Re: doubt in protected mode

"OS" <baladharma@xxxxxxxxx> wrote in message news:1164194467.094613.89610@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
I have doubt about the memory manager. When i compile any asm
program, it generates
the map file which will contain information about the code segment
,data segment. when i execute
the program, it will copy the code and data to some location in memory
. Now iam jumping to protected mode .

I've long forgotten the details, but there is public domain
code to do this transition. You can do whatever you want
with it:

http://pdos.cvs.sourceforge.net/pdos/pdos/src/protinta.asm?view=markup

There's C code to call it from the same place.

BFN. Paul.


.

Relevant Pages

  • Re: Role of the code segment register during "far" CALLs
    ... EXECUTE, etc and the protection checks happen directly on the page ... So for example a CALL <CoInitialize ... CS register is first used as a selector to retrieve a Segment ... code segment boundaries i presume that the code segment register also ...
    (microsoft.public.win32.programmer.kernel)
  • Re: doubt in protected mode
    ... when i execute ... if the base address for code and data segment is zero and paging is ... Its protected mode address is addressed by the descriptor ... addressing is different between RM & PM. ...
    (comp.lang.asm.x86)
  • Re: Role of the code segment register during "far" CALLs
    ... I see..So that's why every page has permissions such as READ,WRITE, ... EXECUTE, etc and the protection checks happen directly on the page ... CS register is first used as a selector to retrieve a Segment ... code segment boundaries i presume that the code segment register also ...
    (microsoft.public.win32.programmer.kernel)
  • Re: C and Low-level Storage
    ... stored in addressable memory. ... variables in its own code segment, but the claim was that it could ... otherwise it cannot execute it. ... EXECUTE CPU ...
    (comp.lang.cobol)
  • Re: C and Low-level Storage
    ... level storage' and is not the _complete_ thread, started with "drives ... z/OS programmers crazy because they cannot store variable in the code ... variables in its own code segment, but the claim was that it could ... otherwise it cannot execute it. ...
    (comp.lang.cobol)