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,...
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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 ...
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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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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 ...
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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?
9
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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 ...
3
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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 ...
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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 ''...
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 ...
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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 ...
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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 ...
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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, ...