From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267424AbUHXVet (ORCPT ); Tue, 24 Aug 2004 17:34:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S268332AbUHXVet (ORCPT ); Tue, 24 Aug 2004 17:34:49 -0400 Received: from damned.travellingkiwi.com ([81.6.239.220]:21604 "EHLO ballbreaker.travellingkiwi.com") by vger.kernel.org with ESMTP id S268347AbUHXVad (ORCPT ); Tue, 24 Aug 2004 17:30:33 -0400 Message-ID: <412BB372.9000009@travellingkiwi.com> Date: Tue, 24 Aug 2004 22:30:26 +0100 From: Hamie User-Agent: Mozilla Thunderbird 0.7.1 (X11/20040715) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Kyle Moffett Cc: Jonathan Bastien-Filiatrault , linux-kernel , Wakko Warner , "David N. Welton" , Lee Revell , James Courtier-Dutton Subject: Re: Linux Incompatibility List References: <87r7q0th2n.fsf@dedasys.com> <20040821201632.GA7622@digitasaru.net> <20040821202058.GA9218@animx.eu.org> <1093120274.854.145.camel@krustophenia.net> <41282F4C.9060305@dastyle.net> <4127FD5A.90605@superbug.demon.co.uk> <41283EDA.6080501@dastyle.net> In-Reply-To: X-Enigmail-Version: 0.84.1.0 X-Enigmail-Supports: pgp-inline, pgp-mime Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Kyle Moffett wrote: > On Aug 22, 2004, at 02:36, Jonathan Bastien-Filiatrault wrote: > >> My dad had a thing like that(quick reference card) for an old >> motorola 6800(not 68000) processor. It only had 2 8-bit general >> purpose registers if I remember correctly. Doesn't even begin to >> compare with modern ppc processors. > > > Hey! I built a primitive computer from one of those in a > microprocessor class a year ago. 2 8-bit registers, 8-bit data-bus > and 16-bit address bus. There were two interrupt pins, IRQ and NMI, > and a simple condition code register. The CPU clock is the same as > the bus clock. What fun!!! > Here's where I feel my age... 6502 with ONE (That's 1) general purpose register (Called the accumulator)... Plus a couple of others used mainly for offsets (X & Y if I remember correctly)... No 16-bit maths... All 8-bit. (As were the registers). Boy the 6809 was easy to program after that sucker... The 6809 (basically an extension of the original 6800) had 2x 8-bit registers IIRC, that you could actually treat as a single 16-bit register as well (i.e. multiply one 8bit by the seocnd & read the result from the '16-bit' register... The assember language on the 6800 series was way better than the 6502 (And the 6510). but I digress... Even IBM were good with open source. I think I still have an IBM PC tech reference around here with the complete source code listing (In x86 assembler) of the original IBM PC Bios. Now that made for innovation... Open hardware & software. Heck most of these companies need a good reminder that if they hadn't had a leg up fro Open computing in the early 80's they wouldn't be here today. H