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The bits for this portion of the logical address are not translated (given power of two page size). The logical (virtual) page number is number of (virtual) page counting from zero. I.e., $$\frac{logical\_address}{page\_size}$$ As you noted, the physical page is determined by the translation table, indexed using the logical (virtual) address.
Physical address is the precise location of data in computer memory and logical address is a virtual address that a computer program uses to access memory. While newer processors seamlessly handle both physical and logical addresses, older ones like the Intel 8080/8085 directly generates physical addresses.
While studying about memory management, paging and segmentation there is a lot of usage of phrases like CPU generates logical addresses and logical addresses are converted to physical addresses etc. I know that the term physical address refers to actual RAM, but I do not have clear idea about what logical address is and where does it reside.
Logical address includes both page number and the offset within the page. Your logical address is 16 bit. Page size as mentioned is 256 = 2 8. It means that 8 bit address is necessary to address any word within the page. The least significant 8 bits are used for this purpose (as offset address)
So there are 2^22 logical address frames. The physical memory is 2^25 bytes and the frame size is 2^10 bytes. So the number of frames in the physical address space is (2^25)/(2^10) = 2^15. Each process has its own logical address space. That may be smaller than the physical address space. But at a given time there are more than one process running.
Consider the page table below (all numbers are in hex) and assume 1 KB page size. Assume 16-bit logical address and 20-bit physical address. a.What are the page numbers and offsets for the following logical addresses: 1.1CC4 2.3A98 3.43FC 4.600C 5.2BD0 6.0. b.provide the physical address for each part a: I figured out part a. I'm stuck on part b.
Since the question asked is to find the logical address, it follows that the thing given (0xABCD) is the physical address, the one obtained after translation. Let's convert the address given to binary, and then split the address as prescribed in the question: 6 bits for page id, 10 bits for offset.
215201 is logical address space provided to us which means it is a process size. 1 KB is page size which is equivalent to 2^10 or 1024 Bytes. Process divided by page size gives a quotient and remainder, 215201/1024 = 210 quotient which is number of pages and 161 as a remainder which is offset.
Definition of Logical address: A logical address or virtual address is an address that is generated by the CPU during program execution. - afteracademy. Definition of Physical address: physical address refers to a memory address or the location of a memory cell in the main memory - Techopedia
What is often possible is to have used logical address space that is at random places within that 64 bit space; this can be used to prevent attacks from hackers because they cannot know where in that huge logical space your data is. (So for example malloc might return addresses anywhere in the 64 bit space, but only for a total of say 64 GB of ...