ISRO CS 2016

Question 11

If 12A7C₁₆ = X₈, then the value of X is

• 224174
• 425174
• 6173
• 225174

Question 12

The Excess-3 code is also called

• Cyclic Redundancy Code
• Weighted Code
• Self-Complementing Code
• Algebraic Code

Question 13

The simplified SOP (Sum of Product) form the Boolean expression (P + Q\' + R\')(P + Q + R)(P + Q + R\')

• (P\'Q + R)
• (P + QR\')
• (P Q\' + R )
• (PQ + R)

Question 14

Which of the following binary number is the same as its 2\'s complement?

• 1010
• 0101
• 1000
• 1001

Question 15

The functional difference between SR flip-flop and JK flip-flop is that

• JK Flip-flop is faster than SR flip-flop

• JK flip-flop has a feedback path

• JK flip-flop accepts both inputs 1

• none of them

Question 16

Consider a non-pipelined processor with a clock rate of 2.5 gigahertz and average cycles per instruction of four. The same processor is upgraded to a pipelined processor with five stages; but due to the internal pipeline delay, the clock speed is reduced to 2 gigahertz. Assume that there are no stalls in the pipeline. The speedup achieved in this pipelined processor is

• 3.2
• 3.0
• 2.2
• 2.0

Question 17

What is the output of this C code?

#include
void main()
{
int k=5;
int *p=&k;
int **m=&p;
printf("%d %d %d",k,*p,**m);
}

• 5 5 5
• 5 5 junk
• 5 junk junk
• Compile time error

Question 18

Consider a disk pack with 16 surfaces, 128 tracks per surface and 256 sectors per track. 512 bytes of data are stored in a bit serial manner in a sector. The capacity of the disk pack and the number of bits required to specify a particular sector in the disk are respectively:

• 256 Mbyte, 19 bits
• 256 Mbyte, 21 bits
• 512 Mbyte, 20 bits
• 64 GB, 28 bits

Question 19

Let the page fault service time be 10 ms in a computer with average memory access time being 20 ns. If one page fault is generated for every 10⁶ memory accesses, what is the effective access time for the memory?

• 21.4 ns
• 29.9 ns
• 23.5 ns
• 35.1 ns

Question 20

Register renaming is done in pipelined processors

• as an alternative to register allocation at compile time
• for efficient access to function parameters and local variables
• to handle certain kinds of hazards
• as part of address translation