Fetrovsky

Is the so called "Unreal Mode" officially supported?

Discussion created by Fetrovsky on Apr 30, 2010
Latest reply on May 16, 2010 by krimo980

Hi, everybody.

I'm doing a bit of research on systems programming, and I came across this unreal or flat real mode, which is set up by switching to protected mode, setting a segment descriptor, and then going back to Real Mode.  I guess I can access a full 32-bit address space by using E*I and E*X registers as pointers.  My question is not so much about whether it works, but mostly if it's intentionally supported in every CPU, and if its support is ever going to be dropped.  Can I write code using it and rest assured that, as long as there is a real mode and a protected mode, my software isn't going to break?

Thanks,

 

- Daniel

 

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