Re: 14MHz 65816??

[nathan@visi.com (Nathan Mates)]

In article <4v8hso$rdi@news.vanderbilt.edu>,
Tilghman Lesher <lesherjt@vuse.vanderbilt.edu> wrote:
>Nathan Mates (nathan@visi.com) wrote:
>: Tilghman Lesher <lesherjt@vuse.vanderbilt.edu> wrote:
>: >Nope; can't do this.  Remember that the regular 2.8 MHz chip slows down
>: >to 2.6 MHz because of the 1 MHz bus speed.

>:    Argh. No. Wrong. The processor internally runs at 2.8Mhz, but due
>: to ram refresh cycles, the effective speed is about 2.6Mhz. Things are

>Whatever.  It's called an effective abbreviation where an explanation
>works for simple users, even if the explanation is not technically
>correct.  Such is used by many people (try the Perl instruction booklets)
>to try to explain complex ideas in simple language without confusing
>learners.

   To hell with simplicity, TELL THE TRUTH! Wrong ideas have a BAD
habit of becoming accepted. ["ram refresh cycles" is just as much
technobabble to the illiterate as is "1Mhz Bus speed", and it's wrong.]

>Your messages seem to disappear.  Does your newsreader cancel articles
>on the same thread when you post followups?  If so, maybe you need another
>newsreader which doesn't do this.

   Not at all. My posts are still available here on visi.com where I
wrote them, as well as on other sites where I checked, such as
Caltech. Problems with posts disappearing is a _LOCAL_ problem, one
that you need to talk to your sysadmins about. I'd bet that they have
the expire set to only a few days to save disk space.

   For the record, I use trn 3.6 for unix, which does no such
craziness unless you specifically tell it to, and I've been using
[t]rn for 4 years now, and am quite aware of how to post properly. I
also understand how usenet works-- each site has a news server which
holds new articles and throws them out some time after arrival. This
expiration is site dependent, and set by the administrator _of that
site_.

   When posting, you can set the "Expires:" field in the posting
header manually (not all newsreaders allow that, which is one reason
why they suck) to give hints as to how long you want the post to stay
around for, but that is not guaranteed to work. My posts go out with
the default blank "Expires" header, which is translated as "Expire
when your local configuration says to do so"

>:    As I said earlier in this thread, you'd have to redesign the
>: motherboard from scratch to be able to plug in a faster 65816 and
>: hope it ran. And the odds of that happening are slim and none.

>You don't think a motherboard could be modified to do it?  You have a
>very low opinion of the abilities of EE's.  YES, IT WOULD BE DIFFICULT.
>YES, IT PROBABLY WOULDN'T WORK ON THE FIRST TRY.  But that's a far
>cry from saying that it cannot be done.

   No, I've got a very low opinion of those who think it'd actually be
easier to modify the motherboard than to buy an accelerator. Modifying
the existing motherboard to 1) leave all parts that require 2.8Mhz on
a 2.8Mhz signal 2) Provide a faster speed to the processor slot and
interface the faster processor to the 2.8/1Mhz bus. 3) Realize that
most of the chips on the GS motherboard (including a whole bunch of
apple proprietary ones, which you can't buy off the shelf) are rated
to 4Mhz max, so you'd either have to redesign those chips as well
or only be able to run stuff at 4Mhz.

   This would end up with a lot of extra chips, miniboards, and other
things embedded in the existing motherboard to provide the
interfacing, oscillators, etc. You do not get extra functionality
without adding chips and parts, unless you're from the school of
voodoo EE.

   As I said, REDESIGN THE MOTHERBOARD FROM SCRATCH if you want more
speed with out an accelerator card. Only the truely boneheaded among
the EEs would set out on the most difficult of paths when other paths
(like designing yet another GS accelerator) are far easier. Either
that or you're desperate for a thesis project in the "crazy kludge
without any chance of marketability"

   Actually, I don't think it'd be that difficult after all. Find a
tall building, say 10 stories. Put GS at base, with case off. Go to
top, with accelerator card in hand. Aim well. Repeat until motherboard
and/or accelerator card are in pieces. Solder at random. 

Nathan Mates

--
<*> Nathan Mates http://www.visi.com/~nathan/      <*>
# What are the facts? Again and again and again-- what are the _facts_?
# Shun wishful thinking, avoid opinion, care not what the neighbors
# think-- what are the facts, and to how many decimal places?  -R.A. Heinlein