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Re: Question on ProDOS SmartPort drive remapping



vladitx wrote:
On Dec 6, 3:57 pm, "Peter Watson" <paw77@N_O_hotmail_S_P_A_M.com>
wrote:


The name pretty much described the program. It consisted of one line of
assembler which generated two bytes of executable code:
   BR  R14
This basically meant "return to caller", since by convention the return
address on entry is stored in register 14.


Being too young for the IBM mainframe times and missing the knowledge
of it, once by looking at a short assembly excerpt I suspected that
ARM's architecture borrowed ideas.

Essentially everything after the 360 borrowed ideas from the 360.
It was unavoidable for an architecture that introduced so many
now standard ideas, like byte addressibility, alignment, general
registers, long base registers with short instruction displacements,
etc.

I realise that System/360 didn't *originate* all of these concepts,
but it *universalized* them, and drew them together in a coherent
architecture.

-michael

NadaPong: Network game demo for Apple II computers!
Home page:  http://members.aol.com/MJMahon/

"The wastebasket is our most important design
tool--and it's seriously underused."