Question Paper of CS-64: Introduction to Computer Organisation

Ql(a). Perform the following arithmetic operations using 8-bit register. Use 2’s complement method. Indicate overflow or underflow if it occurs.
(i) 28 + (-28)
(ii) 26 (-26)
(iii) - 38 (90)
(iv) 25 90

(b) Construct the karnaugh’s map for the following function in term of various A, B, C, D. Find the optimal function using this map.

©Describe the need of a multiplexer in a system. How is a multiplexer different j-rom a decoder? Draw a logic diagram of a 2 * 1 multiplexer and 2 * 4 decoder.

(d) Write a program in 8086 to find the largest number in a list of integers stored in the memory. The program should output the number and its locution in the memory.

(e) How does the micro-programmed control unit of a computer function? Explain with the help of a block diagram.

(f) What is the need of having master-slave flip-flop? Example the working of a master-slave flip-flop with the help of logic diagram.

Q2(a). What is a bit slice? Where can it be used? Compare and contrast the features of Random Access to Direct Access. Give an example of Direct Access.

(b) Write a program in 8086 assembly language that compares two strings. The
program will output———1 if string 1 < string 2; 0 if both the stings are equal;
+ 1 if string 1> string 2.

© What is the head of a disk? List the various head mechanisms. Compare and contrast these mechanisms.
are the functional requirements of an I/O module? Explain briefly. Explain the interrupt driven Input/ Output.

(b) What are the advantages and disadvantages of evaluation-stack architecture? Describe the architecture with an example.

© What is the need of having many addressing modes in a machine? As a machine designer, select five most important addressing modes for your machine. Give reasons of your selection.

Q4(a). How is the memory read and write operation carried out using system bus? Write the necessary micro-operations for the above.

(b) Design a floating point number representation for the following:
Base: 2
Mantissa: Normalised
Precision : Single precision
Range of Exponent: 1 X 10�M
Range of mantissa: Equivalent to 5 decimal digits represented correctly
Exponent: Biased exponent
Assume that the word size of the above machine is 16 bits.

© What is firmware? How is it different from software? Describe the Wilkes
control unit.

Q5(a). Compare and contrast unencoded and highly encoded micro instructions.

(b) Write a 8086 assembly program to replace an uppercase letter by a lowercase letter. Make suitable assumptions, if any.

© What is the purpose of the queue in the bus interface unit of 8086 microprocessor?

Q6. Describe the following terms in the context of computer organisation and 8086 micro-processor:

(a) Linker Also called link editor and binder, a linker is a program that combines object
strong>(b) Associative memories
© Co-processor and peripheral processors

(e) Mask and Insert operation

(f)Mapping of cache blocks

Ql (a). Perform the following arithmetic operations using 8-bit register. Use 2’s complement method. Indicate overflow or underflow if it occurs.

(b) Construct the karnaugh’s map for the following function in term of various A, B, C, D. Find the optimal function using this map.
F(A,B,C,D) = ?(2,6,10,14)
Draw the resulting logic diagram of the function.

©Describe the need of a multiplexer in a system. How is a multiplexer different j-rom a decoder? Draw a logic diagram of a 2 * 1 multiplexer and 2 * 4 decoder.

(d) Write a program in 8086 to find the largest number in a list of integers stored in the memory. The program should output the number and its locution in the memory.

(e) How does the micro-programmed control unit of a computer function? Explain with the help of a block diagram.

f) What is the need of having master-slave flip-flop? Example the working of a master-slave flip-flop with the help of logic diagram.