Access to a ridiculous computer? :-D

Has anyone here got access to a ridiculous computer? Something like:

CHAR_BIT == 9
PADDING_BITS(int) != 0
NUMBER_SYSTEM == SIGN_MAGNITUDE
Null pointer bit pattern == All ones

I'm writing some fully-portable code and would love to actually compile it
for, and test it on, a very strange machine :-D

Or does anyone know of a particular machine I could get my hands on very
cheaply just for playing around with, something very strange which I can
get a compliant C89 compiler for? An old supercomputer perhaps? The main
thing I'd want is a strange value for CHAR_BIT, but I'd be ecstatic if the
integer types had padding aswell!

--
Tomás Ó hÉilidhe

"Tomás Ó hÉilidhe" <toe@lavabit.comwrites:Your best bet for CHAR_BIT 8 is probably a DSP (Digital Signal
Processor), but I think those systems tend not to have hosted C
implementations (i.e., much of the standard library may be missing).

You *might* be able to obtain an old working supercomputer for not too
much money, but the power and air conditioning costs are likely to be
huge. In any case, on the relatively old supercomputers I've used
(Cray T90), CHAR_BIT==8 (the compiler went to considerable effort to
make this work, even though the hardware didn't support 8-bit memory
access. But I believe at least some of the predefined integer types
did have padding bits.

cray-cyber.org offers free access to some old supercomputers; some of
them are available 24/7, others are not.

--
Keith Thompson (The_Other_Keith) <kst-u@mib.org>
[...]
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"

In article <Xns9A18EBF80CB1Etoelavabitcom@194.125.133.14>,
Tomás Ó hÉilidhe <toe@lavabit.comwrote:
Possibly you could use one of the emulators at simh.trailing-edge.com.

"SIMH implements simulators for:

* Data General Nova, Eclipse
* Digital Equipment Corporation PDP-1, PDP-4, PDP-7, PDP-8, PDP-9, PDP-10, PDP-11, PDP-15, VAX
* GRI Corporation GRI-909
* IBM 1401, 1620, 1130, 7090/7094, System 3
* Interdata (Perkin-Elmer) 16b and 32b systems
* Hewlett-Packard 2114, 2115, 2116, 2100, 21MX
* Honeywell H316/H516
* MITS Altair 8800, with both 8080 and Z80
* Royal-Mcbee LGP-30, LGP-21
* Scientific Data Systems SDS 940"
--
"There are some ideas so wrong that only a very intelligent person
could believe in them." -- George Orwell

"Tomï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï ¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ " wrote:Such a machine would be interesting for testing portability. The best
solution is a configurable simulator and compiler that lets you specify
many of these implementation-defined and otherwise variable attributes.

Writing the simulator sounds interesting -- writing a configurable compiler
seems like a lot of work!

Perhaps something based on a C language interpreter would be better. Are
there any C interpreters that would make a good starting point for a
configurable target?

--
Thad

On Tue, 1 Jan 2008 17:11:48 -0600, Tomás Ó hÉilidhe wrote
(in article <Xns9A18EBF80CB1Etoelavabitcom@194.125.133.14>):

There was a DS9K for sale on ebay last week, but somebody snapped it
up.

--
Randy Howard (2reply remove FOOBAR)
"The power of accurate observation is called cynicism by those
who have not got it." - George Bernard Shaw

Randy Howard wrote:... and left the seller negative feedback, in ones' complement.

More seriously: The IBM AS/400 (iSeries?) is said to handle
pointers in a way that trashes some widely-held but non-portable
assumptions. It doesn't meet all your requirements for strange-
sized characters and so on, but it might be worth while seeing
whether IBM operates a public grid or something on which they'll
rent you some time. (If your stated goal is an AS/400 port of
the software, they might even waive a chunk of the rental.)

--
Eric Sosman
esosman@ieee-dot-org.invalid

I came across Univac machines today. Supposedly one of them had 72-Bit
bytes.

I also read that one of their machines consumed 125 kW :-O I plugged
two 2 kilowatt heaters into an extension lead today, and the *extension
lead* got nice and hot, never mind the heaters.

--
Tomás Ó hÉilidhe

"Tomï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï ¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ " wrote:<offtopic>
Don't Do That. At least in the UK, 4kW through one plug is over 17A of
current (230V voltage), and you shouldn't ever try to draw more than 13A
through a plug. Many house fires have been started in this way.

In other countries, it's still a bad idea, though the details may differ.
</offtopic>

PS: FYI, your name is still screwed in my newsreader.

On Fri, 4 Jan 2008 05:04:18 -0600, Philip Potter wrote
(in article <fll3rj$kh9$1@aioe.org>):
Get a better one.

--
Randy Howard (2reply remove FOOBAR)
"The power of accurate observation is called cynicism by those
who have not got it." - George Bernard Shaw

Philip Potter <pgp@doc.ic.ac.ukwrote in comp.lang.c:
(I find the ambiguous spelling of "lead" irritating so I'm going to
replace it with "led" or "leed" where applicable)

The extension leed has four sockets, each of which leed to a common 13 A
fuse.

I should be able to plug whatever I want in wherever I want... worst case
scenario being a blown fuse.

(I originally set out writing this post to prove you wrong... but I did
the calculations and you turned out to be right)

Power = Voltage * Current
4000 = 230 * Current

Current = 4000 / 230 = 17.4 A

My original argument would have been that I should be able to plug
anything in wherever I want because the plugs all have 13 A fuses, but
now I'm at a loss to explain why a fuse wasn't blown when I was drawing
17.4 amps through one plug... ?

There's only two reasonable conclusions I can draw. Either:

A) The fuse is letting 17 A pass, and so isn't really a 13 A fuse at all.
B) Each heater is in fact only 1.5 kW (or maybe just one of them is
weaker)

Anyway, a question I'd like to ask: Should an actual plug or leed
ever become hot? Because the plastic of the plug from the extension leed
going into the wall was pretty hot, as was the leed.

I'm an electronic engineer myself but I still wouldn't have batted an
eyelid about plugging things in willy-nilly, (even into a mutli-adapter),
because the worst thing that should happen is a blown fuse.

I bought a smoke alarm along with the heaters though, just in case,
and I have it mounted right above them. I've got smoke alarms on the
ceilings of the rooms in my house, but I've also got ones mounted
specifically above high-risk devices (my washing machine, dryer, and the
heaters). I've only ever had one fire in my house and it was in a washing
machine; thankfully it was noticed in time and the unit was dragged out
into the back garden before any real damage was done.

--
Tomás Ó hÉilidhe

Randy Howard wrote:
A better what? Newsreader? Tomas (or his Newsreader) is violating
NNTP message standard, by using non verbatim 7-bit ASCII
characters in the name field. There is of course a way to put
extended characters in there, by using a specially encoded
format. However some Newsreaders need to have this enabled
explicitly, and some can't encode in that way.

Tomas uses Xnews, which can decode encoded NNTP headers, but
can't encode. So he has to provide the encoded field himself or
use a different Newsreader or don't use extended characters in
Header fields.

Wolfgang Draxinger
--
E-Mail address works, Jabber: hexarith@jabber.org, ICQ: 134682867

"Tomï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï ¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ï¿½ " wrote:[snip]
I am not an expert by any means, but I was told at school many, many
times never to overload a socket. The only conclusion I can come to is
that although the fuse *should* protect the plug and cable, if that fuse
doesn't work as it should then you've got a problem. Fuses are blunt
devices - they don't trigger immediately and they don't trigger at
exactly 13A. And, too often, the wrong fuse gets fitted to a plug.
Making a fuse a single point of failure is probably not a good plan.

I would take a hot cable as being a significant warning sign. If the
cable was hot, I'd say it was carrying more current than it should.

But again, I'm not an electrician.
Ouch!

Philip Potter wrote:
(replying to tom who wrote)The epitaph of many a dead householder.
Correct. But offtopic.
Also correct, and also offtopic.

--
Mark McIntyre

CLC FAQ <http://c-faq.com/>
CLC readme: <http://www.ungerhu.com/jxh/clc.welcome.txt>

On Sun, 06 Jan 2008 14:23:49 +0000, Philip Potter <pgp@doc.ic.ac.uk>
wrote:
The fuse is intended to protect the house wiring, and is sized
accordingly. It won't stop an overloaded extension cord from
overheating itself and whatever it comes in contact with.

--
Al Balmer
Sun City, AZ

Al Balmer <albalmer@att.netwrote in comp.lang.c:

If the fuse was intended to protect the house wiring rather than the
appliance's wiring, then it would make more sense to have fuses in our
sockets rather than in our plugs.

The max rating for the sockets is 13 A, and it's also 13 A for the plugs.

If the extension lead overheats when less than 13 A goes through it, then
it should be rated as maybe an 8 A extension lead, and accordingly have
an 8 A fuse in its plug.

Anyway I've come to conclusion that either:
a) The heaters are 1.5 kW instead of 2 kW.
or
b) The fuse is allowing 13 A to pass.

I'll look into it.

--
Tomás Ó hÉilidhe

On 6 Jan 2008 at 17:30, Al Balmer wrote:You know, it's the mindblowing, breathtaking, pisstaking hypocrisy of
this group that's the real killer.

If someone outside The Clique posts something heretical - perhaps they
assume their C implementation uses a call stack - then it isn't long
before HeathField's attack dogs (usually the insufferable Falconer or
the tragic Default Luser, sometimes Psycho Mackintyre or Martin "send
the men in white coats to pick me up in an" Ambuhlance, sometimes others
too) respond with a barrage of "OT - not C - not portable - I hope your
mother dies in agony you worthless piece of crud" posts.

But here we have a huge subthread, started, developed and kept going by
The Clique. Let's examine its subject. Oh, amateur electrics. (flicks
through the precious C Standard) Nope, current, wiring, plugs, cables,
none of them are their in N7342, or in N334124, or indeed in N2342141.
So where are all the messages saying "Cabling is an implementation
detail - take the discussion to a group for your platform"?

The amazing thing is that I think The Clique really are completely
unself-conscious about this - they just don't realize there's any
hypocrisy in what they're doing.

Antoninus Twink wrote:
Of course they do not see anything wrong.

Talking about wiring is allowed TO THEM. If I speak about
something like generic functions in C, or any "heresy" like
that, OFF TOPIC is immediately sent to me...

They started a thread about English poetry that lasted for a week.
(Around October or September last year). When I protested
they made a point in going ON and ON.

--
jacob navia
jacob at jacob point remcomp point fr
logiciels/informatique
http://www.cs.virginia.edu/~lcc-win32

Mark McIntyre <markmcintyre@spamcop.netwrites:
[...][...]Indeed. This whole thread, even though it's marked "[OT]", has
absolutely nothing to do with C, and is not appropriate in this
newsgroup. Please take it somewhere else.

--
Keith Thompson (The_Other_Keith) kst-u@mib.org <http://www.ghoti.net/~kst>
[...]
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"

Mark McIntyre <markmcintyre@spamcop.netwrites:
[...][...]Indeed. This whole thread has absolutely nothing to do with C, and
even though it's marked "[OT]", it's not appropriate in this
newsgroup. Please take it somewhere else.

--
Keith Thompson (The_Other_Keith) <kst-u@mib.org>
[...]
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"

jacob navia wrote:Jacob, you're smarter than this.

This subthread was started by me and Tomas. None of the members of "The
Clique" listed above have had anything to do with this subthread except
Mark McIntyre, who complained that it was offtopic.

There is no evidence in this subthread to support your argument of
hypocrisy. (There is also very little evidence to support your argument
of a "Clique".)

Phil

Philip Potter wrote, On 07/01/08 13:17:

<snip>

Also some of the "clique" deliberately took the conversation to email on
the basis that it was off topic. Eventually I would have complained
about it continuing here, but I was beaten to it.
--
Flash Gordon

jacob navia wrote:.... snip ...--

+-------------------+ .:\:\:/:/:.
| PLEASE DO NOT F :.:\:\:/:/:.:
| FEED THE TROLLS | :=.' - - '.=:
| | '=(\ 9 9 /)='
| Thank you, | ( (_) )
| Management | /`-vvv-'\
+-------------------+ / \
| | @@@ / /|,,,,,|\ \
| | @@@ /_// /^\ \\_\
@x@@x@ | | |/ WW( ( ) )WW
\||||/ | | \| __\,,\ /,,/__
\||/ | | | jgs (______Y______)
/\/\/\/\/\/\/\/\//\/\\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
================================================== ============

fix (vb.): 1. to paper over, obscure, hide from public view; 2.
to work around, in a way that produces unintended consequences
that are worse than the original problem. Usage: "Windows ME
fixes many of the shortcomings of Windows 98 SE". - Hutchinson



--
Posted via a free Usenet account from http://www.teranews.com

Keith Thompson wrote:True. However do you realize that this, and many other of your
posts, are multi-posted. The postings are something like 1 second
apart (in this case).

--
Chuck F (cbfalconer at maineline dot net)
<http://cbfalconer.home.att.net>
Try the download section.



--
Posted via a free Usenet account from http://www.teranews.com

CBFalconer <cbfalconer@yahoo.comwrites:
[...]Since rr.com is under a UDP, I'm posting through aioe.org.
Occasionally I accidenally post something through rr.com; when I
realize my mistake (usually *just* after I post the message), I post
again through aioe.org. A lot of sites, including aioe.org, aren't
seeing posts from rr.com (unless something has changed recently).

I'll try (a) not to post through rr.com and (b) if I forget, to
mention the problem in the aioe.org post.

--
Keith Thompson (The_Other_Keith) <kst-u@mib.org>
[...]
"We must do something. This is something. Therefore, we must do this."
-- Antony Jay and Jonathan Lynn, "Yes Minister"

On 9 Jan, 08:29, "Reagan Revision" <inva...@invalid.netwrote:
where? even if it isn't "a lot better" it may be
interesting.


--
Nick Keighley

On Wed, 2 Jan 2008 00:33:44 +0000 (UTC), roberson@ibd.nrc-cnrc.gc.ca
(Walter Roberson) wrote:
<snip>

PDP-10 in particular has 36-bit word, and although the (then) hardware
(now emulation) supports _any_ size byte, the obvious choice for C to
be >= 8 and pack (i.e. divide) into words is 9-bit. The heyday of real
-10s occurred before C was standardized, and I don't think there was
ever a confoming C then; as of about 2 years ago there was talk on
alt.sys.pdp10 of work on a gcc port (i.e. backend), but I didn't keep
track of whether it was completed. Even if so, to use it and otherwise
to develop and test your software on an emulated (or real!) -10, you
would need to learn (at least one of) the -10's OS(es), which at best
will take a good bit of your time.

-11 and VAX were mainstream byte machines. (VAX was the first
identified=major locus of unwarranted assumption of homogeneity --
"Not all the world's a VAX".) -1/4, -7/9, and especially -8/15 were so
small they would probably not support a useful C implementation. A
maxed-out 8-bank -8 could just barely fit the single 32KO object
required for nominal conformance to C89, but probably wouldn't be able
to run any program that would today be considered nontrivial and
useful. And that's assuming a crosscompiler; using an indigenous
compiler on one of these machines would be like beating yourself with
hammers just for fun.

- formerly david.thompson1 || achar(64) || worldnet.att.net

David Thompson <dave.thompson2@verizon.netwrites:
There is a distribution of TOPS-20 which is available including an emulator
for Linux at http://panda.com/tops-20/ (it isn't simh which is unable to
run TOPS-20 AFAIK). In this distribution, there is a C compiler (KCC)
which is more or less C90.

The gcc port I'm aware is a little older. It is available at
http://pdp10.nocrew.org/ along with the sources of KCC.

Yours,

--
Jean-Marc