Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!mips!apple!motcsd!starnet!sschaem From: sschaem@starnet.uucp (Stephan Schaem) Newsgroups: comp.sys.amiga.advocacy Subject: Re: Blitter vs. 040 (was: Computer Architecture question Message-ID: <1991May17.173402.24107@starnet.uucp> Date: 17 May 91 17:34:02 GMT References: <1991May15.125954.1993@NCoast.ORG> <1991May15.213917.11992@ugle.unit.no> <1991May16.043705.6698@NCoast.ORG> <1991May16.203434.4709@ugle.unit.no> Organization: Starnet-Public Access UNIX-Los Altos,CA 415-949-3133, login:info Lines: 23 And again! When you have 16 color the machine dont go 2 time slower than with 2 bitplane... You have twice has mutch data to work with AND you bus access during display is reduce to ZERO! 'No wonder its slow'.And doing it with the processor is a major error (In that case). Because You will defenectly NOT init a scroll during any display time. ( because the CPU will be monopolize by bus wait in betwen HBG). So you have to syncronize your 68030 with the BOF, and do the work then. The Blitter will take 'ALL' the cycle available during the display time! AND you can do you calculation with the 68030 whenever!... Scrolling with the main (And only:-) CPU in that case is a MAJOR error. And you only have 64 instruction in your cache (No 68040 in my A3000 yet:-) to fit your blit function. Already now the Blitter is a BIG+ and if it goes 32bit or faster ther NO question to ask about its usage in a multi bus system! Stephan.