Questions tagged [ibm360]
Questions regarding the IBM System/360 computers and their descendants.
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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 ...
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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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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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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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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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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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