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Dear Students,

The new semester brings you the combo pack of SE and ISD in a comprehensive integrated contagious and addictive package packed in the dungeons of Roland that is bound to send a chill down your spine and a smile wide across your faces. Here is the first draft of contents of the combined package.


Enjoy reading and “Suggestions” always welcome!!!

Banking services for long stayed as royal service. After the advent of the private banks things have gotten murkier. My recent experiences are quite disappointing.

  1. I tried to open an account at the ICICI Bank. The bank requires a MAQB of 10000/- . If the balance falls below the limit a penalty will be there. So are they providing the services for free? NO. Just count a difference between the interests of fixed and SB and add the hassle of not being able to remove the money while avoiding penalty and you get what is the charge for keeping an SB account with them. I Give Up!
  2. A Credit Card enquiry revealed that UTI Bank takes a deposit of 25000/- to issue a credit card and the credit limit is upto 80 percent of it. So if I take a Credit card, I will be given credit from the money which I already own. What a joke! Do I stand a chance to bear this?
  3. At SBI an account opening form revealed that they not only require my details but also ages of all in my family along with details of any relatives settled abroad. That is not all, they also require all loans credit cards etc availed by me along-with asset list like whether I live in an ancestral house or rented house, if I possess any vehicles, if I have made any life insurance or any investments . . . Possibly the most ridiculous from all is that they also need the educational qualification of my spouse. Does it not feel that they are asking for too much for keeping my money safe?
  4. The Core Banking of Parlakhemundi SBI is somewhat misleading. As they have not made the signatures digital, cheques cannot be used at any other branch. I seriously suspect that they are verifying signatures for withdrawal slips and cheques at the home branch too. It is nothing short of horrble practice.

If you have experinced the Royal Indian Banking Experience then you know that there is more to it. Don’t you agree?

Q h 7thECE2006

A logical address space of 12 pages of 1024 bytes each mapped to a physical memory of 64 frames. What would be the minimum number of bits in logical address?

Q i 7thECE2006

What would be the minimum number of bits in physical address?

Q 2 7thECE2006

A demand paged virtual system has the following parameters

  1. Time to serve page faults:
    • When a new frame is allocated: 12 mili seconds
    • When a modified page is replaced: 20 mili seconds
  2. Memory access time: 200 nano seconds
  3. While serving a page fault:
    • Probability of allocating a new frame: 30%
    • Probability of allocating a modified frame: 70%

Find the maximum page fault rate such that degradation in memory access time is not more than 20%.

From Prof. Anthony D. Joseph

  1. Which of the following instructions should be allowed only in kernel mode?
    1. Disable all interrupts
    2. Read the time-of-day clock
    3. Set the time-of-day clock
  2. Five jobs are waiting to be run. Their expected running times are 9, 6, 3, 5, and X. In what order should they be run to minimize average response time? State the scheduling algorithm that should be used AND the order in which the jobs should be run. (Your answer will depend on X)
  3. Consider a system that starts with a total of 150 units of memory, which is then allocated to three processes as shown in the following table of processes, their maximum resource requirements, and their current allocations:
    Process    Max Demand    Currently Holds
    P1           70                  45
    P2           60                  40
    P3           60                  15
    P4           60

    Determine whether it would be safe to grant each ofthe following requests. If YES, give an execution order that could be guaranteed possible. If NO, show the resulting allocation table.

  4. Evaluate the Banker’s algorithm for its usefulness in real life. Give at least two reasons to justify your choice.

The Embedded Battle

Today the PECS 3405 EMBEDDED SYSTEMS paper was over.
Most of the short questions were good; albeit some difficulties in the
longer siblings.

  1. Shorts
    1. List down various hardware and software resources in an embedded computer system.
    2. Why the response time of LINUX is lower that WINDOWS operating system? <<Grammatical Error
    3. What are the parameters used to characterize a real time task?
    4. The performance of hierarchical memory system is faster. Why?
    5. Why embedded systems are realized as real time systems?
    6. Distinguish between hard, soft and firm real time systems?
    7. Distinguish between periodic, aperiodic and sporadic tasks in a RTOS.
    8. List down at least three tools that support the design and development of embedded system.
    9. What do you mean by release time and response time of real-time tasks?
    10. List down various hardware and software drivers used in an embedded system.
  2. Long
    1. Explain the relationship between operating system, computer hardware, system software in an embedded system with the help of a schematic diagram. [4]
    2. What is a system call? Explain the uses of system call in embedded system with an example. [4]
    3. The system calls are implemented as interrupt service routines. Justify. [2]
  3. Long
    1. What do you mean by interface synthesis? Illustrate how the communication time requirements are estimated using process-resource mapping and architectural inputs. [4]
    2. Describe a set of native communication application program interfaces in JAVA for the communication between JAVA and the system-on-chip. [6]
  4. Long
    1. What are various criteria to be considered for processor scheduling in an embedded system? Explain various types of processor scheduling policies with examples. Which of these is followed in LINUX operating system. [5]
    2. Five batch jobs A through E, arrive at a computer center at almost the same time. They have estimated running time of 10, 6, 2, 4 and 8 minutes. Their (externally determined) priorities are 3, 5, 2, 1 and 4 respectively, with 5 being the highest priority. For each of the following algorithms determine the mean process turn-around time, ignore process switching overhead: [5]
      1. Round Robin – assume that the system is multi-programmed and that each job gets its fair share of CPU.
      2. Priority Scheduling – assume that only one job at a time runs, until it finishes. All jobs are completely CPU bound.
      3. First come, first served (run in order 10, 6, 2, 4, 8 ) – ditto –
      4. Shortest job first – ditto –
  5. Long
    1. Discuss the role of tools for the development and debugging of embedded systems. What do you mean by run-control debugging and field debugging. [4]
    2. How does the response time is affected by enabling/disabling interrupts in every kernel service call in a real-time operating system? [3]
    3. Discuss the types of interrupts in embedded C. [3]
  6. Long
    1. A virtual memory system has an address space of 8k words, a memory space of 4k words and page and block sizes of 1k words. The following page reference changes occur during a given time interval. (Only page changes are listed, if the same page is referenced again, it is not listed twice). 4 2 0 1 2 6 1 4 0 1 0 2 3 5 7 Determine the four pages that are resident in main memory after each page reference change if the replacement algorithm used is (i)FIFO (ii)LRU. [5]
    2. Disk requests come into the disk driver for cylinders 10, 22, 20, 2, 40, 6 and 38 in that order. A seek takes 6 msec per cylinder moved. How much seek time is needed for (i) First come, first served, (ii) Closest cylinder next, and (iii) Elevator algorithm (initially moving upward). In all cases the arm is initially at cylinder 20. State advantages and disadvantages for each methods. [5]
  7. Long
    1. Explain briefly different real time operating systems with examples. [4]
    2. What is the primary goal of a real-time operating system? [2]
    3. Why round-robin scheduling policy is appropriate for time-sharing operating systems? Explain with example. [4]
  8. Long
    1. Explain the interprocess communication mechanisms in LINUX. [4]
    2. Discuss the message-based interprocess communication in embedded real-time systems and its appropriate operating system support. [3]
    3. How an optimized communication mechanism can be obtained using message-based interprocess communication. [3]

What do you think?

In the coming odd semesters we are faced with a serious problem. The problem is more philosophical than implementational.

There are two papers in the elective list which has licked away our brains. Not that we are biased for any or we are less in manpower but the matter is more about our students. This batch is one of the best as I have encountered in terms of attention in the class, eagerness to learn and imagination. However that is one of our strengths and it also creates a kind of weakness not to let them down at any cost.

Advanced Operating System is a very good course and students from computer science branch should study it as it would expose them to higher understanding in to the behaviour of OS and its links with the Computer Architecture. The prescribed book Milankovic is a bit quirky though it can be learned in the class.

Information Systems Design is a course which is designed to prepare the students for software projects. You can think that both Software Engineering and Information Systems Design are the theories and Project Lab is the experimentation for these theories. This effectively makes ISD the most important course for any budding software engineer. However there is a twist to the story. There is a compulsory course Software Engineering already in the syllabus. SE and ISD share some parts of the theory but they are not the same wine in two bottles thing. They have many things which are not in common. ISD is mainly software project oriented where as SE shows much a bigger prospective. SE is very wide whereas ISD is very focused.

Having said this, Learning AOS will be getting in touch with an advanced set of OS underpinnings. Whereas ISD opens up a vista of commercial Software Designing practices for the student. AOS targets core computing whereas ISD targets the business software market. Both have their strengths. If SE and ISD were in different semesters possibly there would be no place for arguments but their presence in a single semester is what creates the dilemma.

It is no denying that SE and ISD are similar to a certain extent and share some chapters. So in a single semester there would be repetition of the same concepts for two courses. This effectively translates to easy exam preparation for students who can put a bit extra into SE and master ISD.

In the contra opinion, OS is my favourite subject so I personally would like to offer AOS to my students but my recent rendezvous with OS was not very satisfactory (I have already indicated in my previous post) so if students can’t offer sufficient time for courses then they will be in a real nasty problem. 7th semester will certainly have less time because of frequent campus-placement related activities. It is beyond doubt that we will surely finish the course in the class but if I have to teach only the chalk-board (when most students are absent) then this is pure wastage of AOS and a terrible nightmare for students for their 7th sem exams who has to tear out their hair at the last moment before exams.
Finally with a heavy heart we are offering the course twins, SE and ISD and dropping all our plans about offering AOS, as for every one student who can get into the AOS we can isolate two who will find it even more easier to digest ISD. Whatever we decide will be for the better for all our students, not a couple of brilliant exceptions. The debate will go on possibly till the end of the exams.

— Crack your brains with this issue post rants if you feel like —

Yesterday at-least four of my students rang me up for their doubts. It is not unnatural but the stride of their studies are quite disturbing. Approximately after 10 classes from start of the semester, they got themselves indulged in the placement spree. Nevertheless, classes were missed. They made it a custom to miss the day previous to the placement day albeit for preparations; the d’ day for competition and the following day to take rest.

Not to overemphasize, they lost oodles of classes. Now as BPUT started to hammer their heads with the exam time table, they are realizing now what has passed out!

If this much would have been the story then it would have been fine. Still to come; the shock!

A couple of days back I took an abandoned class in the pack-slotted extra classes schedule. To my horror, only a few students were there. From the list of the absentees were many notable faces:-

The CEO of PriyaZeem Productions, The specific students who had handed me problems to solve, regular absentees … -Oh my God! with approx ~10 students I started the discussion.

If they miss regular classes, drop extra classes, whack the class test, what is in store is only a matter of plain guess!

May God Help Them. (Tathastu, Amen, Zumma-ameen)

Hello Everybody!

The past few weeks were spent on thinking to obtain a blog or not when I own a personal website. But I found editing it to be too painstaking. So I am embarking upon setting this WordPress entry as an extension to my work. After the bad experience with Blogspot possibly this was the only place I could have come.

We will meet soon.