ISRO 26th April 2009 Computer Science
1. A full binary tree with n leaves contains?(2N-1)
2. The expression 1*2^3*4^5*6 will be evaluated as?
3. The feature in object oriented programming that follows
he same operation to be carried out differently ,depending on the object, is?
4. The microistructions stored in the control mamory of a
processor have a width of 26 bits. Each microinstructionsion. is divided into
three fields: a microoperation field of 13 bits, a next address field(x), and a
MUX select field(y).There are 8 status bits in the inputs of the MUX. How many
bits are there in the X and Y fields, and what is the size of the control memory
in number of words?
5. A cpu has 24-bit instructions. A program starts at
address 300(in decimal).Which one of the following is a legal program counter
(all values in decimal)?
6. Consider a disk pack with 16 surfaces,128 tracks per
surface and 256 sectors per track.512 bytes of data are stores in a bit serial
manner in a sector.The capacity of the disk and the number of bits required to
specify a particular in the disk are respectively.
7. Consider a pipelined processor with the following four
ID:Instruction Decode and Operand Fetch EX:Execute WB:Write
The IF,ID and WB stages take one clock cycle each to complete the operation.The
ADD and SUB instructions need 1 clock cycle and the MUL instruction need 3 clock
cycles in the EX stage.Operand forwarding is used in the pipelined
processor.What is y the number of clock cycles taken to complete the following
sequence of instructions?
ADD R2,R1,R0 R2 R1+R0
MUL R4,R3,R2 R4 R3+R2
SUB R6,R5,R4 R6 R5+R4
8. The use of multiple register windows with overlap causes
a reduction in the number of memory accesses for:-
1.Function locals and parameters
2.Registers saves and restores
9. A processor that has carry, overflow and sign flag bits
as part of its program status word(PSW) performs addition of the following two
2’s complement numbers 0100101 and 11101001.After the execution of this addition
operation, the status of the carry, overflow and sign flags, respectively will
10. The two numbers given below are multiplied using the
Multiplicand:0101 1010 1110 1110 Multiplier:0111 0111 1011
1101 How many additions/Subtractions are required for the multiplication of the
above two numbers?
11. The addition of 4-bit, two’s complement,binary numbers
1101 and 0100 results in
12. Which of the following statements about relative
addressing mode is FALSE?
1.It enables reduced instruction size
2.It allows indexing of array element with
3.It enables easy relocation of data
4.It enables f asters address calculation
than absolute addressing
13. Substitution of values for names(whose values are
constants) is done?
14. A root alpha (symbol) of equation f(x) =0 can be
computed to any degree of accuracy if a ‘good’ initial approximation x0 is
chosen for which?
15. Which of the following statement is correct?
Ans.delta(Uk Vk)=Uk+1 delta Vk+Vk+1 delta Uk