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Using the page table shown below, translate the physical address 25 to virtual address. The address length is 16 bits and page size is 2048 words while the size of the physical memory is four frames. Page Present (1-In, 0-Out) Frame 0 1 3 1 1 2 2 1 0 3 0 -

Using the page table shown below, translate the physical address 25 to virtual address. The address length is 16 bits and page size is 2048 words while the size of the physical memory is four frames. Page Present (1-In, 0-Out) Frame 0 1 3 1 1 2 2 1 0 3 0 - Correct Answer 4121

The correct answer is “option 4”.

CONCEPT:

Virtual Address Space(VAS) is a set of virtual addresses that an Operating System makes available to processes.

Physical Address Space(PAS) is a set of physical addresses in the memory.

Virtual address or logical address is a reference to access the physical memory location by CPU.

The physical address identifies a physical location of data required in memory.

CALCULATION:

Number of pages = VAS ÷  Page size

                     =  216 ÷ 211

                     = 25

PAS =  Number of frames × frame size

        = 4 x 211

        = 22 x 211

         = 213

Physical address  = (25)

= (00 00000011001)

Therefore, according to the page table –

Frame 00 represents page number 2 i.e. (00010)

So, 16-bit Virtual address:

(00010 00000011001) = (4121)

Hence, the correct answer is “option 4”.

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