Re: The Linear Address Space

From: Charles A. Crayne (ccrayne_at_crayne.org)
Date: 04/29/04

  • Next message: Cameron Gibbs: "Re: The Linear Address Space" 
    Date: Thu, 29 Apr 2004 06:47:38 +0000 (UTC)

    On Thu, 29 Apr 2004 06:07:14 +0000 (UTC)
    "Cameron Gibbs" <odly@hotmail.com> wrote:

    :Let's forget the distinction between the legacy I/O address space for now.
    :The Address Space *is* all of the addresses that a processor can use!

    The 80x86 hardware makes a clear distinction between physical memory
    address space, and physical I/O address space. The distinction can not be
    forgotten.

    : This would probably also mean that all of the processor registers, the
    :video card registers etc. would all be given addresses.

    Processor registers do not have addresses in either memory address space or
    I/O address space. Video card registers have addresses in I/O space, but
    have display memory addresses in memory address space.

    :Obviously if it is executing it is in RAM and hence doesn't use the Hard
    :Drive sector address and offset so what address does it use?

    It uses address in virtual memory space, which are translated into physical
    address space by the paging mechanism.

    -- Chuck

  • Next message: Cameron Gibbs: "Re: The Linear Address Space"

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