2010 Rajasthan Technical University B.Tech 4 Semester Computer science & engineering "Microprocessor and Interfaces" question paper

Question Paper Details:

University: Rajasthan Technical University
Course: B.Tech Computer science & engineering
Subject: Microprocessor and Interfaces
Exam Year: June 2010
Year or Semester: Second year/ Fourth Semester
Paper Code: 4E2914

Unit-I
           a)      Explain the followings:   [Marks 1*4=4]
      i)                    Tristate Buffer
     ii)                   Decoder
     iii)                 DE multiplexer
     iv)                 Latch
b)      How address and data bus are DE multiplexed using latch in 8085 MPU? Explain with the help of diagram. [Marks 6]
c)       Draw the programming model of 8085 MPU and explain each component in brief. [Marks 6]
OR
            a)      Compare static RAM with Dynamic RAM. [Marks 5]
           b)      Give the format of Flag register in 8085 MPU. Explain each flag by giving suitable example. [Marks 5]
          c)       Describe the functions of following pins in 8085 MPU.
i)                    READY
ii)                   ALE
iii)                 IO/M-
iv)                 HOLD
v)                  INTA (bar)
vi)                 SID                         [Marks 6]
Unit-II
          a)      Explain the operational difference between the following pairs of instructions.
     i)                    SPHL and XTHL
    ii)                   CALL and JMP
   iii)                 INR A and ADI.OIH
   iv)                 DAD Rp and DAA              [Marks 2*4=8]
b)      Draw timing diagram for execution of the instruction “STA 16 bit address”. Assume suitable data and show them in the timing diagram. [Marks 8]
OR
       a)      What do you understand by addressing Mode in 8085? Explain various addressing modes available in 8085 by giving one example of each. [Marks 8]
     b)      Write an assembly language program to load the numbers 8BH and A6H in registers H & L respectively and add the numbers. If the sum is greater than FFH, display OIH at output prot 5: otherwise display the sum. [Marks 8]
Unit-III
     
     a)      Write an assembly language program to generate a delay of 0.4 sec if the crystal frequency is 5MHz. [Marks 4]
    b)      Distinguish between:     [Marks 2*2=4]
        i)                    Maskable and Non maskable interrupts.
       ii)                   Macro & subroutine
c)       With the help of a functional block diagram, explain the organization and working of PIC 8259. [Marks 8]
OR

    a)      Draw the diagram of interrupt structure of 8085 MPU. [Marks 3]
   b)      What is stack? Explain “PUSH PSW” and “POP PSW” instructions with the help of examples. [Marks 1+2+2=5]
  c)       Design a logic circuit t0 interface one EPROM of 8k byte and one RAM of 8k byte with 8085 by giving necessary schematic diagram and showing all essential signals. Compute the address range also for this memory. [Marks 6+2=8]
Unit-IV
      a)      Compare Memory Mapped I/O and peripheral Mapped I/O. [Marks 4]
     b)      Determine the control word if a PPI 8255 is used with port A as output port, port B as input port and Port C is used for handshaking for port A and port B both. [Marks 4]
    c)       Using PIT 8253/8254 realize a square wave generator ( using counter 1) with 1m sec period if the input frequency to 8253/8254 is 1MHz. (write program in assembly language). [Marks 8]
OR
    a)      Explain the formats of control words of PPI 8255 for [Marks 4+4=8]
    i)                    I/O mode 
    ii)                   BSR mode
b)      Explain various command formats available with keyboard/ display interface 8279. [marks 8]
Unit-V

      a)      With the help of a functional block diagram, explain the organization and working of USART 8251. [Marks 8]
    b)      Explain the interfacing of scanned multiplexed display with the help of schematic diagram. [marks 8]
OR
   a)      Differentiate between:                 [Marks 2*2=4]
       i)                    Serial port and parallel port.
      ii)                   Asynchronous and synchronous transmission.
b)      Explain following practical clock circuit required for designing and MPU.
       i)                    Clock circuit using crystal.
      ii)                   RC clock circuit.                                 [Marks 2*2=4]
c)       Explain the interfacing of a 20 key matrix keyboard using port B and port C of the PPI 8255 with the help of schematic diagram. [Marks 8]