real mode versus protected mode

gregweb16

Does anyone know what the difference is between real mode and protected mode and what it is in reference to/what one needs to know about it for the OS exam?

Also, does anyone know the difference between conventional, extended and expanded memory?

Thanks,
Greg

Plantwiz

For the exam, it won't hurt you to have an understanding, that said, I personally wouldn't invest a large percentage of my time worrying about it.

http://my.execpc.com/~geezer/johnfine/segments.htm

http://www.csee.umbc.edu/~plusquel/310/slides/micro_arch2.html

http://www.webopedia.com/TERM/P/protected_mode.html



http://support.microsoft.com/kb/37242
http://kb.iu.edu/data/aalu.html

http://www.smartcomputing.com/editorial/article.asp?article=articles/1992/jul92/0704/92n0704.asp&guid=

zenzen

disclaimer: i'm probably wrong, just posting what I think they are because I'm not sure either. need someone else's input.


Isn't real mode 16 bit and protected mode 32 bit?

conventional memory is like the first 600 something k of memory, I'm thinking 640.

expanded is the memory over 640k but less than 1mb. I'm not sure if the memory manager utilizes all of this memory or not this is the upper memory area or something, emm386(expanded memory manager/386 processors or something) allows programs to use this and not interfere with eachother

extended is stuff past 1 mb or something, very technical explanation i know


don't take any of this as fact, I'm just offering my very limited understanding maybe we can both get pushed in the right direction