Questions tagged [ibm360]
Questions regarding the IBM System/360 computers and their descendants.
28 questions
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IBM 360 tool or utility to create custom IPL cards/tape/DASD?
If, on a System/360, I ran source code for a program intended to run on the "bare metal" through the assembler (probably Assembler D, F, or H on DOS/360 or OS/360), and then linked it, and ...
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What was the purpose of the System/360 unnormalized floating point add/subtract instructions?
Floating point was optional on System/360, but if it was present, it included separate addition and subtraction instructions that performed postnormalization of the result, or not.
Operands to all ...
- 841
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IBM System/360 channel interrupt priorities
IBM's System/360 Principles of Operation (A22-6821-7) says of channel interrupt priorities (page 112):
"The assignment of priority among requests for interruption from channels is based on the ...
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IBM documents giving System/360 device address assignment defaults/suggestions/recommendations?
Was there any IBM documentation giving specific device address defaults/suggestions/recommendations? It appears that all, or nearly all, device control units allowed selecting arbitrary device ...
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Books on IBM DOS/360
Were there any good books on IBM DOS/360 programming?
Or, for that matter, BPS, BOS,or TOS?
I know that many of the IBM manuals are on Bitsavers, but I'm looking for more introductory/tutorial level ...
- 841
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IBM DASD CKD records per track planning documentation
IBM's DASD (disk, drum) for the System/360 used a variable number of variable-sized Count-Key-Data (CKD) records on each track, rather than modern fixed-size sectors. The manuals for e.g. the 2311 and ...
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2
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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 ...
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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?
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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 ...
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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.
- 150
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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 ''...
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