Physical memory layout when the processor is in REAL MODE

As i promised earlier we will discuss the pictorial view of the physical memory layout in real mode. We need to keep in mind that this physical memory layout is totally different from the virtual/linear memory layout either in kernel mode or user mode processes.

The linear address space of a process is divided into two parts:
Linear addresses from 0x00000000 to 0xbfffffff can be addressed when the
process is in either User or Kernel Mode.

Linear addresses from 0xc0000000 to 0xffffffff can be addressed only when
the process is in Kernel Mode.

-- We will discuss on this topic later in details.--

Lets try to visualize the physical memory layout:
---------------------------------------------------------------------------------

1 Mb = 0x10000:0000

1 Mb-1 = 0xFFFF:000F End System BIOS area
960 Kb 0xF000:0000 | = 128 Kb
896 Kb 0xE000:0000 Start System BIOS area

896 Kb-1 = 0xDFFF:000F End Expansion card BIOS area
832 Kb 0xD000:0000 | = 128 Kb
768 Kb 0xC000:0000 Start Expansion card BIOS area

768 Kb-1 = 0xBFFF:000F End Video RAM
704 Kb 0xB000:0000 | = 128 Kb
640 Kb 0xA000:0000 Start Video RAM

640 Kb-1 = 0x9FFF:000F| Working RAM LIMIT ENDS
576 Kb 0x9000:0000 |
512 Kb 0x8000:0000 |
448 Kb 0x7000:0000 |
384 Kb 0x6000:0000 |
320 Kb 0x5000:0000 | = 640 Kb
256 Kb 0x4000:0000 |
192 Kb 0x3000:0000 |
128 Kb 0x2000:0000 |
64 Kb 0x1000:0000 |
31Kb 0x07c0:0000 |-->>07C0:0 Boot code is loaded here.
0 Kb 0x0000:0000 | Working RAM LIMIT start +System information like
(Interrupt vector table)

To know more about BIOS service routine table(i.e. Interrupt vector table) click on the following link.
!!URL!!
http://bioscentral.com/misc/biosservices.htm

If you guys have any queries do let me know , else i will think more on this memory layout and if i found something interesting i will discuss it here.

Good night to all of you.. Going to sleep now ....