distinguish between physical addresses and logical address?
- 23 Answers
- 77277 Views
- College School Exams Tests, CTS, Infosys, SAX, TATA, TCS, I also Faced
- E-Mail Answers
Answer Posted / salman
An address generated by the CPU is commonly refereed as
Logical Address,whereas the address seen by the memory
unit,that is one loaded into the memory address register of
the memory is commonly refereed as the Physical Address.The
compile time and load time address binding generates the
identical logical and physical addresses.However, the
execution time address binding scheme results in differing
logical and physical addresses.
The set of all logical addresses generated by a program is
known as Logical Address Space,whereas the set of all
physical addresses corresponding to these logical addresses
is Physical Address Space.Now, the run time mapping from
virtual address to physical address is done by a hardware
device known as Memory Management Unit.Here in the case of
mapping the base register is known as relocation
register.The value in the relocation register is added to
the address generated by a user process at the time it is
sent to memory.Let's understand this situation with the help
of example:If the base register contains the value 1000,then
an attempt by the user to address location 0 is dynamically
relocated to location 1000,an access to location 346 is
mapped to location 1346.
The user program never sees the real physical address
space,it always deals with the Logical addresses.As we have
two different type of addresses Logical address in the range
(0 to max) and Physical addresses in the range(R to R+max)
where R is the value of relocation register.The user
generates only logical addresses and thinks that the process
runs in location to 0 to max.As it is clear from the above
text that user program supplies only logical addresses,these
logical addresses must be mapped to physical address before
they are used.
| Is This Answer Correct ? | 5 Yes | 2 No |
Post New Answer View All Answers
What is the difference between cat and more command?
What does the “echo” command do?
What are bash commands?
Why is shebang used?
What is the use of find command in unix?
What is command statement?
What are reported commands?
What is grep and how do you use it?
What difference between cmp and diff commands?
What is nr in awk command?
Which command is used to find whether the system is 32 bit or 64 bit?
What is s and g in sed command?
What is ctrl d?
What is the function of grep command in unix?
What is the use of the tee command?
