abhimanyu projects
Jan 01, 2013 Posted by Abhimanyu


Jan 01, 2013 Posted by Abhi Raj

1)      Define transfer function.
2)      What are the basic elements used for modeling mechanical rotational system?
3)      Name two types of electrical analogous for mechanical system.
4)      What is block diagram?
5)      What is the basis for framing the rules of block diagram reduction technique?
6)      What is a signal flow graph?
7)      Write Definitions /Short Notes on:
  1. System
  2. Control System Reference Input
  3. Output
  4. Feedback element
8)      Classify Control system.
9)      Differentiate between Open Loop and Closed Loop Control System.
10)  Explain importance of Feedback system.
11)  Write the rules of Block Diagram Reduction.
12)  Explain Mason’s Gain Formula.
13)  Write the differential equations governing the Mechanical system shown in fig. and determine the transfer function.

14)  Determine the transfer function Y2(S)/F(S) of the system shown in fig.

15)  Find the overall gain of the system whose signal flow graph is shown in fig.
16) Draw a signal flow graph and evaluate the closed loop transfer function of a system
      Whose block is shown in fig?
17) Derive the expressions and draw the response of first order system for unit step input.
18) Draw the response of second order system for critically damped case and when input is unit step.
19)  Derive the expressions for Rise time, Peak time, and Peak overshoot. A potential control system with velocity feedback is shown in fig. What is the response of the system for unit step input?

20) For a unity feedback control system the open loop transfer function
G(S) = 10(S+2)/ S2 (S+1). Find
(a) Position, velocity and acceleration error constants.
(b) The steady state error when the input is R(S) where R(S) =3/s –2/s2+1/3s3
21) What is frequency response?
22) What are advantages of frequency response analysis?
23) What are frequency domain specifications?
24) Define Resonant Peak.
25) What is resonant frequency?
26) Define Bandwidth.
27) What is cut-off rate?
28) Define gain margin.
29) Define phase margin.
30) What is phase and Gain cross-over frequency?
31) What is Bode plot?
32) Define corner frequency.
33) What are the advantages of Bode Plot?
34) Sketch the Bode plot and hence find Gain cross over frequency, Phase cross over frequency, Gain margin and Phase margin.
G(S) = 0.75(1+0.2S)/ S (1+0.5S) (1+0.1S)
35) Sketch the polar plot for the following transfer function and find Gain cross over frequency, Phase cross over frequency, Gain margin and Phase margin.
G(S) = 400/ S (S+2) (S+10)
36) What is the necessary and sufficient condition for stability?
37) What is routh stability condition?
38) What is Nyquist stability criterion?
39) Using Routh criterion determine the stability of the system whose characteristics
equation is s4+8s3+18s2+16s+5 =0 .
40) Construct Nyquist plot for a feedback control system whose open loop transfer function is given by G(S)H(S) =5/ S(1-S).comment on the stability of open loop and
closed loop transfer function.
41) Sketch the Nyquist plot for a system with the open loop transfer function
       G(S)H(S) =K(1+0.5S) (1+S) / (1+10S) (S-1).determine the range of values of K for which the system is stable.
42) What are state variables?
43)  What is the state space?
44) What are phase variables?
45) What is a state vector?
46) Test the controllability & observability of the system whose state space representation is given as,
47) Determine the state variable representation of the system whose transfer function is
given as Y(s) / U(s) = 2s2+8s+7 / (s+2) 2 (s+1)


Jan 01, 2013 Posted by Abhi Raj

Q1. Write a program to turn on and turn off the light for every 2 seconds. Use data bit D4 to operate the light. Also show the delay calaculation and assume system frequency 5Mhz.
Q2. Write a program to generate the square wave with a 200µs on period and 400µs off period. Also show the delay calaculation and assume system frequency 2Mhz.
Q3. Write a program to:
a)      Clear the accumulator.
b)      Add 45H
c)      Subtract 90H
d)     Add 64H
e)      Display the results after subtracting and after adding 64H.
Specify the answers you would expect at the output ports.
Q4.Write a program to load the bit pattern 91H in register B and 87H in register C. Mask all the bits except D0 from the registers  B and C. If D0 is at logic1 in both registers, turn on the light connected to the D0 position of output port 01H; otherwise, turn off the light.
Q5. A set of eight data bytes is stored in memory location starting at XX50 H. Write a program to check each data byte for the bits D7 and D0. If D7 or D0 is 0, reject the data byte; otherwise, store the data bytes at memory locations starting at XX60hH.
Data(H) : 80,52,E8,78,67,35,62, F5
Q6. A set of eight data bytes is stored in memory location starting at XX50 H. Write a program to check whether a byte 40H exist in the set. If it does, stop checking and display its memory location; otherwise output FF H.
Data (H) : 48,32,F2,38,37,40,82,8A
Q7. Six bytes of data are stored in memory locations starting at XX60H. Write a program to add all data bytes. Use register c to save any carries generated, while adding the data bytes. Display the entire sum at two output ports.
Data (H): A2,54,A2,86,5B,25
Q8. Draw the flowchart to load the hexadecimal numbers 90 H and A5 H in registers D and E respectively and add the numbers. If the sum is greater than FFH, display 01H at port 0; otherwise, display the sum.
Q9. Write a program to provide the given on/off time to three traffic lights (Green, Yellow and Red) and two pedstrain signs(WALK and DON’T WALK). The signal lights and signs are turned on/off by the data bits of an output port as shown below:
Data Bits
On Time
1.      Green
20 seconds
2.      Yellow
10 seconds
3.      Red
20 seconds
4.      WALK
20 seconds
5.      DON’T WALK
30 seconds
The traffic and pedestrain flow are in the same direction; the pedstrain should cross the road when the Green light is on.
Q10. Write a program to control a railway crossing signal that has two alternately flashing red lights, with a 1 second delay on time for each light.
Q11. Write a 20ms time delay subroutine using register pair BC. Clear the Z flag without affecting any other flags in the flag register and return to the main program.
Q12. Write a program to add the two hex numbers 7A and 46 and to store the sum at memory location XX98H and the flag status at location XX97H.
Q13. An 8bit binary no. is stored in memory location XX50H. Write a program to transfer the byte to the accumulator and Separate the two nibbles. Also call the subroutine to convert each nibble into ASCII hex code and Store the codes in memory location XX60H and XX61H.
Q14.  A BCD no. between 0 and 99 is stored in an R/W memory location called the input buffer (INBUF). Write a main program and a conversion subroutine (BCDBIN) to convert the BCD no. into its binary equivalent.  Store the result in a memory location defined as the output buffer (OUTBUF).
Q15. A set of six unpacked BCD no. is stored in memory locations starting at XX30 H. Assume the seven segment codes of the digits  0 to 9  for common cathode LED are stored in memory location starting at XX70 H. Write a program to select an appropriate seven segment code for each digit. The code should be stored in memory location in reverse order starting at XX90 H.

Q16.Calculate the delay in the following loop, assuming the system clock period is 0.5microseconds:
                                    LXI B, 12FF H      10
                  DELAY:   DCX B                   6
                                   XTHL                     16
                                   NOP                        4
                                   MOV A, C              4
                                   ORA B                    4
                                   JNZ DELAY           10/7

Q17. A set of ten packed BCD no. is stored in memory location starting at XX40 H.
i) Write a program to add these numbers in BCD. If a carry is generated save it in register B and adjust it for BCD. The final sum will be less than 9999BCD .
ii) Write a second subroutine to unpack the BCD sum stored in register A and B and Store them in the memory location starting at XX60 H. (MSB at XX60 H and LSB at XX63 H)
  Q18. With reference to Q17. Write a subroutine to convert the unpacked BCD digits stored at XX60 to XX63 H into ASCII code and store them at output buffer memory starting at XX80 H.       
Q19. Write a program to subtract two packed BCD numbers (75- 36) stored in register B and C respectively. The minuend is placed in register C and subtrahend is placed in register B. Display the result at output port 0.
Q20. A binary number is stored in memory location XX50 H. Convert the no. into BCD and store each BCD as two unpack BCD digits in the output buffer (XX70 H). to perform the task, write a main program and two subroutines: one to supply powers of 10 and the other to perform the conversion.