Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!cbmvax!andy From: andy@cbmvax.commodore.com (Andy Finkel) Newsgroups: comp.sys.amiga Subject: Re: Z machine et al Message-ID: <17282@cbmvax.commodore.com> Date: 9 Jan 91 17:42:33 GMT References: <10.278AB99D@weyr.FIDONET.ORG> Reply-To: andy@cbmvax.commodore.com (Andy Finkel) Organization: Commodore, West Chester, PA Lines: 34 In article <10.278AB99D@weyr.FIDONET.ORG> David.Plummer@f70.n140.z1.FIDONET.ORG (David Plummer) writes: >LN> Well, you could flip a bit and get a sudden speed increase, an order >LN> of magnitude or so. Too bad they didn't flip that bit at the factory. >LN> If you followed the output vector ($ffe4?) you could notice how it >LN> busywaited for the CRT to finnish drawing the current frame before >LN> updating screen RAM, just to avoid some very minor flicker near the >LN> screen position updated. It was not the only Microsoft mis-feature in >LN> those ROMs, I can assure you! I was always wondering why someone at >LN> CBM didn't optimize things. Any CBM people from that time still >LN> around? Now is your chance to explain yourself! ;-) >LN> >LN> >LN> Kent, the man from xanth. >LN> >LN> It wasn't minor flickering...it was major flickering. In fact, I did a screen hack on the PET that use it to produce a snow storm in a demo program. I seem to remember that the video controller was later updated to sync updates to screen blank, and the software fix was removed. (my snow storm vanished; and I had to explain to a bunch of people how it was supposed to look) andy -- andy finkel {uunet|rutgers|amiga}!cbmvax!andy Commodore-Amiga, Inc. "And Amiga has not forgot the retailer." Any expressed opinions are mine; but feel free to share. I disclaim all responsibilities, all shapes, all sizes, all colors.