Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!apple!sun-barr!newstop!sun!cmcmanis
From: cmcmanis@sun.Eng.Sun.COM (Chuck McManis)
Newsgroups: comp.sys.amiga.tech
Subject: Re: V1.4+ScrollRaster + ECS
Message-ID: <124439@sun.Eng.Sun.COM>
Date: 11 Sep 89 18:50:02 GMT
References: <4463@cps3xx.UUCP>
Reply-To: cmcmanis@sun.UUCP (Chuck McManis)
Organization: Sun Microsystems, Mountain View
Lines: 44

In article <4463@cps3xx.UUCP> porkka@frith.egr.msu.edu () writes:
->Two simple questions to those in the know:
->  1: I have asked this twice before, but I have not seen it
->     answered as yet.
->     Will ScrollRaster() be fixed in respect to SIMPLE_REFRESH???????
->     A simple yes/no answer from CATS would be nice.

I guess I must have missed the original problem. What is broken about it?
I've used it on S_R windows (and hence SIMPLE layers) and it seemed to 
work as advertised. (It flashes of course when you have lots of bit planes
but that isn't ScrollRaster's fault per se.)

-> 2: The ECS I have heard will allow for 400 line display modes
->    non-interlaced. THis is fine if you have a multisync.
->    What happens if you have a standard NTSC compatible monitor,
->    and some whizbang software opens up a 400 lines non-interlace
->    screen??
->
->    I have heard that if you do this you will actually destroy or
->    damage many monitors.
->    If so, there should be a hardware toggle switch to prevent
->    such displays from being used if you only have a regular
->    monitor, no?

Actually, it won't hurt your monitor. But the picture will look weird.
The problem with damaging monitors comes from setting up a scan rate that
is *much* faster than the monitor is designed for. This causes lots of 
Hsyncs to be sent to the monitor and keeps the Horizontal driver transistor
on more often than it should be. This has two effects:
	1) The H Transistor is designed for a small duty cycle, lots of 
	   hsyncs cause it to be "on" more often and that can overheat it.
	   After overheating it can burn out and leave you with a dead monitor.
	2) The rapid fire hsyncs are what are feeding the flyback transformer
	   in some monitors, and by changing the frequency and "shape" of the
	   signal you can cause the flyback to burn out as well. 

Now all the ECS does is double the scan rate. This will stress your monitor
but it isn't enough to damage it.


-- 
--Chuck McManis
uucp: {anywhere}!sun!cmcmanis   BIX: cmcmanis  ARPAnet: cmcmanis@sun.com
These opinions are my own and no one elses. But you knew that, didn't you.