Questions tagged [ibm360]
Questions regarding the IBM System/360 computers and their descendants.
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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 ...
- 15.3k
7
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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 ...
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2
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1
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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 ...
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3
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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 ...
- 2,438
20
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17
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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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5
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2
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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, ...
- 15.8k
2
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1
answer
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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 ...
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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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2
votes
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 ...
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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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3
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2
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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 ...
- 649
6
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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 ...
- 1,270
2
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0
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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
...
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