Running 4 copies of an operating system at once

Dick explained to me that they were using an operating system from a company called Telesoft. Telesoft, headed by UCSD Pascal author Ken Bowles, was building an Ada compiler on top of its ROS (Renaissance Operating System) product. He told me (and I remember this clearly) that they had the operating system running in single user mode but that they wanted to run it in multi-user mode. At that point I was barely 21 years old. I had written a whole bunch of system-level 6502 assembler code and I had a really good ground-up understanding of the way that contemporary computer hardware worked. After studying the manual for the SUN board, I decided that I could simply break the 2MB of physical memory in to 4 chunks of 512KB each and run 4 copies of the operating system, gaining control via interrupts and device drivers.

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#6502 #telesoft #pascal #ada #operating-systems #ucsd-pascal #compiler #ros #renaissance-operating-system #programming #history #computing #programming-languages #sun #intellimac #unix #msx #motorola68000 #68000 #68k #motorola-68k #ibm #stanford #research #memory

բնօրինակ սփիւռքում(եւ մեկնաբանութիւննե՞ր)

New edition of Wirth’s book Project Oberon is out. It describes not only built from scratch software(entire operating system and compiler), but design of the hardware as well.

The vast complexity of popular operating systems makes them not only obscure, but also provides opportunities for “back doors”. They allow external agents to introduce spies and devils unnoticed by the user, making the system attackable and corruptible. The only safe remedy is to build a safe system anew from scratch.

http://www.inf.ethz.ch/personal/wirth/ProjectOberon/index.html

#oberon #wirth #niklaus-wirth #risc #programming #fpga #books #programming-languages #compilers #operating-systems #compiler #freedom #design #security #privacy #surveillance #reliability

բնօրինակ սփիւռքում(եւ մեկնաբանութիւննե՞ր)