Questions tagged [s360]
For questions about the IBM System/360 mainframe computer, and related software and hardware. For questions about IBM hardware in general, use the tag "ibm".
8 questions
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Mainframe Hater's Handbook?
The famous The UNIX-HATERS Handbook claims this mailing list had been inspired by TWENEX-HATERS(1) and other *-LOVERS mailing lists, a long tradition of MIT.
Moreover, the quote below implies there ...
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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 ...
- 65.3k
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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 ...
- 669
26
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1
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Was the IBM S/360 Responsible for Popularizating the 'A'-to-'F' Notation in Hexadecimal Numbers?
In the early history of computing before the mid-1960s, there was no universal, de-facto standard for the written representation of a hexadecimal number, different computer systems used their own ...
- 3,334
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Data length module of 3.2^n confusion in IBM system/360 architecture
I'm currently reading about the IBM system/360 architecture and there's a part that has me very confused:
The decision on basic format (which affected character size, word size, instruction field, ...
- 405
12
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2
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Did any 360-compatible machine implement registers in core?
In the early days of transistors, when they cost on the order of a dollar each, it was possible to implement CPU registers with magnetic cores (the technology used for main memory at the time) instead ...
- 65.3k
14
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What is the purpose of the yellow wired panels on the IBM 360 Model 20?
I just finished reading a story about an IBM 360 Model 20 rescue, and some of the pictures caught my eye.
Specifically this one:
Searching online, led me to several more pictures, all with obviously ...
- 243
19
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What's the deal with System/360's "USASCII" mode?
The original System/360 architecture had a bit in the Program Status Word that would select an "USASCII" mode rather than the usual EBCDIC. Setting this bit changed how the BCD arithmetic operations ...
