It will drive the monochrome display
with good characters and graphics, and will drive a soon to be released
color display which will have nice characters and reasonable resolution 
color graphics.  It's an IBM product that runs about $500.  Local dealers
around here have had it available off and on for several months.

+++++++++++++

COMPAQ, not COMPACT.
----
Gene E. Bloch (...!nsc!voder!gino)
Support Bulgarian gajda players.

** sorry Gene

+++++++++++++

We have several IBM PC's in our group equipped with Everex Graphics Edge 
Color/Monochrome boards.  We bought them because they claim to be compatible 
with IBM mono, IBM color, and Hercules software.  I have run Framework 
in Hercules mode on an IBM direct drive monochrome monitor with 
excellent results.  The board operates with "IBM" color software 
driving a Taxan RGB monitor.  Everex supplies a BASIC program that 
demonstrates 640 X 200 resolution in 16 colors.  We have also used it to 
drive an Amdek 300 composite monochrome monitor in either color or 
monochrome mode.  The Amdek horizontal hold and vertical height controls 
must be readjusted when switching between modes.  The Amdek monitor 
did not work properly in Hercules mode for unknown reasons.  The manual 
indicates 16 level grey scale display is possible on a composite 
monochrome monitor driven in color mode, but we have not verified this.  

Jim Larsen

+++++++++++++

While it is probably safest to say that B&W monitors cannot  handle
both the B&W card and the color card, generally they can.  The
difference is between 15,750Hz and ~18KHz for the B&W.  That is likely
to take some cranking on the horizontal hold control.  Some monitors
can adjust that far, others can't.  Some have switches to make it
easy.

One hazard to be aware of:  using the composite output of the color
card, and many color cards not from IBM gives useless output for some
color images.  I don't think that was necessary, but they seem to
be that way.

+++++++++++++

** So, what am I going to do? I am almost afraid to say for fear of being
** flamed by those who recommended other solutions.
** 
** First, I am not going to do anything until I see that article in PC
** magazine. If that doesn't change my mind, I will do the following.
** 
** The cost of both the monocrome board and the color/graphics board combined
** is around the same as the cost of the fancier combination boards. The
** difference is the cost of the monitor. I have seen composite monocrome
** monitors that will plug into the color board for as little as $140.
** Another disadvantage of having both boards is that it uses up an
** extra slot - IF you need the slot.
** 
** There are other advantages to the combination of the two boards. Some
** programs (I am told lotus 123 is one) know how to display text on
** one monitor and graphics on the other. 123 doesn't interest me, but
** some other things do. The Feb 9 (?) issue of PC magazine has an article
** with a program that patches the keyboard interrupt to allow you to
** dynamically changes screens. This could be used to, say, display a
** help message on one screen, switch to a different screen and keep on
** working while the help message stays on the first screen. This is slightly
** crude, but according to the Whole Earth Software Catalog (a GREAT book),
** the program MEMORY/SHIFT expands this. With one monitor this program
** allows you to have multiple programs in memory at once, and switch back
** and forth (sounds like windows, not multiprocessing). If you have two
** monitors, you can run two different programs on the two monitors. This
** could be a real nice feature. You could compile a program on one screen
** without exiting the editor on the other screen. Anyone ever try
** MEMORY/SHIFT like this?
** 
** I have a friend that has a composite monocrome monitor that was once
** hooked up to his TRS 80 as an aux monitor. It is currently gathering
** dust in his closet, and he says I can use it. So, I plan to take that
** monitor into a computer store and see how it looks with the color board.
** If it looks ok, I will get only the color board. If it doesn't look
** good, I will get both the monocrome and color boards (and a monocrome
** monitor for the monocrome board).
** 
** ihnp4!tty3b!bob
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