Digital Circuit and Microprocessor MCQs

Question 1

SHIFT LEFT instruction causes all bits shifted one position to the left with rightmost bit set to zero. The effect is to

Accepted Answer

multiply by 2

Answer

divide by 2

Answer

SET the most significant bit

Answer

none of these

Question 2

The selection of a microprocessor for an application is done keeping in mind

Accepted Answer

all of above

Answer

speed compatibility of microprocessor with peripherals

Answer

the time critical behaviour of the application

Answer

the size of program required to implement certain functions

Question 3

The following signal is used when a microprocessor wants to address the memory

Accepted Answer

ALE

Answer

lo/

Answer

Status signals

Answer

HOLD and HLDA

Question 4

The following signal is used when a peripheral device requests the microprocessor to have a DMA operation

Accepted Answer

HOLD and HLDA

Answer

lo/ M

Answer

READY

Answer

RD and WR

Question 5

PROGRAM COUNTER is used to

Accepted Answer

store address of the next instruction to be executed

Answer

store temporary data to be used in arithmetic operations

Answer

store the status of the microprocessor

Answer

none of these

Question 6

The synchronization between microprocessor and memory is done by

Accepted Answer

READY signal

Answer

ALE signal

Answer

HOLD signal

Answer

none of these

Question 7

XOR function can be realised by a minimum of

Accepted Answer

5 NAND gates

Answer

2 NAND gates

Answer

4 NAND gates

Answer

none of these

Question 8

Intel 8080A and 8085A differ in

Accepted Answer

Number of Interrupts

Answer

Number of address lines

Answer

Number of data lines

Answer

Instruction set

Question 9

In 8085 Program Status Word consists of

Accepted Answer

both accumulator and flag

Answer

accumulator contents

Answer

flags

Answer

status bits