Aaron's Blog

First a loader would read an assembler into main memory and transfer control to it. The assembler then read the user source program and library routines, which generally from punched cards or paper ta

view point of PC Assembly Language by Paul A. CarterInterrupts ---------- external : caused by devices outside the CPU               |              |              |              |              |____

service as a subroutine  Any service except those invoked by hardware interrupts which is called explicitly by an application can be handled this way.service as a process  The process providing

  A difficulty faced by even the earliest systems was initial startup. The CPU could only excute the program in the main memory which is volatile. Thus, the problem was how to get a program into the m

  A shell is a text-based interface between the user and the OS, which is a command interpreter that accepts statements (commands) issued by the user through the keyboard, mouse or other devices. A ty

Abstraction : as extended machinesVirtualization : as virtual machinesResource management : as resource managers