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09 Dec 2011
I don't know how to install from .img fi..
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22 Nov 2011
How to install Taj os in my pc. and ..
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21 Oct 2011
TAJ seems to lock up in boot using Bochs..
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Real mode


Real mode as its name suggest is real, that means everything is real in it. The memory which is addressed is real i.e. it really exists at the addressed location. The real mode was put into the processors after 80286 so that they run programs of their predecessor and also for loading the operating system and switching into the Protected mode.

In real addressing mode the memory is addressed by 16bits of addresses. That is you can address at most (2^16=) 1 MB of physical memory.

Memory Structure

Linear Address Range Memory Type Use
0 - 3FF Ram Real-mode Interrupt Vector Table (IVT)
400 - 4FF Ram Bios Data Ares (BDA)
500 - 9FBFF Ram Free Memory (Below 1 MB)   630K
9FC00 - 9FFFF Ram Extended Bios Data Area (EBDA)
A0000 - BFFFF Video Ram VGA Frame buffer
C0000 - C7FFF Rom Video Bios  32K
C8000 - EFFFF Nothing  
F0000 - FFFFF Rom Motherboard Bios 64K