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- Path: altair.krl.caltech.edu!shoppa
- From: shoppa@altair.krl.caltech.edu (Tim Shoppa)
- Newsgroups: comp.sys.amiga.misc,comp.sys.amiga.advocacy,alt.folklore.computers
- Subject: Re: First multitasking OS for home computers
- Date: 17 Jan 1996 20:53:26 GMT
- Organization: Kellogg Radiation Lab, Caltech
- Message-ID: <4djnk6$l88@gap.cco.caltech.edu>
- References: <4cmd5g$7h0@coranto.ucs.mun.ca> <4cpcnc$hmg@sue.cc.uregina.ca> <30f9330f.13824238@news.embratel.net.br>
- NNTP-Posting-Host: altair.krl.caltech.edu
-
- In article <30f9330f.13824238@news.embratel.net.br>,
- Evandro Menezes <emenezes@embratel.net.br> wrote:
- >bayko@ARISTOTLE.CS.UREGINA.CA (John Bayko) wrote:
- >
- >> But if you stretch the definition of both 'multitasking' and
- >>'Operating System', then the ZX-81 qualifies, I think - the Z-80 both
- >>drove the display, and ran programs in the retrace interval. And it
- >>was only $150US (actually, it did this *because* it was only $150US -
- >>it only had 4 ICs in the entire thing - Z-80, RAM chip, ROM chip, and
- >>glue logic).
- >
- >Yes, that can be said. After all, display refreshing was a background (or
- >foreground?) task handled by the CPU.
-
- This scheme wasn't invented by Clive Sinclair, though he certainly
- used it quite effectively. The first reference I know
- of to this is in _The Cheap Video Cookbook_, by (I believe) Don
- Lancaster.
-
- If you want to see an excellent example of "home" multitasking,
- check out any Atari 2600... but then we're back to the question
- of what multitasking really is. Or, for that matter, what a
- "home computer" is. To push the two ends of the spectrum:
-
- 1. Is a DEC LSI-11/03 or (equivalently) a Heath
- H11 running RSX-11S in my living room a home computer? Or
- a PDP-8/E running a homebrew timesharing system?
-
- 2. Or is the timer on a microprocessor controlled microwave oven
- a home computer?
-
- Tim. (Typing this on his Televison-Typewriter!)
-