IBM 360 Halve Instructions
Talking about the Halve instructions, they were an oddity as
To be sure, they halved an FPN, but did not normalize afterwards.
Hence, an extra bit could be lost at the least-significant end.
To avoid further loss of least-significant bits in subsequent add/
it was necessary to normalize, presumably by adding zero.
The main advantage of the halve instructions was that they were
much faster than
using a divide instruction.
Robin Vowels <email@example.com> wrote:
> Talking about the Halve instructions, they were an oddity as
> originally implemented.
> To be sure, they halved an FPN, but did not normalize afterwards.
> Hence, an extra bit could be lost at the least-significant end.
> To avoid further loss of least-significant bits in subsequent add/
> subtract operations, it was necessary to normalize, presumably
> by adding zero.
> The main advantage of the halve instructions was that they were
> much faster than using a divide instruction.
Even so, HALVE has to be used carefully.
Multiplying by two and then HALVE can lose low bits, such that
the last iteration of square root is done differently on non
base two machines. (And presumably those writing cube root
on non-trinary machines should also be careful.)
...Auction: IBM touch screen system /Complete system all IBM
Ends Feb-17-06 15:11:28 PST
What is that wire going into the keyboard between CTRL and =E2=86=90 ?
Touch screens are neat. I used them when I worked on the PLATO
Computer Aided Instruction system for the University of Illinois,
Chicago Medical Center.
I wonder what ever became of Plato?
Dan-the K wrote:
> What is that wire going into the keyboard between CTRL and =E2=86=90 ?
Dan, I enlarged the system photo to 400%, and all I can see between the
right Ctrl key and the left arrow key is the normal plastic keyboard
case -- no wire (maybe my eyes are getting too old). Now, at the
bottom of the keyboard between the right arrow key and the keypad 0 is
the system end of the keyboard cable -- but that's just resting against
the bottom edge of the keyboard case.
> Touch screens are neat. I used them when I worked on the PLATO
> Computer Aided Instruction system for the University of Illinois,
> Chicago Medical Center.
It's a small world -- I once owned the rx/uia/cerl account (for the
non-PLATO folks, uia meant "University of Illinois Author", and CERL
was the Computer-based Education Research Laboratory).
And if I said, "Bring on the Soul Snarf!", would you know what I was
> I w...IBM System /360 nostalgia
On Friday, 20 July 2012 04:03:43 UTC+10, John Levine wrote:
> On a 360/30, the MVC to move a 100 character field took 330us, or 355
> if it used EX to set the field length. Do a 20 of those for a 2K disk
> block and it's 6ms just to move the data, an appreciable fraction of
> the time to do the disk I/O. These days, moving that much data is
> probably under 50us, so who cares?
The model 30 was a small entry-level machine, and wasn't particularly fast.
Comparable figure for a first-generation machine (1955)
to move 100 characters took 512uS.
Model 40/44 ...IBM 360/370 instruction set architecture
Does anyone know any links for the IBM 360/370 instruction se
I've been looking for it for a very looooong time but i've found n
good site about it. I just need a list of instructions for 360/370
addressing modes and instruction formats. Please help m
On Thu, 09 Jun 2005 11:16:40 -0500,
firstname.lastname@example.org (Adam_L) wrote:
>Does anyone know any links for the IBM 360/370 instruction set
>I've been looking for it for a very looooong time but i've found no
>good site about it. I just need a list of inst...IBM System 360 conditional branch after unsigned arithmetic
I am trying to understand the IBM S360 condition codes. IBM took a
fascinating approach, so different from the NZCV arrangement that I am
familiar with, and set just two bits to indicate the condition.
After some working through of examples the IBM idea seems easy enough where
after a signed add, for example the instruction sets the two-bit condition
code to one of the following values.
0 meaning sum was zero (mask 1000)
1 meaning sum was < zero (mask 0100)
2 meaning sum was > zero (mask 0010)
3 meaning an overflow occurred (mask 0001)
The branch instruction inclu...IBM System/360 40 Years Old Today
It was 40 years ago today (4/7/64) that IBM announced its System/360
line of mainframe computers, introducing an architecture still used
today and breaking new ground.
S/360 was built with the idea of teleprocessing and soon it was used
for considerable data communication. The Bell System's had a lot of
business from this, both dial-up and private lines. I don't think
S/360's precedessors, such as the 7090, did much teleprocessing except
in very specialized circumstances. The S/360 architecture of channels
and interupts worked well with teleprocessing requirements. The
growth of S/360 fueled Bell System work in modems and data
Today we take all the following for granted, but it was a major
technological and software achievement for IBM to achieve the
following features in 1964.
The success of S/360 and its successors in the marketplace made
computers a commonplace item in industry and government. The
principles of its architecture and operating system, described below,
were included in the PC.
S/360 had several advantages:
1) A uniform machine for both science and business applications.
Science/engineering requires high speed numeric processing, typically
using fixed binary words. Business requires character manipulation,
typically using single alpha-numeric characters grouped in varying
lengths. Companies could now use a single machine to do both kinds of
2) A uniform machine for both lar...Re: IBM System/360 40 Years Old Today
My first computer systems were IBM 7040, 7044, 7090, 7094 and 1401.
After about a year, I encountered my first IBM System 360 machines and
since then have have worked with most of the S/360 line (models 22,
30, 40, 44, 50, 62, 65, 67, 75, 85 and 91) and many of the S/370 and
S/390 lines which are follow-on architectures. I have worked also on
the RCA Spectra 70/45 with similar architecture and on many of the
Amdahl machines from the V6 to the 5890 models which were capable of
running the IBM S/360, S/370 and S/390 operating systems.
In article <email@example.com>, Jeff nor Lisa
> It was 40 years ago today (4/7/64) that IBM announced its System/360
> line of mainframe computers, introducing an architecture still used
> today and breaking new ground.
> S/360 was built with the idea of teleprocessing and soon it was used
> for considerable data communication. The Bell System's had a lot of
> business from this, both dial-up and private lines. I don't think
> S/360's precedessors, such as the 7090, did much teleprocessing except
> in very specialized circumstances. The S/360 architecture of channels
> and interupts worked well with teleprocessing requirements. The
> growth of S/360 fueled Bell System work in modems and data
The IBM S/360 architecture is not well suited to
character mode teleprocessing as the CPU cost for
...Re: IBM System/360 40 Years Old Today #2
firstname.lastname@example.org (Randolph J. Herber) wrote
Thank you for the comprehensive comments.
> But, these machines  were slow:
> each character processed, even the characters in the
> instructions, required 11 microseconds of CPU time.
According to the Campbell-Kelly-Aspray (sp?) book, the biggest feature
of the 1401 was not the CPU but rather the fast and clean 1403
printer. I would guess that the 1401 CPU was hardware bound-- meaning
the slow printer and reader determined throughput, but the fast 1403
was a big improvement over what else was out there at the time. The
big machines used the 1401 as a spooler.
I know many programmers who have a warm feeling of the 1401.
> What made it such a success was this was the first
> architecture from IBM that was available with a very wide
> price and performance range were the vendor promised that if
> one wrote their programs to a certain not particularly
> difficult standard then the program would execute correctly
> across the entire range and where the architecture was
> reasonably good for I/O, numerical computation, data movement
> and character processing. It was one of the very first such
> architectures in the world.
I can't help but wonder if today's telephone systems, made from many
different manufacturers, share that upward compatibility. That is, if
a company wanted to upgrade from a small PBX to a bigger one, would
i...HELP: crazy from DLL invoking from PL1 on IBM Rational Developer for System z (Windows platform)
I am trying to invoke external dll from PL1 with IBM Rational
Developer for System z tools under the windows platform for several
days. unfortunately, I did not pass the compilation. Any help would be
>>>>>>>>method in the test.dll which written by C++>>>>>>>>
int test1(char* str1)
>>>>>>>>>>>>>>>>>test.dll>>>>>>>>>>>>>>>>>>>>>>&...Auction: IBM System/36 5362 System Unit System Reference Codes (wooden shoes, ho!)
Ends Dec-21-05 10:59:09 PST
IBM System/36 5362 System Unit System Reference Codes
End time: Wednesday, December 21, 2005, at 10:59:09 AM Pacific Standard
[The output above was from my program simply pasted into the newsreader
window. I am still ironing out some bugs like if there is embedded
quotes in the item description or if eBay truncates certain strings.
Once that is complete I will offer it to the masses]
...IBM Personal System/2
I have a box labeled: IBM Personal System/2 - System Library and there
are tons of little books inside containing detailed documentation
regarding PS/2 computer systems and OS/2 2.0. They are in incredibly
good shape. Covers still shiny as ever. Anyone know how much I could
make selling these?
CT the Pragmatic
"Tim Knight" <email@example.com> wrote in message
> CT the Pragmatic
Aw, I dunno.......... if you find the right *victim*, they could be worth
dozens of dollars !
bobwatts, the persistent realist
To return email, remove anti spam measures
Watts Carburetion Service
IT Director Johnson Automotive Inc.
Hi Bob (The Persistent Realist).....
I just meant I didn't know how much it would be worth.......
I always felt that Business 101 dictated that if both the buyer and the seller
walked away with smiles, it was a good deal......regardless of the size of the
Just this morning I sold a 1985 Chrysler K-car 4-banger with a mean sonofabitch
of a ...why so difficult to get IBM BP quote on IBM i systems?
I am getting nowhere asking different business partners for quotes on
the following IBM i edition Power systems:
From each BP I am dealing with I ask for the quote and get back
something which is twice the price. Some provide detailed pricing,
others say IBM does not allow details to be quoted.
When I call IBM directly and ask questions like what is the difference
between versions of the BCS chassis, I am told I have to ask the BP.
Problem is t...Auction: IBM Video Capture Adapter / A for IBM Personal System/2
BIN 9.99 12 available $10 shipping
Reply to firstname.lastname@example.org
Can someone forward one to me in France please ? I don't want to do an
expensive wire transfer to get one.
...[auction US] IBM MICROCHANNEL 1200-2400BPS MODEM FOR IBM PS2 SYSTEMS
Beware! The seller doesn't seem to care much about which card you'll be
...Auction: IBM Video Capture Adapter / A for IBM Personal System/2 #2
Sealed in box, includes cables. 13 available.
...Auc-tion: IBM MICROCHANNEL 1200-2400BPS MODEM FOR IBM PS2 SYSTEMS
End time: Dec-21-06 00:32:30 PST (4 days 11 hours)
Ships to: Worldwide
Item location: BERTONE MOTORS, CINCINNATI, OHIO, United States
"picture may not be actual item exactly; but is of and will be a PS2
microchannel modem; picture may not be exact card, I have several to sell
and they are not the same, specs are within that stated"
...[News] Oracle Brings Identity Management to UNIX/Linux, IBM on System i and System p
Oracle announces new Oracle Identity Management Software
,----[ Quote ]
| Oracle Authentication Services for Operating Systems is software that
| centralizes user management and authentication across major Linux and Unix
COMMON Prepares for the Power Systems Evolution
,----[ Quote ]
| Although that community has been 100 percent devoted to one platform and now
| that platform is being merged into a single set of iron that also runs IBM's
| AIX Unix and Linux, Dufault says, it is not like this is the dawning of a new
| day. He also points out that Frank Soltis, the chief scientist for the System
| i platform and the man considered to be the father of the AS/400, has been
| saying for years that in his opinion that the System i and System p hardware
| would likely merge. "It's not like anyone was blind sided," Dufault says.
Related and recent:
Will a Little Openness Solve Your Web Identity Crisis?
,----[ Quote ]
| I'm sure you can see the potential pitfalls of this architecture- what if you
| fall into the clutches of an inept or criminal OpenID service provider? It is
| easy to change to a new provider, and to set up several different OpenIDs,
| but that doesn't solve all the problems caused by a shady or incompetent one.
| You could, in classic FOSS do-it-yours...IBM System/36 ISA board (turn your PC into a System/36) auction Netherland!
Ends Mar-11-05 11:28:49 PST
Now THIS is pretty damn odd.
Louis Ohland wrote:
> Ends Mar-11-05 11:28:49 PST
Look, we can search Ebay for ourselves if we want to. Stop spamming.
"The geek shall inherit the earth."
-- Rainer Wolfcastle in "Undercover Nerd"
Mario Berger schrieb:
> Louis Ohland wrote:
>> Ends Mar-11-05 11:28:49 PST
> Look, we can search Ebay for ourselves if we want to. Stop spamming.
When a honoured member of the MCA family posts an ebay auction number
for items related to the interest of the other group members, it is not
All Louis missed, is the note "not related".
I would have missed a ROTFL if George didn't post the XGA-2 for 225$
only auction ;-)
These opinions are mine. All found typos are yours.
Mario Berger wrote:
> Louis Ohland wrote:
>> Ends Mar-11-05 11:28:49 PST
> Look, we can search Ebay for ourselves if we want to. Stop spamming.
Mario, it would be a good idea to find out who the regu...SA22-7228 "IBM RISC System/6000 and System/390 Server-on-Board"
SA22-7228 "IBM RISC System/6000 and System/390 Server-on-Board". This
manual is for Micro Channel systems.
...Auc-tion: IBM mainframe emulation software, OS/360 DOS/360 VM/370
BIN : $12.00
Ships to: Worldwide
Item location: Jerusalem, Israel
Quantity: 25 available
cs2001 Hercules IBM System 360/370, ESA/390, z/Architecture Emulator, with
About the Hercules Emulator
The emulator is available for Windows and for Linux. The source is also
available, so adapting to any form of UNIX should be practical. This
emulator is a serious piece of work, but it does have some limitations that
make it not quite suitable for a production environment. However, it is
under development and you get the source. More information and downloads can
be had from http://www.conmicro.cx/hercules/ .
The CD also includes the following Operating Systems:
OS/360 version 21.8
DOS/360 version 26.2,
TOS/360 version 26.2
The programs are either public domain or some kind of public license. The
IBM software was simply never copyrighted because IBM conceived of no need
to do so. I believe this software to be useful, but I cannot give assurances
about the suitability of any package for a particular purpose.
In addition, there are links to other useful resources.
Shipping is $3.00 Worldwide
DOS/360 ?!? Sounds like mainframe for home use...
...Auction: Vintage IBM 5362 System 36 Computer System S/36 (LA local pickup only)
Santa Cruz, California
On Nov 29, 8:52=A0pm, Louis Ohland <ohl...@charter.net> wrote:
> BIN http://search.ebay.com/200344827100
"Here's your chance to have a small IBM system that's constructed like
their mainframes of years gone by."
That's either literary license, or the seller has no concept of
classic mainframe construction. The 5362 is built in a manner similar
to the RT/PC or the RS/6000 7013s, even the high-end 5360 was not up
to mainframe construction standards.
> On Nov 29, 8:52 pm, Louis Ohland <ohl...@charter.net> wrote:
>> BIN http://search.ebay.com/200344827100
> "Here's your chance to have a small IBM system that's constructed like
> their mainframes of years gone by."
> That's either literary license, or the seller has no concept of
> classic mainframe construction. The 5362 is built in a manner similar
> to the RT/PC or the RS/6000 7013s, even the high-end 5360 was not up
> to mainframe construction standards.
> Rick Ekblaw
It's successor: the white AS/400 had expansion cards that did look a bit
like the mainframe stuff. My advise would be to look for a more recent
AS/400 if you like the concept of an all in one sturdy box.
One thing to say about the AS/400 is that it's I/O was generally better
designed than the contemporary PCs and server...A Walk Through The Xbox 360 Evaluation Lab [3DO, WebTV, IBM, ATI joined up to make Xbox 360]
Tuesday, August 16, 2005
A Walk Through The Xbox 360 Evaluation Lab At Microsoft's Mountain View,
Dean Takahashi, 12:01 AM in Dean Takahashi, Gaming
(This story is a companion to a shorter piece we're putting in the
Leslie Leland was kind enough to walk me through the product evaluation and
reliability labs for the Xbox 360 at Microsoft's Mountain View, Calif.,
campus earlier this month. She's one of the hardware engineers who makes
sure that the box will work when i...IBM System z9
Just try to guess which OS will *not* be running on it
Longhorn error#4711: TCPA / NGSCP VIOLATION: Microsoft optical mouse
detected penguin patterns on mousepad. Partition scan in progress
to remove offending incompatible products. Reactivate your MS software
In comp.os.linux.advocacy, Peter K�hlmann
on Tue, 26 Jul 2005 22:53:55 +0200
> Just try to guess which OS will *not* be ru...IBM System 34
My cousin asked me if I knew anyone that would fix or have parts for this
Any one know someone who has parts or will work on an IBM System 34. It is
located in Clifton Heights SW edge of Philly. Sounds like it needs a power