[comp.sys.amiga] How do you turn on flicker?

clp@altos86.UUCP (Chuck L. Peterson) (04/27/89)

I recently received an Amiga 2000 with a NEC Multisync II monitor
with the intention that I would put up with this flicker thing
until the "?new chips?" come out.

In the process of making a monitor cable, one of the loose
wires accidently touched something it shouldn't have; generating
a spark which seems to have broken the analog red in my monitor.
My monitor is in the shop now getting fixed.  

For the last week, I have been using my monitor in this hybrid
blue-green-only mode which is surprisingly acceptable.
However, I have not noticed any flicker.  Is this only because
my red doesn't work?

Chuck L. Peterson
 ...!sun.com!altos86!clp

LARSEN-D@osu-20.ircc.ohio-state.edu (Poindexter) (04/27/89)

Multisync's don't flicker, that's what you get for your extra 2-300 bucks.

dwi@manta.NOSC.MIL (Steve Stamper) (04/27/89)

Without a FlickerFixer Multisyncs DO flicker in the 400+ scanline
modes.
-Roger 

witting@topaz.rutgers.edu (Paul K Willing) (04/28/89)

In article <12489472380034@osu-20.ircc.ohio-state.edu> LARSEN-D@osu-20.ircc.ohio-state.edu (Poindexter) writes:

> Multisync's don't flicker, that's what you get for your extra 2-300 bucks.

Hey yo what?

You mean all I gotta do is get a multisync and no flicker?
Then whats the flicker fixer for?  the FF costs $500 from what Ive
seen, about what I could pick up a multisync for.

Now, if thats all there is to it, I ll go ahead and buy the Amiga
instead of the Mac IIcx, but my understanding says its much more
complicated than that.

Perhaps he has failed to activate the interlaced mode?

paul
-- 
----------------------------------------------------------------
Graphiti on the wall of civil rights organization in the sixties
 
	"There is a town in Mississippi named Liberty
         There is a Department in Washington called Justice"

A more socially aware sort of .sig     witting@topaz.rutgers.edu

mp1u+@andrew.cmu.edu (Michael Portuesi) (04/28/89)

> *Excerpts from ext.nn.comp.sys.amiga: 27-Apr-89 Re: How do you turn on flic..*
> *Poindexter@osu-20.ircc.o (76)*

> Multisync's don't flicker, that's what you get for your extra 2-300 bucks.

not true, unless you have an A2000 + flickerfixer.  they might flicker less than
the 1080/1084/2002, but they still flicker.  what you get for your extra
$200-$300 is the ability to use one monitor with a very wide range of video
outputs.

--
Michael Portuesi * Information Technology Center * Carnegie Mellon University
INET: mp1u+@andrew.cmu.edu * BITNET: mp1u+@andrew
UUCP: ...harvard!andrew.cmu.edu!mp1u+
MAIL: Carnegie Mellon University, P.O. Box 259, Pittsburgh, PA  15213

Sullivan@cup.portal.com (sullivan - segall) (04/28/89)

>I recently received an Amiga 2000 with a NEC Multisync II monitor
>with the intention that I would put up with this flicker thing
>until the "?new chips?" come out.
>
>Chuck L. Peterson
> ...!sun.com!altos86!clp

Flicker is caused by the 30 frame per second update rate.  The phosphor
in most CRTs is optimized for 1/60th of a second per page.  In interlace
mode the first screen is updated in 1/60th, and the second is updated 
during the next 1/60th.  The first is composed of all of the even scan
lines, and the second is composed of the odd ones.  Since the phosphor
has already died from the first screen by the time the second is being
shown, any bright points which neigbour dark ones vertically on the screen
will seem to disappear and reappear twice every 1/30th.  
 
The reason for this effect is complex.  Although 1/30th of a second should
be above the flicker rate for human visual perception, (movies typically)
run at 24 frames per second.) it is noticeable when compared to other
lines which are not flickering.  These other lines are the interlaced 
lines.  One effect that interlacing has on human visual perception is that
the slight upward/downward motion of the alternating lines is resolved 
automatically into a single line.  Thus the perceived resolution is half
of the actual resolution for an interlaced screen.  And as a net result,
successive lines which are light and dark seem to flicker.  

To experience this on your multisynch monitor, select the preferences
icon, choose some contrasty colors, and turn on the interlace.  After
saving your configuration reboot and you'll see your screen come to 
life.

 
                           -Sullivan Segall
_____________________________________________________________
 
/V\  Sully set the example: to fly without moving.  We shall
 '   learn to soar on wings of thought. And the student will
     surpass the teacher.
To Quote the immortal Socrates: "I drank what?" -Sullivan
_____________________________________________________________
 
Mail to: ...sun!portal!cup.portal.com!Sullivan or
         Sullivan@cup.portal.com
 )

mp1u+@andrew.cmu.edu (Michael Portuesi) (04/29/89)

witting@topaz.rutgers.edu (Paul K Willing) writes:
> 
> Now, if thats all there is to it, I ll go ahead and buy the Amiga
> instead of the Mac IIcx, but my understanding says its much more
> complicated than that.
> 

That statement make no sense.  A2000/2500 + flickerfixer + multisync
is still less than Mac IIcx + video board + Applecolor monitor, even
if you are getting the IIcx via student discount.

--
Michael Portuesi * Information Technology Center * Carnegie Mellon University
INET: mp1u+@andrew.cmu.edu * BITNET: mp1u+@andrew
UUCP: ...harvard!andrew.cmu.edu!mp1u+
MAIL: Carnegie Mellon University, P.O. Box 259, Pittsburgh, PA  15213

"Why do I live the way I do
 ain't it obvious I'm just a man like you"	--Boy George

hugh@censor.UUCP (Hugh D. Gamble) (04/29/89)

In article <12489472380034@osu-20.ircc.ohio-state.edu>, LARSEN-D@osu-20.ircc.ohio-state.edu (Poindexter) writes:
> 
> Multisync's don't flicker, that's what you get for your extra 2-300 bucks.

Woah boy!  A multi-sync has the ability to act as a higher frequency 
monitor (like a MAC II or PC VGA uses, approximately), but to use this
mode on an Amiga you need a flickerficker video interface board first.
What you get for your extra $ is what the "multi" means.  You can use it
with the normal Amiga video output *or* a higher frequency one.

If the original question was how to put the Amiga into 400 line interlace
mode, you go to preferences and set interlace to on, save it and reboot.
The only tricky bit is if you have a hard disk with SYS: assigned to it
that isn't SYS: when you first boot.  Then you also have to copy
SYS:devs/system-configuration to the devs directory on your boot disk.
Workbench 1.3 comes with a utility to do this if you boot from df0:.
-- 
Hugh D. Gamble (416) 581-4354 (wk), 267-6159 (hm) (Std. Disclaimers)
hugh@censor, kink!hugh@censor
# It may be true that no man is an island,
# but I make a darn good peninsula.

blgardne@esunix.UUCP (Blaine Gardner) (04/29/89)

From article <12489472380034@osu-20.ircc.ohio-state.edu>, by LARSEN-D@osu-20.ircc.ohio-state.edu (Poindexter):
> 
> Multisync's don't flicker, that's what you get for your extra 2-300 bucks.

Please, let's not spread misinformation!

Multisync monitors DO flicker.

All you get for your extra 2-300 bucks is the ability to spend another
5-700 bucks for MicroWay's flickerFixer board for your A2000. THEN you
have no flicker.

Of course the rumoured Enhanced Chip Set has a flicker free mode that
also requires a multisync montior. But the ECS is nowhere close to
shipping, and it's got severe color restrictions on the flicker-free
mode (4 colors from a palette of 64 at 640x400 as I remember).

	Blaine (Flicker Fixed and loving it) Gardner

-- 
Blaine Gardner @ Evans & Sutherland    580 Arapeen Drive, SLC, Utah 84108
Here: utah-cs!esunix!blgardne   {ucbvax,allegra,decvax}!decwrl!esunix!blgardne
"Nobody will ever need more than 64K."    "Nobody needs multitasking on a PC."

LARSEN-D@osu-20.ircc.ohio-state.edu (Poindexter) (04/29/89)

I was under the impression (mistaken?) that a multi-sync, by definition
would not flicker in interlaced mode.  I was at a local Amigoid type 
computer store and they had an NEC multi-sync running interlaced workbench
(standard colors) and there wasn't a trace of flicker.  Go figure.

dillon@HERMES.BERKELEY.EDU (Matt Dillon) (04/30/89)

:I was under the impression (mistaken?) that a multi-sync, by definition
:would not flicker in interlaced mode.  I was at a local Amigoid type 
:computer store and they had an NEC multi-sync running interlaced workbench
:(standard colors) and there wasn't a trace of flicker.  Go figure.

	It sounds like it was simply a high persistance monitor, or maybe
there was a de-interlacer installed in the Amiga.  A multi-sync simply
adjusts itself to the video rate of the computer, so a computer sending
interlace is displayed as interlace.  De-interlacing requires a frame buffer.

					-Matt

Sullivan@cup.portal.com (sullivan - segall) (04/30/89)

>Multisync's don't flicker, that's what you get for your extra 2-300 bucks.

Wrong.  Multisynch monitors (usually) use phosphors optimized for 1/60th of
a second.  They will flicker hideously when driven at a 1/30th refresh rate
(when they support it at all.)  Long persistence monitors don't flicker.
THAT's what you get for your extra 2-300 bucks....
 
What ever happened to the C-A long persistence monitor?  :-(

 
                           -Sullivan Segall
_____________________________________________________________
 
/V\  Sully set the example: to fly without moving.  We shall
 '   learn to soar on wings of thought. And the student will
     surpass the teacher.
To Quote the immortal Socrates: "I drank what?" -Sullivan
_____________________________________________________________
 
Mail to: ...sun!portal!cup.portal.com!Sullivan or
         Sullivan@cup.portal.com
 

thomas@cbmvax.UUCP (Dave Thomas QA) (05/01/89)

In article <EYJwQny00Vsf44E0V2@andrew.cmu.edu> mp1u+@andrew.cmu.edu (Michael Portuesi) writes:
> > *Excerpts from ext.nn.comp.sys.amiga: 27-Apr-89 Re: How do you turn on flic..*
> > *Poindexter@osu-20.ircc.o (76)*
> 
> > Multisync's don't flicker, that's what you get for your extra 2-300 bucks.
> 
> not true, unless you have an A2000 + flickerfixer.  they might flicker less than
> the 1080/1084/2002, but they still flicker.

   Actually, they might flicker more.  Many multisync's are not designed to
handle an interlaced signal.  When they try to display one, the even and odd
scan lines are not always put in the same spot.  The end result is that text
becomes almost impossible to read and a headache is guarenteed.  The moral:
try a multisync before you buy; if you can't do that then make sure the 
dealer won't hassle you if you return it.

         Dave
-- 
Dave Thomas, Commodore Amiga Test Engineering
UUCP  ...{allegra,rutgers}!cbmvax!thomas

blgardne@esunix.UUCP (Blaine Gardner) (05/03/89)

From article <6718@cbmvax.UUCP>, by thomas@cbmvax.UUCP (Dave Thomas QA):
>> > Multisync's don't flicker, that's what you get for your extra 2-300 bucks.
 
>    Actually, they might flicker more.  Many multisync's are not designed to
> handle an interlaced signal.  When they try to display one, the even and odd
> scan lines are not always put in the same spot.  The end result is that text
> becomes almost impossible to read and a headache is guarenteed.  The moral:
> try a multisync before you buy; if you can't do that then make sure the 
> dealer won't hassle you if you return it.

Very true! I've got the original NEC Multisync (JC-1401P3A) and in
interlace it is impossible to see anything smaller than two pixels high
clearly. This is because both the odd and even scan lines are being
displayed on the same place on the screen. The black lines between scan
lines on a 200 line screen are still there, and the image on the odd
lines is overwritten by the image on the even lines.

If you think interlace flicker looks bad, you should see this!

Others have reported that the same model number works fine in interlace,
so either NEC fixed the monitor, or there's some arcane cabling trick I
haven't discovered.

My solution was to throw good money after bad and buy a flickerFixer. :-)

I don't think the flickerFixer is really worth the high price, but on
the other hand if you offered me what I paid for it, I'd keep the thing.
If you haven't seen a flickerFixed 704x470 WorkBench screen with a
Tapestry image in color 0, you don't know how nice this machine can
look.
-- 
Blaine Gardner @ Evans & Sutherland    580 Arapeen Drive, SLC, Utah 84108
Here: utah-cs!esunix!blgardne   {ucbvax,allegra,decvax}!decwrl!esunix!blgardne
"Nobody will ever need more than 64K."    "Nobody needs multitasking on a PC."

c60c-1ea@web-3f.berkeley.edu (Yen Yuanchi Hsieh) (05/05/89)

In article <1307@esunix.UUCP> blgardne@esunix.UUCP (Blaine Gardner) writes:
>Very true! I've got the original NEC Multisync (JC-1401P3A) and in
>interlace it is impossible to see anything smaller than two pixels high
>clearly. This is because both the odd and even scan lines are being
>displayed on the same place on the screen. The black lines between scan
>lines on a 200 line screen are still there, and the image on the odd
>lines is overwritten by the image on the even lines.
>
>If you think interlace flicker looks bad, you should see this!

Well, I had the same problem with my Sony monitor.  As it cropped up
some time after I got my computer, I thought it was my computer's fault,
and I took it into to get it repaired.  Of course, there was nothing wrong
with it.  Turns out that the Vertical Sync (or was it the Horizontal?, can't
remember, and I always get the two confused...) was misadjusted, and 
twiddling with that knob fixed the problem. 

>Others have reported that the same model number works fine in interlace,
>so either NEC fixed the monitor, or there's some arcane cabling trick I
>haven't discovered.

The above could explain it -- or your monitor may be syncing bad with the
original signal.

>My solution was to throw good money after bad and buy a flickerFixer. :-)

Of course, I've got a 500, so I'm not able to do this, sigh...
The whole idea was to wait for the A3000 to come out -- I figure it might
be available by the time I get out of school (2 more years).


>-- 
>Blaine Gardner @ Evans & Sutherland    580 Arapeen Drive, SLC, Utah 84108
>Here: utah-cs!esunix!blgardne   {ucbvax,allegra,decvax}!decwrl!esunix!blgardne
>"Nobody will ever need more than 64K."    "Nobody needs multitasking on a PC."

---
David Navas c60c-1ea@WEB.Berkeley.Edu
Ideas?  What ideas?  If I had any idea I was going
to have an idea I wouldn't have posted this nonsense.