^ C5808 Pages: 2

Reg No.: Name:

APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY
FIFTH SEMESTER B.TECH DEGREE EXAMINATION, APRIL 2018

Course Code: ೮5305
Course Name: MICROPROCESSORS AND MICROCONTROLLERS (CS, IT)
Max. Marks: 100 Duration: 3 Hours
PARTA
Answer all questions, each carries 3 marks Marks
1 What are the different flag bits available within the flag register of 8086? (3)
2 With the help of a timing diagram show the transition of control signals involved (3)
in the I/O read operation of 8086 in minimum mode.
3 With the help of an example state the differences in the functioning aspects of the (3)
instructions SHR and SAR of 8086.
4 Describe any three addressing modes used in 8086. (3)
PART B
Answer any two full questions, each carries 9 marks
5 Explain the physical and logical memory organization of 8086? (9)
6 What are the different techniques of passing parameters to subroutines in (9)
assembly language programs? Give the detailed description.
7 Write an 8086assembly language program to check whether a string is (9)

palindrome or not. Assume that the string and its length are stored at known
memory locations.

PART C
Answer all questions, each carries 3 marks
8 What are the disadvantages of polling scheme over interrupt scheme? (3)
9 What is an Interrupt Vector Table (IVT)? Provide a diagrammatic representation (3)
of the IVT of 8086.
10 What are the three different I/O modes supported by 8255? (3)
11 What is DMA? State the sequence of operations performed by ೩ DMA controller (3)

in a DMA transfer operation.
PART D
Answer any two full questions, each carries 9 marks
12 With the help of a diagram explain the different blocks of 8259 Programmable (9)
Interrupt Controller.

13 What are the different operational modes of 8279? (9)
14 a) What are the five dedicated interrupts of 8086? (5)

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