executing 16 bit pmode code

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jtlb
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executing 16 bit pmode code

Post by jtlb »

How can i do call a 16 bit pmode function from 32 bit pmode with no multitasking? it's for vesa.
thanks
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Brynet-Inc
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Re: executing 16 bit pmode code

Post by Brynet-Inc »

jtlb wrote:How can i do call a 16 bit pmode function from 32 bit pmode with no multitasking? it's for vesa.
thanks
First of all.. "How can i do call a" sounds considerably funny spoken aloud.. :lol:

And I think you might be looking for v8086 mode... :roll:

Really.. Try using the "Search" feature.. The Wiki is a nice place to look as well..

http://www.osdev.org/wiki/Virtual_8086_Mode

(EDIT: Err.. 16bit pmode function? :?..)
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xyjamepa
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Post by xyjamepa »

Also you can go back to real mode setup vesa then back again
to protected mode it's fast and easier than virtual mode.


Thanx.
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Edwin
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Post by Edwin »

To call a 16bit pmode function, i think you need to setup a gdt entry for 16bit pmode and then do a far call to that selector and address of the function.
@Brynet-Inc: I think he is trying to call the pmode interface of the VBE.
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Post by Brynet-Inc »

Edwin wrote:@Brynet-Inc: I think he is trying to call the pmode interface of the VBE.
I see, I had that in my initial response.. I removed it because I wasn't entirely sure about it.

So the VBE protected mode interface refers to 16bit protected mode not 32bit.. I shall make a note of it lol.. :wink:
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Post by inflater »

For example, Windows 3.11, 3.1 and the second mode of 3.0 were in 16-bit protected mode. But take a look to Windows NT 3.51 - it has the same look as good ol' 3.1, and it is 32bit !

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