Specifications

Computer Architecture and Maintenance (G-Scheme-2014)

32-bit hardware to mainstream 32-bit computing took 16 years. The first 64-bit PC

processor was released in 2003, and 64-bit computing really didn’t become mainstream

until the release of Windows 7 in late 2009.

Summary

Real Mode

• Like 8086/88 processor

• Use only 16 bit features

• Operates in DOS operation system

• Use only 8086 instruction set

• Uses 16-bit base and offset registers

• Access only 1Mb of physical memory

• All IA-32 processor initialize into real mode

• Concept of segmentation is used.

Protected Mode

• Uses full 32bit feature of the processor

• Process 32 bit instruction

• Can access upto 4Gb of memory

• Uses 32 bit internal registers

• Used by windows , Linux , Os2 operating system

• Concept paging is used

Virtual Real Mode

• Processor runs in protected mode, but simulates real mode: a 20-bit linear

address is translated by paging to a 32-bit physical address.

• A processor is switched to virtual mode when running a DOS application under

Windows operating system.

Q.Difference between real protected and Virtual Mode

Students have to solve the above question

Prepared By – Prof. Manoj.kavedia (9860174297 – 9324258878 ) (www.kavediasir.yolasite.com)