Tribhuwan University

Institute of Science and Technology

2078

Bachelor Level / First Year / Second Semester / Science

B.Sc in Computer Science and Information Technology (CSC167)

(Microprocessor)

Full Marks: 60

Pass Marks: 24

Time: 3 Hours

Candidates are required to give their answers in their own words as for as practicable.

The figures in the margin indicate full marks.

Section A

Long Answers Questions

Attempt any TWO questions.
[2*10=20]
1.
Explain instruction cycle, machine cycle and T-states. Draw timing diagram of IN instruction with brief description.[10]
2.
Draw block diagram of 80286 microprocessor and explain its main four functional sub-units. Differentiate between Real Address Mode and Protected Virtual address mode.[10]
3.
Explain LXI and CMP instruction. Write an assembly language program for 8-bit microprocessor to divide 8 bit data stored in memory location 8050 by 8 bit data stored in 8051 and store the quotient in 8052 and remainder in 8053.[10]
Section B

Short Answers Questions

Attempt any Eight questions.
[8*5=40]
4.
What are the different modes of parallel communication? Construct a control word for 8255 PPI for following configuration: .a) Port A and Port C_upper = mode 0 .b) Port B and Port C_lower = mode 0 c.) Port A and Port C_upper as input port d.) Port B and Port C_lower as output port [5]
5.
Differentiate between interrupt based I/O and DMA based I/O. Explain based DMA operation in brief. [5]
6.
Differentiate between PUSH and POP instruction with example illustrating the use of these instruction. [5]
7.
Write an assembly language program for 16 bit microprocessor to reverse the string 'This is Microprocessor' [5]
8.
What is the use of $AD_{7}-AD_{0}$ in 8085 microprocessor? Explain address de-multiplexing process in 8085 microprocessor with suitable diagram. [5]
9.
What is mean by addressing mode? Explain all the addressing mode available in 8085 microprocessor. [5]
10.
Explain Register Organization in 80386 microprocessor. [5]
11.
Draw a logic diagram showing generation of memory and I/O read/write control signals in 8085 microprocessor. [5]
12.
Write short notes on (any two):a. Program Counter b. Von-Neumann Architecture c. Interrupt Masking [5]