DipIETE – ET/CS (NEW SCHEME)   –   Code: DE60/DC68

 

Subject: MICROPROCESSORS & MICROCONTROLLERS

Flowchart: Alternate Process: JUNE 2010Time: 3 Hours                                                                                                    Max. Marks: 100

 

 

NOTE: There are 9 Questions in all.

·      Question 1 is compulsory and carries 20 marks. Answer to Q.1 must be written in the space provided for it in the answer book supplied and nowhere else.

·      Out of the remaining EIGHT Questions, answer any FIVE Questions. Each question carries 16 marks.

·      Any required data not explicitly given, may be suitably assumed and stated.

 

 

Q.1       Choose the correct or the best alternative in the following:                                  (210)

       

             a.  Convert  to binary representation.  Choose one answer among the following which is nearest to the value.

 

                  (A) 11001.00101                                 (B) 11001.00010

                  (C) 11101.00010                                 (D) 11101.00110

 

             b.  The XCHG instruction in 8085 microprocessor after execution exchanges the data between  

 

                  (A) BC & HL register pair                    (B) AB & CD register pair

                  (C) DE & HL register pair                    (D) AB & HL register pair

 

             c.  The instruction JPO means jump on   

 

                  (A) overflow                                         (B) odd parity

                  (C) positive                                          (D) zero

 

             d.  DAA instruction is executed to correct result after

 

                    (A) DMA                                           (B) BCD subtraction

                  (C) Burst data transfer                          (D) BCD addition

 

             e.  TRAP is a

 

                  (A) Data transfer instruction                  (B) Jump instruction

                  (C) Non-maskable interrupt                  (D) Maskable interrupt

 

             f.   The control word of 8255 PPI, Port A as input, Port B as output, Port C as don’t care and it is operating in Mode 0 is given by:-           _____

                 

                  (A) 96                                                  (B) 97

                  (C) 98                                                  (D) 90

 

             g.   During DMA operation

 

                  (A) Accumulator is involved in data transfer                                                                       

                  (B) Accumulator is not involved in data transfer

                  (C) HL register pair is involved in data transfer                                                                  

                  (D) BC register pair is involved in data transfer

 

             h.  Synchronous characters are used in

                                                                                                                                                                       

(A)  8251                                                       (B) 8259

                  (C) 8255                                                       (D) 8253

 

             i.   The programmable interval timer 8253 has

 

                  (A) Two modes of operation                 (B) Five modes of operation

                  (C) Six modes of operation                   (D) Ten modes of operation

                                                                          

             j.   A microcontroller has  

 

                  (A) No memory and two ports inside    (B) Many ports and memory inside

                  (C) No ports and no memory inside      (D) One port and no memory inside

            

 

Answer any FIVE Questions out of EIGHT Questions.

Each question carries 16 marks.

 

 

  Q.2     a.   Explain the function of registers of 8085 and explain their individual significance.                  (8)

                  

             b.   Explain the consequences of executing the following instructions:

                   (i)   DAA                                             (ii)   NOP

                   (iii) ANI data                                       (iv)  PUSH PSW                                    (8)

 

  Q.3     a.   Explain the architecture of 8085 with a neat diagram.                                          (8)

            

             b.   Two memories and Two I/O ports are to be interfaced with 8085.

                   (i)   EPROM – 2KB

                   (ii)  RAM ------2KB

                   (iii) One keyboard (I/P) and one 7 segment display (O/P) device.  Give a chip select scheme with address map for the same.                                (8)

 

Q.4       a.   Write an assembly language program to exchange two arrays of length         100 bytes each.  Write appropriate comments.                        (8)

       

             b.   Write an ALP to multiply two eight bit numbers with repeated addition.               (8)

 

Q.5     a. List the hardware and software interrupts available in 8085.  How are they            triggered?            (8)

 

             b.   Give the structure of RIM and SIM instructions and explain their other uses also.                (8)

       

  Q.6     a.   The PPI 8255 is operated in Bidirectional data transfer mode with hand shake signals.  Explain the steps involved in the process.                        (8)

 

             b.   Give the block diagram of 8279 Keyboard/ display controller interface and explain each block.                                                                 (8)

 

  Q.7     a.   What is the need for a PIC?  Explain the internal architecture of a PIC.               (8)

       

             b.   What is DMA?  How do you use a programmable DMAC chip to achieve this?                 (8)

       

  Q.8     a.   Program the 8253 to generate a mode 0 type interrupt.  Explain this operation with waveforms.                                                                 (8)

 

             b.   Give the pin descriptions of 8251 with a neat diagram.                                        (8)

 

  Q.9     a.   Give the architecture of a microcontroller and explain how it is different from a microprocessor.                                                                 (8)

 

             b.   Write a program to transfer a block of 10 bytes from one part of the memory to another part of memory using a microcontroller.                        (8)