pmode <> rmode

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Mastermind

pmode <> rmode

Post by Mastermind »

I have not implemented a reliable V86 monitor yet so I need to switch reliably between real mode and protected mode. How can I exit protected mode so that none of the important stuff gets lost?
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Candy
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Re:pmode <> rmode

Post by Candy »

Mastermind wrote: I have not implemented a reliable V86 monitor yet so I need to switch reliably between real mode and protected mode. How can I exit protected mode so that none of the important stuff gets lost?
disable paging, clear CR0 PE bit and jump far to a realmode segment? wasn't that the 386+ way?
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Mastermind

Re:pmode <> rmode

Post by Mastermind »

What about "unreal mode"? How would I go about setting it from protected mode?
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ASHLEY4

Re:pmode <> rmode

Post by ASHLEY4 »

If you go in to pmode setup a20, gdt ,for 4gb,and then go back to real mode,you are in unreal mode.

ASHLEY4.
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Candy
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Re:pmode <> rmode

Post by Candy »

AFAIK, it was what Ashley said and be sure not to reload your segment registers (except for code).
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