Engineering Questions with Answers - Multiple Choice Questions
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Microprocessors MCQ – Protected Virtual Address Mode (PVAM) -1
The procedure of fetching the chosen program segments or data from the secondary storage into the physical memory is
a) mapping
b) swapping
c) unswapping
d) pipelining
View Answer
Answer: b
Explanation: Swapping is the procedure of fetching the chosen program segments or data from the secondary storage into the physical memory.
The procedure of storing back the partial results on to the secondary storage is called
a) mapping
b) swapping
c) unswapping
d) pipelining
View Answer
Answer: c
Explanation: The procedure of storing back the partial results or data back on to the secondary storage is called unswapping.
The ability of 80286 to address the virtual memory per task is
a) 1MB
b) 1GB
c) 1TB
d) none of the mentioned
View Answer
Answer: b
Explanation: The 80286 is able to address 1Gbyte of virtual memory per task.
The branch instructions are handled by
a) swapping mechanism
b) unswapping mechanism
c) operating system
d) all of the mentioned
View Answer
Answer: d
Explanation: The handling of branch instructions like JUMP and CALL is taken care of, by the swapping and unswapping mechanism, and operating system.
A descriptor contains information of
a) program segment
b) page
c) regarding segment and its access rights
d) all of the mentioned
View Answer
Answer: d
Explanation: The segments or pages have been associated with a data structure known as a descriptor. The descriptor contains information on the page, and also carry relevant information regarding a segment, and its access rights.
The descriptors that are used for subroutines and interrupt service routines are
a) data segment descriptors
b) gate descriptors
c) code segment descriptors
d) system segment descriptors
View Answer
Answer: b
Explanation: For data segment, the corresponding descriptor may be data segment descriptor and for code segment, there may be code segment descriptor. For subroutines and interrupt service routines there are gate descriptors.
A segment with low privilege level is not allowed to access another segment of
a) low privilege level
b) high privilege level
c) low and high privilege level
d) none of the mentioned
View Answer
Answer: b
Explanation: A segment with low privilege level is not allowed to access another segment with high privilege level.
A descriptor is used to carry out
a) transfer of control
b) task switching
c) to store privilege level and segment limit
d) all of the mentioned
View Answer
Answer: d
Explanation: A descriptor is used to carry out additional functions like transfer of control and task switching.
The descriptor that is used for special system data segments and control transfer operations is
a) data segment descriptors
b) gate descriptors
c) code segment descriptors
d) system segment descriptors
View Answer
Answer: d
Explanation: The 80286 has system segment descriptor, that is used for special system data segments, and control transfer operations.
A code segment descriptor contains
a) 16-bit segment limit
b) 24-bit segment base address
c) 8-bit access rights byte
d) all of the mentioned
View Answer
Answer: d
Explanation: A code or data segment descriptor contains 16-bit segment limit, 24-bit segment base address, 8-bit access rights byte and the remaining 16-bits are reserved by Intel for upward compatibility.
In access rights byte, if P (Present)=1, then the segment is mapped into
a) physical memory
b) virtual memory
c) no mapping takes place
d) none of the mentioned
View Answer
Answer: a
Explanation: If P=1, then the segment is mapped into physical memory.
In access rights byte, to select system segment descriptor, the condition is
a) S=1
b) S=0
c) S not equal to zero
d) none of the mentioned
View Answer
Answer: b
Explanation: If S (segment descriptor)=0, then system segment descriptor or gate descriptor is selected.
If S (segment descriptor)=1, then the descriptor selected is
a) code segment descriptor
b) data segment descriptor
c) stack segment descriptor
d) all of the mentioned
View Answer
Answer: d
Explanation: If S=1, then code or data (including stack) segment descriptors are selected.
The memory of limit field is
a) 2 bits
b) 4 bits
c) 8 bits
d) 16 bits
View Answer
Answer: d
Explanation: The limit field, which is the maximum allowed offset address, is of 16 bits.