![](/i/fill.gif) |
![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
On 5/11/2010 7:41 AM, Invisible wrote:
>
> You know that there are people who do scientific experiments *about*
> computer programs, right? ;-)
>
Yeah :)
Actually, in the vein of computer science: For the fun of it I'm
designing CPU from scratch. I plan to build it with TTL gates after I
have the design complete and have vetted it through simulation. I have
the ALU designed. (Fairly simple, it can add, perform bitwise logic and
shift, as well as calculate the twos complement. Other operations will
take multiple cycles) I also have most of the control logic put
together, but I need to make some changes to ensure an ALU instruction
can occur within 2 cycles (One to latch the ALU result, one to store the
result in the accumulator)
Eventually, I want to take a simplified version of that design and
create a CPU entirely out of relays. Obviously, I'd need keep the design
as simple as possible, but still functional to keep the relay count
down. Something about a bit stack of clacking relays with blinking
lights really appeals to me. That machine will likely still have IC
memory, though, but the registers will be relay latches.
One consideration for the relay version is that the machine should be
able to halt and only resume processing on an interrupt. So, ideally,
you'd give it inputs, issue a command, and send it clacking away to get
a result.
It's fun stuff, and occupies a good deal of time. Also a great way to
learn HOW a computer like the one you're sitting at actually works. e.g.
how each instruction of machine code does what it does, etc...
The TTL version should be fun, too. I plan to have lots of LEDs to show
what's happening inside the machine.
--
~Mike
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
On 5/11/2010 7:51 AM, Invisible wrote:
>>> Strangely enough, Einstein himself had a kind of "pop star" status at
>>> his time. Science was considered sort of "sexy" back then.
>>
>> Why can't we get back to putting people who actually contribute to the
>> better understanding of the world around us back on the pedestal
>> instead of placing vacuous celebrities and sports stars on a pedestal?
>
> There's more of the latter?
Definitely true....
> They're cheaper to have around?
Have you seen their salaries?
> It's easier for the general public to comprehend a man kicking a hollow
> lump of cow hide than the concept that time and space are subjective?
But, in my mind, infinitely more interesting than watching someone kick
a hollow lump of cow hide around.
--
~Mike
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
>> They're cheaper to have around?
>
> Have you seen their salaries?
Do you know what the likes of Einstein command? ;-)
>> It's easier for the general public to comprehend a man kicking a hollow
>> lump of cow hide than the concept that time and space are subjective?
>
> But, in my mind, infinitely more interesting than watching someone kick
> a hollow lump of cow hide around.
FWIW, I agree...
You've got to admit, though, that mathematics and science are not
spectator sports. It can be very interesting to do yourself, but
watching the greats of the day doing it isn't particularly interesting.
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
>> You know that there are people who do scientific experiments *about*
>> computer programs, right? ;-)
>
> Yeah :)
OK, good. :-)
> Actually, in the vein of computer science: For the fun of it I'm
> designing CPU from scratch. I plan to build it with TTL gates after I
> have the design complete and have vetted it through simulation.
...this sounds so much like my life approximately 15 years ago...
> Eventually, I want to take a simplified version of that design and
> create a CPU entirely out of relays.
> Something about a bit stack of clacking relays with blinking
> lights really appeals to me.
Hmm, interesting.
Perhaps you would have enjoyed a visit to Stoney Stratford telephone
exchange. It's a sprawling building, filled with rack after rack after
rack of cases, each case filled with dozens of relays. And they're not
in cases or anything, just "naked", so you can see (and if you desire,
move) the working components. There is also several tonnes of wire
overhead feeding this equipment. And all of it is as silent as death.
It's like a museum or something.
(Just down the corridor there's a small broom cupboard. This is the
*real* telephone exchange, alive and operational. It's really just a few
lasers and some circuit boards. But mess with it and you'll have just
taken 15,000 customers offline!)
Myself, I visualised a computer made of pressurised water fed through a
series of simple mechanical valves. Sadly, I fear that for reliable
operation, you would need inside water pressure. And if you wanted a
clock speed of more than about 0.02 Hz, you would have to use steel
piping and pyrotechnics to sustain the necessary pressure! It would be a
very "kinetic" experience though.
> It's fun stuff, and occupies a good deal of time. Also a great way to
> learn HOW a computer like the one you're sitting at actually works. e.g.
> how each instruction of machine code does what it does, etc...
Yeah. I've written about it before now. (As I say, a computer is a layer
cake though. Try to explain it and laymen quickly get lost in the layers
of abstraction upon abstraction needed to perform even the most trivial
task.)
Also... when I tried to build my own machine out of 7400s, I quickly
discovered that the gates don't appear to function as their truth table
indicates that they should. (!) I also looked into playing with FPGAs,
but the cost is prohibitive. (And, knowing me, I'd just make something
that doesn't even work, and then spend months trying to find out why!)
Plus, Xilinix (?) have a free simulation tool available, and it's just
painful to use. I dred to think what actually synthesizing with it would
be like...
> The TTL version should be fun, too. I plan to have lots of LEDs to show
> what's happening inside the machine.
In solomn truth, it's probably simpler and easier to code a small peice
of JavaScript that controls a little Flash animation on a computer
screen. But there's something impressive about being able to pick up a
physical object in your hands and see that there really are no tricks...
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
On Tue, 11 May 2010 09:11:59 +0100, Invisible wrote:
>>> Ask some random person "who is Einstein?" and they'll instantly know
>>> he was a world-famous scientist.
>>>
>>> Ask somebody who Richard Dawkins is and see how many of them actually
>>> have any clue. (I've only heard of him because I read the book he
>>> wrote.)
>>
>> Well, again, he's written several, so which did you read?
>
> Uh... I can't actually remember the title now. Let me go check...
>
> ...OK, the copy on his website has different cover art [sigh], but I
> believe it was Climbing Mount Improbable.
OK, so that's one book. The more important works that he wrote had to do
with genetics.
>> But in my circles, Richard Dawkins is quite well know. So's Jane
>> Goodall, for that matter.
>
> My point being that you don't need to be in any particular "circles" to
> know who Einstein or Newton is.
Well, you assume everyone has heard of them. There's probably some guy
living in a little village in a remote part of Africa who's never heard
of either of them.
> Even very small children have heard the
> tale of how Newton was hit on the head by an apple. (I wonder if that
> myth actually happened?)
It didn't; there was a bit on an episode of QI this series that talked
about the myth.
> Everybody has heard of Archimedies, even if they're not sure exactly
> what he did.
>
> Unfortunately, there's nobody alive today of quite the same stature -
> except perhaps Steven Hawking.
Again, Jane Goodall probably fits that bill. If we counted people who
have lived in our lifetimes, Carl Sagan. Vint Cerf, Sir Tim Berners-Lee,
both of whom I previously mentioned, are also quite well known.
Jim
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
Mike Raiford wrote:
> On 5/10/2010 3:12 AM, Invisible wrote:
>>> Or Carl Sagan, for that matter.
>>
>> Who?
>>
>
> Inventor of the communications satellite, physicist, cosmologist ... and
> sci-fi writer....
Also the narrator of Cosmos. I don't know anyone who didn't watch Cosmos.
--
Darren New, San Diego CA, USA (PST)
Ada - the programming language trying to avoid
you literally shooting yourself in the foot.
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
>> Uh... I can't actually remember the title now. Let me go check...
>>
>> ...OK, the copy on his website has different cover art [sigh], but I
>> believe it was Climbing Mount Improbable.
>
> OK, so that's one book. The more important works that he wrote had to do
> with genetics.
Yeah, this one had to do with evolution and so forth. It made multiple
references to The Blind Watchmaker, but I haven't read that.
>>> But in my circles, Richard Dawkins is quite well know. So's Jane
>>> Goodall, for that matter.
>> My point being that you don't need to be in any particular "circles" to
>> know who Einstein or Newton is.
>
> Well, you assume everyone has heard of them. There's probably some guy
> living in a little village in a remote part of Africa who's never heard
> of either of them.
I meant in general Western culture. People have written books and made
films about Einstein, Newton and the like. They're that all known that
"almost everybody" knows of them. I doubt too many people know who, say,
William Harvey.
>> Even very small children have heard the
>> tale of how Newton was hit on the head by an apple. (I wonder if that
>> myth actually happened?)
>
> It didn't; there was a bit on an episode of QI this series that talked
> about the myth.
What a surprise...
(The next question, of course, becomes "who invented this myth?")
>> Everybody has heard of Archimedies, even if they're not sure exactly
>> what he did.
>>
>> Unfortunately, there's nobody alive today of quite the same stature -
>> except perhaps Steven Hawking.
>
> Again, Jane Goodall probably fits that bill. If we counted people who
> have lived in our lifetimes, Carl Sagan. Vint Cerf, Sir Tim Berners-Lee,
> both of whom I previously mentioned, are also quite well known.
I would refute that... Perhaps I need to do a straw poll when I go down
the pub tonight? (Although I can't *pronounce* most of those names, so...)
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
Darren New wrote:
> Also the narrator of Cosmos. I don't know anyone who didn't watch Cosmos.
Apparently you don't know me then.
What's Cosmos then?
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
On 11-5-2010 14:36, Mike Raiford wrote:
> On 5/8/2010 5:40 PM, andrel wrote:
>
>>> Ah, but no - that just shows that the dude had a sense of humour.
>>> (Something which apparently nobody today expects scientists to have...)
>>>
>> Oh come on, I am I scientist too...
>> Ok, I see what you mean.
>
> What does make one a scientist?
That is probably round three or four for Darren. ;)
> Someone once told me with all of the
> things I do I should be a scientist.
>
> ... My thought was, "By experimenting with the world around me, and
> observing the effects ... doesn't that by definition make me one?"
>
> Then again, I'm not a professor, I have no college degree, and my career
> choice is "Code Monkey" so, does that exclude me from being a scientist?
>
> Do I need a career as a researcher to consider myself a scientist?
No. Until quite recently most scientists had a day time job too. Very
few could live from just doing science.
> You see. That simple statement she made threw me into an existential
> crisis ...
>
> I'm socially awkward... but, that only makes me a nerd, not a scientist :)
The two are not mutual exclusive.
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
On Tue, 11 May 2010 19:05:36 +0100, Orchid XP v8 wrote:
>>> Uh... I can't actually remember the title now. Let me go check...
>>>
>>> ...OK, the copy on his website has different cover art [sigh], but I
>>> believe it was Climbing Mount Improbable.
>>
>> OK, so that's one book. The more important works that he wrote had to
>> do with genetics.
>
> Yeah, this one had to do with evolution and so forth. It made multiple
> references to The Blind Watchmaker, but I haven't read that.
So then you do know what he's done. ;-)
>>>> But in my circles, Richard Dawkins is quite well know. So's Jane
>>>> Goodall, for that matter.
>>> My point being that you don't need to be in any particular "circles"
>>> to know who Einstein or Newton is.
>>
>> Well, you assume everyone has heard of them. There's probably some guy
>> living in a little village in a remote part of Africa who's never heard
>> of either of them.
>
> I meant in general Western culture. People have written books and made
> films about Einstein, Newton and the like. They're that all known that
> "almost everybody" knows of them. I doubt too many people know who, say,
> William Harvey.
>
>>> Even very small children have heard the tale of how Newton was hit on
>>> the head by an apple. (I wonder if that myth actually happened?)
>>
>> It didn't; there was a bit on an episode of QI this series that talked
>> about the myth.
>
> What a surprise...
>
> (The next question, of course, becomes "who invented this myth?")
GIYF - a hit that I got returned:
http://physics.about.com/od/classicalmechanics/a/gravity.htm
>>> Everybody has heard of Archimedies, even if they're not sure exactly
>>> what he did.
>>>
>>> Unfortunately, there's nobody alive today of quite the same stature -
>>> except perhaps Steven Hawking.
>>
>> Again, Jane Goodall probably fits that bill. If we counted people who
>> have lived in our lifetimes, Carl Sagan. Vint Cerf, Sir Tim
>> Berners-Lee, both of whom I previously mentioned, are also quite well
>> known.
>
> I would refute that... Perhaps I need to do a straw poll when I go down
> the pub tonight? (Although I can't *pronounce* most of those names,
> so...)
You might refute it, a straw poll might be a start, but a poll of 20
people isn't a particularly statistically valid poll.
As for pronunciation, I'm guessing Vint Cerf is the one you are having
trouble with - I gave a clue, when I said "Cerfing". ;-)
Jim
Post a reply to this message
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |
|
![](/i/fill.gif) |
| ![](/i/fill.gif) |
|
![](/i/fill.gif) |