Question Paper: System Software : Question Paper Dec 2013 - Computer Science Engg. (Semester 5) | Visveswaraya Technological University (VTU)
0

System Software - Dec 2013

Computer Science Engg. (Semester 5)

TOTAL MARKS: 100
TOTAL TIME: 3 HOURS
(1) Question 1 is compulsory.
(2) Attempt any four from the remaining questions.
(3) Assume data wherever required.
(4) Figures to the right indicate full marks.
1 (a) Bring out the differences between system software and application software.(4 marks) 1 (b) Write programs in both SIC and SIC/XE to copy a character string 'System Software' to another string.(6 marks) 1 (c) Explain the following with reference to SIC/XE machine architecture:
(i) Instruction formats
(ii) Addressing mode
(iii) Data formats
(iv) Register organization
(10 marks)
2 (a) Explain the different data structures used in two pass assembler. Mention clearly their functins in Pass 1 and Pass 2.(6 marks) 2 (b) What is the need of pass 2 assembler? Reason out with a simple example.(4 marks) 2 (c) Generate the object code and complete object program for the following SIC/XE program.

SUM START 0 OPCODES
FIRST LDX #0 LDX -04
LDA #0 LDA -00
+LDB #TABLE2 LDB -68
BSE TABLE2 ADD -18
LOOP ADD TABLE, X TIX -2C
ADD TABLE2, X JLT -38
TIX COUNT STA -OC
JLT LOOP RSUB -4C
+STA TOTAL
RSUB
COUNT RESW 1
TABLE RESW 2000
TABLE RESW 2000
TOTAL RESW 1
END FIRST
(10 marks) 3 (a) With suitable example, explain the use of LTORG assembler directive.(4 marks) 3 (b) Differentiate between program blocks and control sections. Explain how control sections are processed.(8 marks) 3 (c) Discuss how forward reference are handled by multi-pass assembler. Show step by step procedure to evaluate the following statements. Show the symbol table after each scan.
1. NUMB EQU MAXLEN/2
2. MAXLEN EQU BEND-BUF
3. PREVB EQU BUF-1
4. BUF RESB 4096
5. BEND EQU *

Assume the value for location counter as 1034 (H) at line number 4.
(8 marks)
4 (a) Explain with an algorithm the working of an absolute loader.(6 marks) 4 (b) Distinguish between linking loader and linking editor.(4 marks) 4 (c) What are the major data structures required for linkage loader? Write and explain the algorithm for pass 1 of linking loader.(10 marks) 5 (a) What is an interactive editor? List the four tasks performed by document linking process in an interactive system.(4 marks) 5 (b) Explain briefly structure of a typical editor with the help of a block daigram.(10 marks) 5 (c) Discuss briefly the following debugging functions:
(i) Break points
(ii) Tracing
(iii) Trace back
(6 marks)
6 (a) Explain with an example the various data structure required for the design of a macro processor.(8 marks) 6 (b)
SUM MACRO &ID
LDA X&ID?1
ADD X&ID?2
STA X&ID?5
MEND

Expand the following macro invocation statement using the above given macro:
(i) SUM BEETA (ii) SUM A
(4 marks)
6 (c) Explain the advantages and disadvantages of general purpose macro processors.(8 marks) 7 (a) Explain with an example the structure of lex program(8 marks) 7 (b) Define regular expression. Give regular expression for the following
(i) ยท (ii) * (iii) ^ (iv) $ (v) {} (vi) ?
(4 marks)
7 (c) Write a lex program to count the vowels and consonants in given string.(8 marks) 8 (a) What is shift/reduce parsing? Explain the parsing for the string "feed=12+13" using the following grammer.
Statement ? NAME= expression
Expression ? NUMBER + NUMBER / NUMBER-NUMBER
(10 marks)
8 (b) Write a YACC program to recognize the validity of an arithmetic expression that uses +, -, * and /.(10 marks)

Please log in to add an answer.