Xref: utzoo alt.folklore.computers:7588 comp.unix.internals:1183 comp.misc:10687 Path: utzoo!utgpu!cs.utexas.edu!usc!srhqla!demott!kdq From: kdq@demott.COM (Kevin D. Quitt) Newsgroups: alt.folklore.computers,comp.unix.internals,comp.misc Subject: Re: Hardware Architectures and I/O (was: Re: Jargon file...) **FLAME!!** Message-ID: <1058@demott.COM> Date: 2 Dec 90 21:59:39 GMT References: <1990Dec2.154303.17105@eddie.mit.edu> Reply-To: kdq@demott.COM (Kevin D. Quitt) Followup-To: alt.folklore.computers Organization: DeMott Electronics Co., Van Nuys CA Lines: 34 In article <1990Dec2.154303.17105@eddie.mit.edu> rs@eddie.mit.edu (Robert E. Seastrom) writes: >In article pst@ir.Stanford.EDU (Paul Traina) writes: >> >>Back when there were REAL(tm) computers like 780, a lot of time and >>energy went into designing efficient I/O from the CPU bus to the >>electrons going to the disk or tty. >> > >Damn right, but even the 780 was a step down. Get your KL-10 >documentation set out and read about *them*. Front-end PDP-11s that >did Tops-20's command completion. Seperate I/O and memory buses. >8-ported (that's eight, son) memory that talked to the I/O front-end >machines for *real* DMA, not cycle stealing! Which in turn was a step down from the Sigmas, with 12 ported memory. (lots of little wires in those donuts). Every major device got its own port - the CPU was just another device. (You could plug a slave CPU into the bus while the system was running; after its self-test, the system would "find" it and start assigning it tasks). Lot of nice touches on that machine, like a line printer (not the driver) that kept track of hills and valleys. The CPU couldn't have been as powerful as a 68030 or 486, but it'd do real-time flight simulation without a hitch, or timeshare more than 90 users before it started to get annoying. -- _ Kevin D. Quitt demott!kdq kdq@demott.com DeMott Electronics Co. 14707 Keswick St. Van Nuys, CA 91405-1266 VOICE (818) 988-4975 FAX (818) 997-1190 MODEM (818) 997-4496 PEP last 96.37% of all statistics are made up. Brought to you by Super Global Mega Corp .com