Microprocessors and Microcontrollers (3160914) MCQs

MCQs of 8051 Interrupts

Showing 21 to 30 out of 33 Questions
21.

The timer generates an interrupt, if the count value reaches to

(a)

00FFH

(b)

FF00H

(c)

0FFFH

(d)

FFFFH

Answer:

Option (d)

22.

The external interrupt that has the lowest priority among the following is

(a)

TF0

(b)

TF1

(c)

IE1

(d)

NONE

Answer:

Option (c)

23.

Among the five interrupts generated by 8051, the lowest priority is given to the interrupt

(a)

IE0

(b)

TF0

(c)

TF1

(d)

RI

Answer:

Option (d)

24.

Among the five interrupts generated by 8051, the highest priority is given to the interrupt

(a)

IE0

(b)

IE1

(c)

TF0

(d)

TF1

Answer:

Option (a)

25.

 All the interrupts are enabled using a special function register called

(a)

interrupt priority register

(b)

interrupt register

(c)

interrupt function register

(d)

interrupt enable register

Answer:

Option (d)

26.

The number of bytes stored on the stack during one operation of PUSH or POP is

(a)

1

(b)

2

(c)

3

(d)

4

Answer:

Option (a)

27.

The step involved in PUSH operation is

(a)

increment stack by 2 and store 8-bit content to address pointed to by SP

(b)

decrement stack by 1 and store 16-bit content to address pointed to by SP

(c)

increment stack by 1 and store 8-bit content to address pointed to by SP

(d)

store 8-bit content to address pointed to by SP and then increment stack by 1

Answer:

Option (c)

28.

The step involved in POP operation is

(a)

decrement stack by 2 and store 8-bit content to address pointed to by SP

(b)

store 16-bit content to address pointed to by SP and decrement stack by 1

(c)

decrement stack by 1 and store content of top of stack to address pointed to by SP

(d)

store content of top of stack to address pointed to by SP and then decrement stack by 1

Answer:

Option (d)

29.

The 8051 stack is

(a)

auto-decrement during PUSH operations

(b)

auto-increment during POP operations

(c)

auto-decrement during POP operations

(d)

auto-increment during PUSH operations

Answer:

Option (d)

30.

After reset, the stack pointer(SP) is initialized to the address of

(a)

Internal ROM

(b)

Internal RAM

(c)

External ROM

(d)

External RAM

Answer:

Option (b)

Showing 21 to 30 out of 33 Questions