Questions tagged [ibm360]
Questions regarding the IBM System/360 computers and their descendants.
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What is the full name of IBM CP-67/CMS' DUMPD command?
I am reading the User Guide of CP-67. Under the command DUMPD (page 373), it describes its Purpose as:
The DUMPD command prints the contents of one direct-access record,
specified by a CCHHRR address,...
12
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4
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Does anyone have any information on GUTS (Gothenburg University Timesharing System)?
Gothenburg Universities Computer Centre (in Sweden) developed a timesharing system for IBM mainframes, known as GUTS (variously expanded either as ''Gothenburg University Timesharing System'', or as ''...
17
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Was bootloading from punch cards possible on System/370 machines?
I have been idly looking into how System 370 works, though mostly at software and VM/370 OS. As a part of the system generation process, one needs to use DMKDDR utility and others. So I was curious ...
9
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1
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How did the OS/360 link editor achieve overlay structuring at linkage time without annotations in the source code?
The OS/360 link editor was, according to Brooks (OS/360 project manager): "one of the finest overlay facilities ever built." "It allows overlay structuring to be done externally, at ...
5
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0
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Did the Soviets need industrial espionage to get IBM software pre-1970?
Due to lack of the OS-level file system on the BESM-6, and to deficiencies of data visualization tools which could help people decide which blocks of a system disk could be reused (the line of ...
10
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1
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Did the IBM 1401 have much better code density than the 360?
Reading an old thread https://groups.google.com/g/alt.folklore.computers/c/53C2adEQ5jE I see a surprising claim:
I told an IBM salesman once that IBM had so bollixed up the architecture
that our ...
8
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How did the IBM 360 detect memory errors?
What logic did the IBM 360 use to detect, and perhaps correct, memory bit errors?
3
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2
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How can the current date be accessed from DOS/VS assembler?
In assembler on an old /370-125 running DOS/VS I can access the TOD (Time of day) with GETIME, i.e. the time since midnight. But I want to be able to print the date.
11
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The MAC-360 programming language developed in the mid 1960s
On SE Space Exploration, one of the answers to this question, Fortran and the Apollo 11 mission states that the MAC-360 language, developed around 1967 by Hal Laning, was used to do develop ...
5
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2
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Any informations on IBM's "Generalized Information System" still available?
I wonder if anyone has documentation left on this topic. In the early 80's, I used to be a 3270 terminal operator, and I wrote programs with GIS. I remember that this language was rather mighty but ...
9
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Weird example code for CALL/360:BASIC
The CALL/360:BASIC manual has a couple of simple examples of file I/O. This one has me scratching my head:
10 OPEN 10, 'ITEMFILE', INPUT
20 GET 10: A$,A,B,C,D
30 LET Al = (A+B+C+D)/4
40 PRINT USING ...
9
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1
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Why did IBM skip "System/380" as a mainframe family name?
I've been reading Exhibit 14971 from US vs. IBM (Parts 1, 2, 3) which seems to give a very good overview of the history of the computer industry up to 1980, particularly the way IBM handled its ...
8
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4
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How was the APL character set represented on IBM mainframes?
The APL language used a unique set of characters, and additionally allowed overstriking of some characters on the terminal to form characters that were used in the language. When an APL workspace was ...
2
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1
answer
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Did the IBM 7030 "Stretch" influence the design of PL/I?
The IBM 7030's fixed-point arithmetic model was unusual: binary numbers could have any number of bits from 1-64. Similarly, PL/I's FIXED BINARY data type has a variable number of bits. On the other ...
21
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What was the rationale behind 32-bit computer architectures?
Though today various power-of-2 word sizes seems to be the norm, back in the 50-60s multiple-of-6 word sizes was more popular and was required by Department of Defense(DOD) in particular.
36-bit ...
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Were any IBM mainframes ever run multiuser?
Now of course there is a sense in which they were – some mainframe installations supported thousands of users! But there is a distinction.
Consider the familiar fixture in so many 80s computer science ...
5
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Were there "higher level programming" macro packages for the IBM Macro Assembler?
The IBM/360 Macro Assembly language was quite powerful, allowing non-trivial compile-time string manipulation.
Did macro packages exist which would facilitate programming at a (slightly) higher level, ...
13
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When did IBM start to use ASCII?
I’m trying to figure out when IBM switched to ASCII and when ASCII became a worldwide standard.
Moreover, did IBM make ASCII standard worldwide?
What I have found:
According to Wikipedia, IBM System /...
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3
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Why did IBM System 360 have byte addressable RAM
According to wiki IBM System 360 had byte addressable RAM.
Previously IBM had machine with word addressable memory.
Did they make a switch for comparability between different machines?
Or it was just ...
5
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3
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Why did IBM System /360 have byte addressable RAM, but didn't have 8 bits registers
According to wiki IBM System /360 had only 32 and 64-bits registers for data.
I'm wondering if they used 8-bits symbol it means that they stored it in a 32-bits register.
Did they have any performance ...
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Why did IBM 7030 or IBM 360 use byte and word addressing simultaneously
In 1950s machines had a 36 bit words. And in this word we could pack symbols using 6 bits. And to fetch this symbols from the word programmer should do it using bit manipulations.
In 1961 IBM released ...
2
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When and with which system or software was IBM's system of tape headers (VOLx, HDRx, ...) introduced?
Background:
IBM compatible tape structure (*1) consists of a series of label blocks describing the volume and each file (Data Set). Essential the structure looks like this:
VOL1..9 Volume header
...