Date: Thu, 9 Aug 2001 23:50:15 +0100 From: j mckitrick <jcm@FreeBSD-uk.eu.org> To: Mike Meyer <mwm@mired.org> Cc: David Scheidt <dscheidt@enteract.com>, Dag-Erling Smorgrav <des@ofug.org>, Greg Lehey <grog@FreeBSD.ORG>, tlambert2@mindspring.com, freebsd-chat@FreeBSD.ORG Subject: Re: How did the MSFT monopoly start? Message-ID: <20010809235015.A95638@dogma.freebsd-uk.eu.org> In-Reply-To: <15218.62861.955183.430680@guru.mired.org>; from mwm@mired.org on Thu, Aug 09, 2001 at 03:41:49PM -0500 References: <xzpelql4ms3.fsf@flood.ping.uio.no> <Pine.BSF.4.32L2.0108091238510.70995-100000@shell-2.enteract.com> <15218.62861.955183.430680@guru.mired.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Thu, Aug 09, 2001 at 03:41:49PM -0500, Mike Meyer wrote: | David Scheidt <dscheidt@enteract.com> types: | > On 9 Aug 2001, Dag-Erling Smorgrav wrote: | > :Mike Meyer <mwm@mired.org> writes: | > :> address space was 32 bits - the top 8 got thrown away when you left | > :> the CPU - and it didn't have special registers for addressing, so the | > :> general registers had to be 32 bits wide and it had to have those 32 | > :> bit operations. | > :AFAIK, the 68k has separate data and address registers (d0-d7 and | > :a0-a7 respectively) | > You can use them all as general purpose registers. There might be some | > restrictions, but I can't remember any. It's been quite a while though. Of | > course, an OS will place restrictions on what registers you can use. | | No, DES is right. Data registers could be used for pretty much | anything but the source of an address. They could be an offset from an | address, including an address of 0, which pretty much made that | immaterial. Address registers - besides being an address - could only | be loaded, added, subtracted and moved. The stack pointer - always(?) | a7 - also got tweaked by stack instructions. | | > Why does 68040 still scream "Oh, fast!" to me, and 1.4 GHz Athlon make me go | > "So?" | | Because you know the 1.4GHz Athlon is going into a system with a | system bus most of an order of magnitude slower than 1.4GHz? OK, that's enough. You are making me want to take my Amiga out of storage. :-) jm -- "Investigators have discovered the cause of the TWA 800 explosion was a frayed wire. The wire became frayed when it was struck by a missile." To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-chat" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20010809235015.A95638>