COMPUTER FUNDAMENTALS
1. (a) Convert the following decimal numbers to binary equivalent :
(i) 39.37
(ii) 206.66
Add the numbers given in (i) and (ii) and convert the result into hexadecimal.
(b) Simplify the following Boolean function using four variable Karnaugh's map in
product of sum form :
F(A, B, C, D)=1;(0, 1, 3, 5, 7, 11, 15).
Also, draw the logic circuit for the simplified expression.
(a)Assume rotational speed of a disk is 3600 rpm, the disk has 125 sectors/track
and 512 bytes/sector. What is the data transfer rate and average latency time of the disk system.
(b)What makes the cache memory fast ? Explain different types of mapping techniques used incache memory organisation.
(e) Write the contents of the conditional flags of the flag register of the 8086 microprocessor after subtraction of A and B is performed. Assume value of two 8 bit
numbers A and B are 11001100 and 00111001 respectively.
2. (a) Draw the logic diagram of 3 bit synchronous counter. Also, explain its working.
(b) Define the following terms :
(i) Instruction Register
(ii) Interrupts
(iii) Interface
(iv) Fetch cycle
(v) Multiplexer
(c) Which of the categories of Flynn's 3 classification suits parallel processing. Explain.
3. (a) What are Bit - Slice ALUs ? What is a main advantage of such ALUs.
(b) Explain the following Mnemonics of 8086 Instruction set, with an example of each.
(i) XLAT
(ii) DA A
(iii) CMPS
(iv) ROL and RCL
4. (a) Explain any four addressing modes with the help of an example each.
(b) Explain the functioning of R-S flip-flop. How does J-K flip-flop overcome the
problem of RS flip-flop ?
( c ) Design and Explain an arithmetic pipelining 6 for floating point addition or subtraction. Show with a flow chart.
5. (a) Give at least three differences between each of the following :
(i) Static dataflow and dynamic dataflow computers.
(ii) Multiprocessors with crossbar switch and Multiprocessors with multipost
memory.
(iii) Horizontal micro instructions and Vertical micro instructions.
(b) Explain the problem of cache coherence in multiprocessor system.
( c ) How does synchronisation take place in the multiprocessor system ?
5 .What is the purpose of error detection and correction code ? Explain the process of error correction through Hamming code.
Explain function of following commands :
(i) XLAT
(ii) LEA
(iii) xcHG
(iv) POP
6 . (a) What is meant by assembler directives ? Explain the function of the following directives:
(i) EQU
(ii) ASSUME
(iii) END
(iv) DUP
8. (a) Make diagram and explain pipeline processor.
(b) What is the purpose of addressing modes ? Explain modes in detail.
9. Write a short note on each of the following :
(i) Microprogramming
(ii) Microprogramcounter
(ii| Microinstruction sequencer
(iv) Bit-slice CPU
(v) Hardwired control unit
9 . (a) Write an assembly program to reverse a 6 string stored in data segment. The reversed string should be stored at the same location where the original string was stored.
(b) Convert the BCD number 732.58 to the 4 following :
(i) Binary number
(ii) Octal number
(iii) Decimal number
(iv) Hexadecimal number
( c )Design a combinational circuit that accepts a 4-bit binary number and generates an output '1' only when the input number has odd number of Ts otherwise the output is '0'.
(d) Explain the use of 'IDIV' and 'AAS' 5 instructions with the help of an example of each for 8086microprocessor.
(e) What is the role of a stack in handling the 5 interrupts ? What is the difference between the stack and normal read/write memory.
(f) Explain the Flynn's classification of 4 computers.
10 . (a) Show that NAND gate is a functionally 5 complete set of gates.
(b) Explain the difference between memory 4 mapped I/O and I/O mapped I/O.
(c ) Give an example of the addition of two 6] floating point operands using an arithmetic pipelineshow all the steps involved.
11. (a) What is the need of many addressing modes 5 in a machine ? Give four addressing modes that must be present in a machine. Justify your selection.
(b) What is the need of a control unit ? Explain 6 the basic structure of this with the help of a diagram. Also, give one disadvantage of a hard wired control unit.
(c ) Draw the logic diagram of a master-slave 4 flip flop using R-S flip flop and explain its working.
12. (a) Explain the basic functioning of multiplexer 8 and demultiplexer. Design a circuit of 3 x8 demultiplexer using two 2 x 4 demultiplexer.
(b) Explain any four characteristics of a RISC 7 processor. What are the advantages of using largeregister file ? Explain this with the help of a diagram.
13 . (a) What is a vector instruction ? Explain briefly the need of an array processor in the execution of a vector instruction.
(b) What is cache coherence ? Why is it important for shared memory
multip'rocessor systems ?
( c ) List the differences between :
(i) Constant Angular Velocity and Constant Linear velocity disk.
14.. (a) Perform following subtraction using 2's compfement t
(i) 1101100 - 1011001
(ii) 1100011 - 1100r0
(b) Differentiate between direct and indirect address instruction. How many memory references are required for each type of instruction to bring an , operand into a processor register ? E:<plain.
(c) Write an 8086 assembly language program to contJert a twodtgit BCD number passed in
Aecumulator (AX) to its binary equivalent. I
(d) Simplify the following expression using K-maps in sum of product form :
F (w, x, y, z) = n (5, 10, 12, 13, 14) Also, draw the logic circuit for the simplified
expression.
(e) Convert (3333)n to her<adecimal number.
(fl Draw the logic diagram oI Gbit a.len pari$ checker. Explain its operation with the help of truth table.
15 . (a) How is a RISC processor better than a CISC processor ? Justify 5our answer.
(b) What is the difference between control flour and data flow computers ?
(c) What is the purpose of making data flow graph ? Mahe data flow graph for U = ( A * ( A + B ) - ( A + B ) , z B
(d) Give two differences between decoder and demultiplexer.
16. (a) An 8-bit register Rl contains 10101010. What should the value of the register R2 be such that the most signiticant 4-bits of Rl are
(i) selectivelycleared
(ii) selectively set
(iii) masked
(iv) selec6vely complemented ?
Show the resulting operations.
(b) List {our zubctcles of an instruction cycle. Also list the 'arious micro-operations of these subcycles.
(c) Compare Static RAM with Dynamic RAM.
16. (a) Find the length of SEC code and SEC DED code for the follorvtng 15 bit data sequence :
1010 0101 1010 0101
h) Draw the diagram and explain the working of a JK master slave flipflop. How does its working differ from simple JK flipflop ?
(c) How is an index register related to the auto-increment mode of addressing
17. (a) Why does DMA have priorig over ihe CPU when both requesi a memory transfer ?
(b) Make the logic diagram of a 4-bit serial shift register using JK flipflops. Show the steps to shift the binary number 1101, through this register'
(c) Give an example of the addition of two floating point operands using an arithmetic pipeline'Show all the stens involved.
18 . (c) Write an assembly language (8086) . 7 program to find the total number of
occurrences of the characters 'rsrr and rrrnrl in an array of characters stored in the
memory.
(d) An 8-bit data 1100 1010 is transmitted to a distant location. It is received as 1.110 1010. Explain how SEC code would detect this error.
(e) 'Perform following subtraction using L's complement :
(i) 11001010 10101101
(ii) 10011011 11000111
(f) What are the problems which prevent RISC pipetining to achieve maximum speed?
19. Explain the working of Ripple Counter. Also, draw a 3 bit ripple counter using a
suitable flip flops.
(b) Consider the following code :
a - b - d
b - d * e
c : b + f
Draw the data flow graph for the above equations.
(c) Explain the following addressing modes with an example of each.
(i) Base addressing scheme
(ii) Index addressing
(iit) Stack addressing
(iv) Register addressing
20 (a) Explain the use of 'AAA'&'DAA' instructions with the help of an example
eackr, for 8086 microprocessor.
(b) Draw any two DMA configurations and explain the advantages and disadvantages of these configurations.
.
(c) Design a floating point number format as
per following specifications :
Base : Binary
Mantissa : 20 bit long
Exponent : Cah hold 1gt2a
Find the maximum and minimum value for the proposed presentation. How will zero
be represented in the format propose d by you ? Make suitable assumptions, if any.
21 (a) .Compare any four features of a RISC processor to a CISC processor ?
(b) List four subcycles of an instruction cycle. Also, list the various micro-operations of
any two of these sub cycles.
( c ) Why ROM is considered as a combinational circuit although it is a permanent memory ? How is a ROM will different from that of RAM ?
22.(a) Write a program in 8086 assembly language to multiply two 16 -bit integers.
(b) What is bus arbitration ? Explain the Daisy Chaining and Polling Bus Arbitration
methods with the help of diagrams for each.
(c) What is the need of an interrupt in a computer system ?
23. (a) Simplify the following expression using Karnaugh's map in product of sum form :
F (W, X, Y , Z',)= I (0, 1, 2, 3, 4, 6, 7 , g, g,11, 15) Also, draw the logic circuit for the simplified
expression.
(b) Subtract 1010100 - 1000011 using 2's complernent.
(c) Convert 2222in hexadecimal number.
(d) Write an 8086 assembly language program to convert a 4-digit octal number to its decimal
equivalent
(e) List the registers that are used by the ALU to ,perform various tasksAlso, explain how these registers are used.
(f) What is a cache memory ? Explain about multiple levels of cache.
(g) Differentiate between RISC and CISC architectures.
24. (a) Explain the DMA controller with block diagram. What is meant by a block transfer ?
(b) What are the various phases of an instruction cycle ? Give the micro operation of :fetch and decode phases
Compare Static RAM with Dynamic RAM.
25 .(a) Using NAND gate generate the AND and NOR functions.
(b) What is meant by "addressing mode" ? Explain why the different addressing modes are required. Explain any two addressing modes that need no address field at all. Givg suitable example for each.
( c ) Explain the principles of vector processing. Also, explain various types of vector instructions and their execution.
26. (a) Explain the direct and associative cache mapping.
(b) Write a program in 8086 assembly language to find the user specified number in a list of 15 numbers which is stored in a specific location.
( c ) Write down the method of converting a binary number into its Gray Code equivalent. Also, give an example.
27. (a) Design a 4-bit shift register, which is capable of shifting its binary information in both the directions aloqs with the facility of parallel loading.
(b) Diifferentiate between a hardwired control unit and a micro programmed control unit.
(c) What is the difference between a memory mapped I/O and a peripheral mapped l/O ?
(d) Draw the circuit diagram of RS flip flop and explain its working.
(e) Di fferentiate between MISD and SISD classification of computers as suggested by Flynn.
28. (a) Draw the logic circuit only after simplifying ? the following expression using K-Map:
(b) Convert (1224)s to octal number .
(c) Write an assembly language (8086) . program to find the total number of
occurrences of the characters 'rsrr and rrrnrlin an array of characters stored in the
memory.
(d) An 8-bit data 1100 1010 is transmitted to a 7 distant location. It is received as 1.110 1010. Explain how SEC code would detect this error.
(e) 'Perform following subtraction using L's complement :
(i) 11001010 10101101
(ii) 10011011 11000111
(f) What are the problems which prevent RISC pipetining to achieve maximum speed?
29 . (a) Explain the working of Ripple Counter. Also, draw a 3 bit ripple counter using a
suitable flip flops.
(b) Consider the
a - b - d
b - d * e
c : b + f
Draw the data flow graph for the above equations.
(c) Explain the following addressing modes
with an example of each.
(i) Base addressing scheme
(ii) Index addressing
(iii) Stack addressing
(iv) Register addressing
30 . (a) Explain the use of 'AAA'&'DAA' instructions with the help of an example
eackr, for 8086 microprocessor.
(b) Draw any two DMA configurations and explain the advantages and disadvantages
of these configurations.
(c) Design a floating point number format as per following specifications :
Base : Binary
Mantissa : 20 bit long
Exponent : Cah hold 1gt2a
Find the maximum and minimum value for the proposed presentation. How will zero
be represented in the format propose d by you ? Make suitable assumptions, if any.
31. (a) Compare any four features of a RISC processor to a CISC processor ?
(b) List four subcycles of an instruction cycle. Also, list the various micro-operations of
any two of these sub cycles.
( c ) Why ROM is considered as a combinational circuit although it is a permanent
memory ? How is a ROM will different from that of RAM ?
32. (a) Write a program in 8086 assembly language to multiply two 16 -bit integers.
(b) What is bus arbitration ? Explain the Daisy Chaining and Polling Bus Arbitration
methods with the help of diagrams for each.
(c) What is the need of an interrupt in a computer system ?
