AU Solved Paper set - 2

AU Solved Paper

December-2011

Microprocessors & Microcontrollers

Semester-VI (EEE)

Time: Three Hours]

[Maximum Marks: 100

Answer ALL Questions

PART - A (10 × 2 = 20 Marks)

Q.1 Draw the schematic of latching low-order address bus in 8085 microprocessor. (Refer section 1.4.2)

Q.2 If the stack segment register contains 3000h and stack pointer register contains 8434h, what is the physical address of the top of the stack in 8086 microprocessor? (Refer section 14.4.3.4)

Q.3 Why do we need look-up table? (Refer section 3.3)

Q.4 How are the 8085 instructions classified according to the functional categories? (Refer section 2.2)

Q.5 Draw the 'Mode Word' format of 8251 USART. (Refer Fig. 11.5.1)

Q.6 State the use of ISR and PR registers in 8259 PIC. (Refer section 9.3)

Q.7 List the on-chip peripherals of 8051 microcontroller. (Refer section 14.3)

Q.8 What are the addressing modes of 8051 microcontroller? (Refer section 15.1)

Q.9 Why do we need opto-isolator circuit between microcontroller and the stepper motor? (Refer section 17.4)

Q.10 Mention the I/O instructions of 8051 microcontroller. (Refer section 15.3)

PART B (16 × 5 = 80 Marks)

Q.11 a) i) Explain in detail the 8085 interrupt structure. (Refer section 4.6)

[8]

ii) Draw the timing diagram for IN and OUT instruction of 8085 and explain. (Refer section 5.7) [8]

OR

b) i) Draw the internal block diagram of 8086 and explain the bus interface unit and execution unit. (Topic not included in new syllabus (course 2013)) [8]

ii) How address decoding is done in memory interface. (Refer section 6.4)

Q.12 a) i) Write a program to count from 0 to 9 with one second delay between each count. At the count of 9, the counter should reset itself to 0 and repeat the sequence continuously. Assume the clock frequency is 1 MHz.

(Refer section 3.2) [8]

ii) Write a program with a flowchart to multiply two 8-bit numbers.

(Refer section 2.5) [8]

OR

b) i) Compare the similarities and differences of CALL and RET instructions with PUSH and POP instructions. (Refer section 2.7) [8]

ii) Sixteen bytes are stored in memory locations at XX50h to XX5Fh. Transfer the entire block of data to new memory locations starting at XX70h. (Refer section 2.5) [8]

Q.13 a) i) Explain the operating modes of 8255 programmable peripheral interface. (Refer section 8.4) [8]

ii) Draw the logical block diagram of 8279 keyboard display controller and explain. (Refer section 12.5) [8]

OR

b) i) Draw the control word of 8253 timer/counter and explain the operating modes of 8253 timer/counter. (Refer sections 10.3 and 10.4) [8]

ii) Why do we need A/D converter and D/A converter? Draw the block diagram to interface 8085 microprocessor with A/D convertor and D/A convertor. (Refer sections 13.1, 13:3, 13.4 and 13.6)

Q.14 a) i) Explain the program memory and data memory structure of 8051 microcontroller. (Refer section 14.5.1) [8]

ii) Draw the pin diagram of 8051 microcontroller and explain its port structure. (Refer section 14.4) [8]

OR

b) i) Draw the TMOD register format and explain the different operating modes of timer in 8051 microcontroller. (Refer sections 16.3.1 and 16.4)

ii) Explain how serial communication is performed in 8051 microcontroller. (Refer section 16.6) [8]

Q.15 a) i) Explain with a program to rotate the stepper motor in both clockwise and anticlockwise direction using 8051 microcontroller. (Refer section 17.4) [8]

ii) How to interface a 7 segment display using 8051 microcontroller. (Refer section 17.2.2) [8]

OR

b) i) How 8051 is used in washing machine control? (Refer section 17.4) ii) How do you interface a 4 × 4 matrix keyboard using 8051 microcontroller? (Refer section 17.1.4) [8]