Questions tagged [ibm360]

Questions regarding the IBM System/360 computers and their descendants.

Filter by
Sorted by
Tagged with
3 votes
2 answers

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 ...
No Name QA's user avatar
13 votes
5 answers

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 /...
No Name QA's user avatar
8 votes
1 answer

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 ...
davidbak's user avatar
  • 5,877
5 votes
3 answers

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 ...
No Name QA's user avatar
2 votes
0 answers

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 ...
Raffzahn's user avatar
  • 208k
1 vote
3 answers

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 ...
No Name QA's user avatar