Hi everybody.
This is something a computer geezer like me should know. But I don't.
I've read some things that seem to imply that *some* of the oldest
drive/formatters did NOT write a longitudinal parity frame at the end of a
block. (They did have horizontal parity, of course.)
If it's true then a drive reading such tapes would not have an easy way of
telling whether frames had been dropped during a read. Does this ring true
to anybody out there? Any observations welcome.
best regards,
Chris Muller
Muller Media Conversions
32 Broadway, suite 1214
New York, NY 10004
http://www.mullermedia.com
212-344-0474 or 800-OLD2NEW
The comment I made was based on another person's view that p-code was intrepreted and so was .NET - apples and apples sort of thing... I don't recall any Microsoft product that created p-code which could be executed without compiling and then you could compile the p-code and execute that too.
-----Original Message-----
From: Jim Battle <frustum(a)pacbell.net>
Sent: Sep 29, 2004 8:46 AM
To: General Discussion@null,
On-Topic and Off-Topic Posts <cctalk(a)classiccmp.org>, null@null
Subject: Re: Code Generation .NET
Steve Thatcher wrote:
> p-code never compiled down to native calls... .NET does
That sounded like an assertion waiting to be disproven. 15 seconds with
google produced this link:
http://www.threedee.com/jcm/psystem/
Heath Z-80 UCSD p-System, six 5 1/4" disks: "SYSTEM 1," "SYSTEM 2,"
"ZINT," "PASCAL," "UTILS," "Native code generator NZ84BP".
That was contemporaneous. Something more recent:
http://www.pascal-central.com/pcode.html
Spend a few more minute and find more links.
On Sep 29 2004, 8:23, John Foust wrote:
> At 02:02 AM 9/29/2004, you wrote:
> >I've hardly ever seen a commercial standard Cat3 / Cat4 / Cat5
/Cat5e
> >cable that was miswired with split pairs. Telephone cables wired to
> >the old USOC standard are different[1], but not usually fitted with
> >RJ45 plugs, and flat cables are obviously not twisted pairs.
>
> I agree, and I suspect any straight-through RJ-45 cable
> was for a telephone system, not networking. Perhaps
> Sellam knows examples.
ISDN S-bus sometimes uses flat cables for the last piece of flex
between wall and device (you shouldn't, because 1+2 and 7+8 are
sometimes used for phantom power, but many devices only use Tx and Rx
which are 4+5 and 3+6).
--
Pete Peter Turnbull
Network Manager
University of York
On Sep 29 2004, 9:48, Roger Merchberger wrote:
> Rumor has it that Pete Turnbull may have mentioned these words:
> >On Sep 28 2004, 15:52, Steve Thatcher wrote:
> >Do you expect to pick up a book on some
> >strange programming language or some new science and understand the
> >syntax without some explanation?
>
> If you do, this is the language for you:
>
> http://www.catb.org/~esr/intercal/
It's actually quite a popular and well-known language amongst the
systems programmers at York!
--
Pete Peter Turnbull
Network Manager
University of York
I recently acquired a DW08-B backplane. I am interested in reconditioning
it, but I can't find drawings for it online. (I found the drawings for the
DW08-A, thanks.) Does anyone have drawings for this lying around? (In a
pinch, even a module locator chart would help, because then I could trace
the wiring :-).)
Thanks,
Vince
>From: "Patrick/VCM SysOp" <patrick(a)vintagecomputermarketplace.com>
>
>> Why didn't they use * or X for AND then?
>
>The period is a convenient substitution for a dot that was used in math to
>indicate multiplication (the "real" symbol is usually represented as more
>vertically centered within the character cell). I have some books that also
>use "x", but that character is again a more (or sometimes less) stylized
>glyph than the simple upper- or lowercase "X".
>
>By the way, that plus (or) symbol in those same books is often a plus inside
>a circle. So I suspect the use of plain-old-plus is again a convenient
>substitution into ASCII.
>
>Patrick
Hi
Most times, a plus in a circle is to indicate an exclusive-or.
Dwight
actually, .NET is a platform where individual compilers (C#, J#, VB, Fortran, etc) generate an abstract code that is compiled and run in the .NET runtime. C# can not run and execute Cobol for example, but you can freely intermix classes that each could be written in any language. Any class no matter what language it is written in can be called by a class or call another class.
A class may not be compiled until runtime (JIT - just in time), but once it is compiled then it is available immediately.
best regards, Steve Thatcher
-----Original Message-----
From: Jules Richardson <julesrichardsonuk(a)yahoo.co.uk>
Hazy memory, but I thought .net was typically C# in a distributed
environment - in other words, Microsoft's rip-off of Java and JINI with
the added "benefit" of vendor lock-in :-)
I thought C# was *usually* interpreted, just with the option of
compilation if needs be (just as Java bytecode can be compiled to native
code if desired). Fair call on the compiler included with the OS though.
> Also the code generator is capable of supporting different .Net languages.
> This means that a C# program can write and excute Cobol code, or a Visual
> Basic program could write Fortran code and execute it.
Now that is interesting. A developer's nightmare, but interesting :-)
seeya,
Jules
On Sep 28 2004, 15:52, Steve Thatcher wrote:
> from a self documenting sense, it makes no sense...
>
> when someone can pick up a logic description and understand it
WITHOUT having to figure out what each sytmbol means in the context of
the usage, then it is simply more understandable. If I picked up
something that had two binary numbers wiht a PLUS sign inbetween, I
would not assume that it meant OR, only if you would dig further does
the PLUS sign make sense. If you simply said OR, then there is no
confusion and it is self documenting. I think Sellam was trying to make
this point with regards to symbology.
>
> I agree with Sellam about the insanity part... The symbols are
> arbitrary and WORK as long as you have your language description at
> hand.
I don't -- agreed the symbols are to *some* extent arbitrary, but I
agree with Dwight. If they're arbitrary, then +/. are just as good as
|/&. The symbols Dwight used are part of *the* standard for logic
expression in Boolean mathematics, and make good sense if you think
about it (or know a little about it). The overloading of multiple
context-sensitive meanings for things is common in mathematics,
programming, and lots of other places. You just have to learn to live
with it. If you learn a new discipline or language, you have to learn
the semantics (just as a physicist knows that stress and strain are two
different things while the man in the street, having read his OED,
"knows" they're the same). Do you expect to pick up a book on some
strange programming language or some new science and understand the
syntax without some explanation?
As for confusing addition and the logical OR function with binary
numbers, you don't normally perform logic on binary numbers, only on
bits representing truth values. Describing "1011 OR 0101" as part of a
logic equation is sloppy; it's actually four put together.
And lastly, AND and OR are just two binary logic functions. There are
fourteen more, if remember my first year maths, all with ASCII symbols,
all of which predate C.
I sympathise with those who've not seen it before. It can be hard to
understand at first; logic is not common sense. It is, however,
logical :-)
--
Pete Peter Turnbull
Network Manager
University of York
Rumor has it that David V. Corbin may have mentioned these words:
> >>> >>>
> >>> Can you create self modifying code in any high level
> >>> language, the kind of code where the application program
> >>> actually changes it's own instructions?
> >>>
> >>> I know in C it is possible to pass an address of a function
> >>> to a function, that's not really what I mean.
> >>>
>
>Actually this is (sort of) becoming more common. One exciting feature of a
>new platform by the software vendor who shall not be named,
Why not? Some of us aren't "in the trenches" so to speak WRT newer software
& languages.... I would be interested to know which platform that actually was!
> is that the compiler is actually part of the runtime.
So, in other words... it's an interpreter. Novel idea, that! ;-P
> This means that any program can
>write source code to a string (or other structure) and compile and execute
>it!!!!!!
Lots of languages have eval() nowadays... most people think the use of it
is as evil as self-modifying code.
Dunno, if you ask me -- it sounds like "yet another gaping security hole
waiting to happen" to me...
Laterz,
Roger "Merch" Merchberger
--
Roger "Merch" Merchberger --- sysadmin, Iceberg Computers
Recycling is good, right??? Randomization is better!!!
If at first you don't succeed, nuclear warhead
disarmament should *not* be your first career choice.
At 05:07 PM 9/28/2004, David V. Corbin wrote:
>To the best of my knowledge, the Microsoft .NET platform is the first
>run-time environment [not development environment] in which a compiler,
>linker and all of the associated capabilities are included. If you have a
>windows machine [XP, 2K] and have applied the windowsupdates, then all of
>these tools are already resident on your machines!
I guess that would explain why it's a 20 or 30 meg download,
once you've got the main system and the 11 meg patches.
And they're pushing it out as fast as they can - it's part
of WinXP SP2, no?
- John
