Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10 5/3/83; site ucbcad.UUCP Path: utzoo!linus!philabs!cmcl2!floyd!vax135!cornell!uw-beaver!tektronix!ucbcad!ucbesvax.turner From: ucbesvax.turner@ucbcad.UUCP Newsgroups: net.arch Subject: uP architecture - (nf) Message-ID: <189@ucbcad.UUCP> Date: Thu, 30-Jun-83 12:24:47 EDT Article-I.D.: ucbcad.189 Posted: Thu Jun 30 12:24:47 1983 Date-Received: Fri, 1-Jul-83 22:24:42 EDT Sender: notes@ucbcad.UUCP Organization: UC Berkeley, CAD Group Lines: 28 #N:ucbesvax:12800003:000:1097 ucbesvax!turner Jun 30 01:18:00 1983 Can anyone venture a theory as to why many microprocessor architectures are so terrible? I am referring here to 8080 and its derivatives. It's hard for me to believe that there just weren't good architects around at the time, or that the medium was the main constraint. I am told that Datapoint machines are TTL implementations of a slight variant of 8080. And that the 8080 was originally a design commissioned by the Japanese phone company, who later rejected it as too slow for their purposes. These stories could be apocryphal. Why wasn't the first uP a Nova? Or perhaps a PDP-11 subset? Or at least something *good*? The 6800 was a reasonably intelligent design, since it as much as said: "forget speed, use stacks", and provide (voila!) a stack-oriented architecture. The much-later 6809 is, to my mind, the first really good 8-bit machine to appear, and seems to take a position midway between the 6800 and the 68000. Finally, has anyone heard of the 1802, which I have been told is a very slow but architecturally elegant CMOS uP? Michael Turner ucbvax!ucbesvax.turner