250+ TOP MCQs on Stack Structure of 8086/8088 and Answers

Microprocessor Multiple Choice Questions on “Stack Structure of 8086/8088”.

1. The stack pointer register contains
a) address of the stack segment
b) pointer address of the stack segment
c) offset of address of stack segment
d) data present in the stack segment
Answer: c
Clarification: The stack pointer register contains the offset of the address of the stack segment.

2. The stack segment register contains
a) address of the stack segment
b) base address of the stack segment
c) pointer address of the stack segment
d) data in the stack segment
Answer: b
Clarification: The stack segment register contains base address of the stack segment in the memory. The stack pointer register (sP) and stack segment register (SS) together address the stack-top.

3. PUSH operation
a) decrements SP
b) increments SP
c) decrements SS
d) increments SS
Answer: a
Clarification: Each PUSH operation decrements the SP ( Stack Pointer) register.

4. POP operation
a) decrements SP
b) increments SP
c) decrements SS
d) increments SS
Answer: b
Clarification: Each POP operation increments the SP ( Stack Pointer) register.

5. The register or memory location that is pushed into the stack at the end must be
a) popped off last
b) pushed off first
c) popped off first
d) pushed off last
Answer: c
Clarification: The data can be retrieved by POP operation and as in stack, the data that is pushed at the end must be popped off first.

6. In the instruction, ASSUME CS : CODE, DS : DATA, SS : STACK
the ASSUME directive directs to the assembler the
a) address of the stack segment
b) pointer address of the stack segment
c) name of the stack segment
d) name of the stack, code and data segments
Answer: d
Clarification: The directive ASSUME facilitates to name the segments with the desired name that is not a mnemonic or keyword.

7. When a stack segment is initialised then
a) SS and SP are initialised
b) only SS is initialised
c) only SP is initialised
d) SS and SP need not be initialised
Answer: a
Clarification: Though the Stack segment is initialised, the SS and SP pointers must be initialised.

8. The number of PUSH instructions and POP instructions in a subroutine must be
a) PUSH instructions must be greater than POP instructions
b) POP instructions must be greater than PUSH instructions
c) Both must be equal
d) Instructions may be any kind
Answer: c
Clarification: The number of PUSH instructions must be equal to the number of POP instructions.

9. 8086 does not support
a) Arithmetic operations
b) logical operations
c) BCD operations
d) Direct BCD packed multiplication
Answer: d
Clarification: The 8086 microprocessor does not support direct BCD packed operations.

10. For 8086 microprocessor, the stack segment may have a memory block of a maximum of
a) 32K bytes
b) 64K bytes
c) 16K bytes
d) NONE
Answer: b
Clarification: In 8086 microprocessor, the memory segments each have a memory of 64K bytes.